Journal of Epidemiology
Online ISSN : 1349-9092
Print ISSN : 0917-5040
Advance online publication
Showing 1-50 articles out of 63 articles from Advance online publication
  • Ryoma Michishita, Takuro Matsuda, Shotaro Kawakami, Satoshi Tanaka, Ak ...
    Article ID: JE20170304
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: This study investigated the relationship between long-term body weight gain after maturity and the incidence of chronic kidney disease (CKD).

    Methods: The participants were 303 men without a history of cardiovascular and cerebrovascular diseases, kidney dysfunction, or dialysis treatment. Their body weight gain after maturity was examined using a standardized self-administered questionnaire. The participants were divided into two groups based on the presence/absence of a body weight gain of ≥10 kg since 20 years of age.

    Results: After a 6-year follow-up, the cumulative incidence of CKD was significantly higher in participants with a body weight gain of ≥10 kg than in participants without body weight a body weight gain of ≥10 kg since 20 years of age (log-rank test: P = 0.041). After adjusting for the age, body mass index, estimated glomerular filtration rate levels, smoking and drinking habits, and the presence of hypertension, dyslipidemia, and hyperglycemia at baseline, the normal body weight participants with a body weight gain of ≥10 kg since 20 years of age was significantly related to the incidence of CKD (hazard ratio 2.47; 95% confidence of interval, 1.02–6.01, P = 0.045).

    Conclusions: These results suggest that long-term body weight gain after maturity in normal body weight participants may be associated with the incidence of CKD, independent of current body weight.

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  • Hiroshi Murayama, Mika Sugiyama, Hiroki Inagaki, Chiaki Ura, Fumiko Mi ...
    Article ID: JE20180002
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Despite increasing evidence of an association between childhood socioeconomic disadvantage and cognitive outcomes, such as dementia and cognitive decline, in Western countries, there are no studies on this association from non-Western societies. We investigated the relationship between childhood socioeconomic status (SES) and subjective symptoms of dementia among community-dwelling older Japanese people and examined age and sex variations in this association.

    Methods: Data were derived from a cross-sectional survey for all community-dwelling individuals aged 65 years and over in Adachi, Tokyo (n = 132,005). We assessed subjective dementia symptoms using a self-administered dementia checklist, which was validated by comparison with the Clinical Dementia Rating scale.

    Results: Data from 75,358 questionnaires were analyzed. After adjusting for potential covariates, lower childhood SES was associated with greater likelihood of subjective dementia symptoms. We found a significant interaction between childhood SES and age on subjective dementia symptoms but no interaction between childhood SES and sex. Age-stratified analysis indicated that the association between lower childhood SES and subjective dementia symptoms was stronger in the ≥75 years subgroup than in the 65–74 years subgroup, indicating an effect modification of age on this association.

    Conclusions: Our findings suggested that low SES in childhood might have a long-term influence on dementia symptoms in late life and that this influence varied by age. This differential association might be explained by the social and historical context in Japan (ie, World War II, postwar chaos, and high economic growth) that has shaped participants’ early experiences.

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  • Chisato Nagata, Keiko Wada, Yukari Sahashi, Takashi Tamura, Kie Konish ...
    Article ID: JE20180005
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The early life environment is now recognized as a key factor contributing to susceptibility to certain diseases in later life.

    Methods: We initiated a cohort study among school children in 2011 to primarily investigate the associations between lifestyle and environmental factors and some surrogate markers of chronic diseases, such as cardiometabolic risk factors (ie, obesity, high blood pressure, high blood glucose, insulin, or lipids) and cancer risk factors (ie, height and age at menarche). A baseline questionnaire asked for information, including demographic variables, medical history and use of medication, dietary habits, physical activity, sleep habits, and behavioral and emotional problems of children. Follow-up surveys are planned for the fourth grade of elementary school and the first grade of junior high school. At these follow-up surveys, fasting blood samples will be obtained to measure cardiometabolic markers. We also checked the validity of a food frequency questionnaire, which was originally created for 6-year-olds but was modified for use in older children.

    Results: A total of 3,141 first-year students at elementary schools in Hekinan City, Aichi Prefecture, participated in the study. The response rate was 87.4%. The means of age and body mass index were 6.99 (standard deviation, 0.28) years and 15.3 (standard deviation, 1.7) kg/m2, respectively, in the 3,067 Japanese children (1,639 boys and 1,428 girls).

    Conclusions: This cohort will reveal determinants of cardiometabolic risk factors and cancer risk factors during childhood.

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  • Aya Fujiwara, Kentaro Murakami, Keiko Asakura, Ken Uechi, Minami Sugim ...
    Article ID: JE20180036
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The lack of comprehensive food composition databases for sugar contents in Japanese foods has led to the lack of nutritional epidemiologic studies on sugar intake in Japanese population. This cross-sectional study aimed to investigate the association of free sugar intake estimated using a newly-developed food composition database with the characteristics and lifestyles of Japanese children aged 3-6 years.

    Methods: The food composition database contained information on sugars in 2222 commonly consumed Japanese foods. Using this database, we estimated the sugar (total, added, and free sugars) intakes derived from a 3-day weighed dietary record of 166 boys and 166 girls aged 3-6 years living in 24 prefectures in Japan.

    Results: The mean free sugar intake was 26.8 g/d (standard deviation (SD), 12.3 g/d), while the mean value for energy intake was 7.8% (SD, 3.2%). The prevalence of excessive free sugar intake (≥10% of energy intake) was 21.7%. Among the characteristics and lifestyles examined, screen time was most strongly associated with the prevalence of excessive free sugar intake: multivariate adjusted odds ratios (95% confidence intervals) for screen time <0.5, ≥0.5 to <1, and ≥1 h/d were 1.0 (reference), 3.81 (1.04, 13.98), and 4.36 (1.16, 16.35), respectively. Additionally, younger age, shorter sleep, and mothers with office work and service and sales jobs (compared with those with professional and managerial jobs) were significantly associated with a higher prevalence of excessive free sugar intake.

    Conclusions: This study showed the sugar intake of Japanese children aged 3-6 years is positively associated with screen time.

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  • Robab Breyer-Kohansal, Sylvia Hartl, Otto Chris Burghuber, Matthias Ur ...
    Article ID: JE20180039
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The Lung, hEart, sociAl, boDy (LEAD) Study (ClinicalTrials.gov; NCT01727518; http://clinicaltrials.gov) is a longitudinal, observational, population-based Austrian cohort that aims to investigate the relationship between genetic, environmental, social, developmental and ageing factors influencing respiratory health and comorbidities through life. The general working hypothesis of LEAD is the interaction of these genetic, environmental and socioeconomic factors influences lung development and ageing, the risk of occurrence of several non-communicable diseases (respiratory, cardiovascular, metabolic and neurologic), as well as their phenotypic (ie, clinical) presentation.

    Methods: LEAD invited from 2011–2016 a random sample (stratified by age, gender, residential area) of Vienna inhabitants (urban cohort) and all the inhabitants of six villages from Lower Austria (rural cohort). Participants will be followed-up every four years. A number of investigations and measurements were obtained in each of the four domains of the study (Lung, hEart, sociAl, boDy) including data to screen for lung, cardiovascular and metabolic diseases, osteoporosis, and cognitive function. Blood and urine samples are stored in a biobank for future investigations.

    Results: A total of 11.423 males (47.6%) and females (52.4%), aged 6–80 years have been included in the cohort. Compared to governmental statistics, the external validity of LEAD with respect to age, gender, citizenship, and smoking status was high.

    Conclusions: In conclusion, the LEAD cohort has been established following high quality standards; it is representative of the Austrian population and offers a platform to understand lung development and ageing as a key mechanism of human health both in early and late adulthood.

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  • Joo-Young Lee, Eun-Song Lee, Gyung-Min Kim, Hoi-In Jung, Jeong-Woo Lee ...
    Article ID: JE20180052
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Some previous studies reported hearing ability can be reduced by impaired masticatory ability, but there has been little evidence reported of an association between hearing loss and unilateral mastication. Therefore, this study aimed to investigate the relationship between unilateral mastication (UM), estimated from individual functional tooth units (FTUs), and hearing loss in a representative sample of Korean adults.

    Methods: The analyzed data were obtained from 1,773 adults aged 40–89 years who participated in Korean national survey. Hearing loss was defined as a pure-tone average of >25 dB at frequencies of 0.5, 1, 2, and 4 kHz in either ear. In each subject, UM was calculated as the difference in the sums of the FTU scores, which is an index of posterior tooth occlusion, on the two sides of the oral cavity. The scores were used to classify the UM into low, moderate, and high. The adjusted odds ratios (aORs) and their 95% confidence intervals (CIs) were calculated in multivariable logistic regression analyses.

    Results: When controlling for sociodemographic factors, the aOR for hearing loss was 3.12 (95% CI, 1.21–8.03) for high UM relative to low UM. This association remained in a fully-adjusted model containing factors related to noise exposure (aOR 2.88; 95% CI, 1.12–7.46).

    Conclusion: Adults with high UM as measured using FTUs showed a higher occurrence of hearing loss than those with low UM.

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  • Kaoru Araki, Megumi Hara, Chisato Shimanoe, Yuichiro Nishida, Muneaki ...
    Article ID: JE20180054
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Selection of test-negative controls takes less time and costs less than traditional control selection for evaluating vaccine effectiveness (VE). Here, rotavirus VE was evaluated using hospital controls and compared with test-negative controls to determine whether using the latter can substitute for the former.

    Methods: We recorded gastroenteritis in children from 2 months to 2 years of age at six medical facilities in Saga City between January 4th and May 31st, 2014. Stools from all identified acute gastroenteritis patients were tested for rotavirus using immunochromatography. Rotavirus gastroenteritis (RVGE) cases had test-positive stool, whereas test-negative controls had gastroenteritis but no rotavirus infection; hospital controls were outpatients visiting the same facility for indications other than gastroenteritis. Vaccination status was verified by inspecting maternal and child health records, and demographic data were obtained from a questionnaire completed by the patients’ guardians or from the medical records. Unconditional logistic regression analysis was used to adjust for possible confounding factors.

    Results: Sixty-four RVGE cases, 260 test-negative controls, and 589 hospital controls were enrolled. The characteristics of the two control groups, including RV vaccination history, were similar. The RVGE cases were more likely to have used daycare services than children from either of the two control groups. The VE against RVGE estimated using hospital controls was 86.6% (95% confidence interval [CI], 55.9–96.0%), very similar to the VE using test-negative controls (84.9% [95% CI, 49.6–95.5%]).

    Conclusions: The estimated VE using test-negative controls and hospital controls is similar. Therefore, test-negative controls are considered appropriate for establishing VE.

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  • Taro Kusama, Jun Aida, Kemmyo Sugiyama, Yusuke Matsuyama, Shihoko Koya ...
    Article ID: JE20180080
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Although majority of survivors of the huge earthquake and tsunami evacuated to two types of temporary housings, prefabricated housing and rented housing, health effects of these different environments were unclear. We examined whether prevalent social participation in prefabricated housing brought larger health benefits than in rented housing using the largest health survey data of the disaster survivors.

    Methods: This cross-sectional study used a 2012 survey by the Miyagi Prefectural Government in which almost all of evacuees were targeted (response rate = 61.6%). Self-rated health (SRH) and psychological distress measured by K6 score were the dependent variables, and social participation was the independent variable. Odds ratios of the social participation on health variables were estimated by logistic regression models. To assess the contribution of social participation, the population attributable fraction (PAF) was estimated.

    Results: The participants lived in prefabricated and rented housing numbered 19,077 and 28,270, respectively. Participants in prefabricated housing had poorer SRH and K6 than those in rented housing. Social participation of prefabricated and rented housing were 38.2% and 15.4%, respectively. The absence of social participation was significantly associated with poor SRH and K6 among participants in both housing types. The PAFs of social participation with good SRH were 39.5% in prefabricated housing and 14.4% in rented housing. For K6, the PAFs were 47.1% and 19.5% in prefabricated and rented housing, respectively.

    Conclusion: Compared to the residents in rented housing, residents in prefabricated housing had more frequent opportunities for social participation, which was associated with larger health benefits.

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  • Paul H. Lee
    Article ID: JE20180095
    Published: 2018
    [Advance publication] Released: October 20, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: In research using accelerometers to measure physical activity, the number of accelerometers that can be utilized in a study and the study duration are both constrained. It means that increasing the number of accelerometer wearing days for all subjects leads to a decrease in the total number of participants the study can recruit. We used simulations to find the optimal number of wearing days / number of participant combination given a fixed number of accelerometer days.

    Methods: Two scenarios were studied here, including estimation of population physical activity level and the association between physical activity level and a health outcome. Another similar simulation was conducted by bootstrapping the National Health and Nutrition Examination Survey (NHANES) 2003-2006 accelerometer data (n=4,069).

    Results: The simulation results of the first scenario showed that the error was minimized when the wearing day was one to two. Simulation results of the second scenario showed that the optimal number of wearing days increased with the total number of accelerometer days and decreased with intra-class correlation (ICC).

    Conclusion: We developed a tool for researchers to determine the optimal combination of number of the accelerometer wearing days and the total number of participants, and showed that one to two accelerometer wearing day is optimal for estimation of population physical activity level.

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  • Kumiko Ito, Tomoyuki Hanaoka, Naomi Tamura, Seiko Sasaki, Chihiro Miya ...
    Article ID: JE20170185
    Published: 2018
    [Advance publication] Released: October 13, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Low red blood cell folate concentrations during early pregnancy might cause neural tube defects. However, the association between folate concentrations and birth defects of other neural crest cell-derived organs remains unknown. We investigated the associations between birth defects and first-trimester serum folate concentrations in a birth-cohort study in Japan.

    Methods: In total, 14,896 women who were prior to 13 weeks of gestation were enrolled from 2003 through 2012. Birth defect information was obtained from medical records and questionnaires. The association between folate levels in the first trimester and birth defects categorized as ICD-10 cord defects and neural crest cell-derived organ defects was examined. The crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) per log-transformed folate concentration were calculated using logistic regression.

    Results: Blood samples were obtained at a mean of 10.8 weeks of gestation. Median serum folate level was 16.5 (interquartile range, 13.4–21.5) nmol/L, and the deficiency level (less than 6.8 nmol/L) was 0.7%. There were 358 infants with birth defects. The adjusted odds ratio for any birth defect, ventricular septal defects, and cleft lip was 0.99 (95% CI, 0.74–1.32), 0.63 (95% CI, 0.30–1.33), and 4.10 (95% CI, 0.96–17.58), respectively. There were no significant associations between first-trimester maternal serum folate and the risk of birth defects.

    Conclusions: We were unable to demonstrate a relationship between maternal serum folate in the first trimester and birth defects. Potential confounding factors may have influenced our results.

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  • Kimiko Tomioka, Norio Kurumatani, Keigo Saeki
    Article ID: JE20180108
    Published: 2018
    [Advance publication] Released: October 13, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Participation in leisure activities (LA) is essential for successful aging. Our aim was to investigate the cross-sectional association of types of LA with self-rated health (SRH) by gender and work status.

    Methods: The target population was all residents aged ≥65 years in a municipality (n = 16,010, response rate of 62.5%). We analyzed 4,044 men and 4,617 women without disabilities. LA were categorized into 14 types. SRH was assessed through the SF-8. Excellent or very good SRH was defined as positive SRH. Covariates included age, marital status, education, subjective economic status, body mass index, chronic diseases, alcohol, smoking, walking time, depression and cognitive functioning. Multiple logistic regressions were used to calculate the odds ratio (OR) and 95% confidence interval (CI) for positive SRH, with non-participation as the reference.

    Results: After adjustment for covariates and mutual adjustment for other LA, participation in the following types of LA was positively associated with positive SRH: regarding sports activities, working men (OR = 1.46, 95% CI = 1.07-2.00), non-working men (1.33, 1.04-1.69), and non-working women (1.74, 1.41-2.15); regarding cooking, non-working men (1.65, 1.18-2.33) and non-working women (1.28, 1.03-1.60); regarding musical activities, working men (1.44, 1.01-2.05) and non-working women (1.59, 1.29-1.95); and regarding technology usage, only working men (1.41, 1.01-1.96). In contrast, TV watching was negatively associated with positive SRH among non-working women (0.69, 0.56-0.85).

    Conclusions: Our results suggest that encouraging older adults to participate in types of LA appropriate to their gender and work status might be a key to positive SRH.

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  • Takahiro Tabuchi, Tomohiro Shinozaki, Naoki Kunugita, Masakazu Nakamur ...
    Article ID: JE20180116
    Published: 2018
    [Advance publication] Released: October 13, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Japan became the first country where heat-not-burn tobacco products were sold. Therefore, there was no information for actual status of heat-not-burn tobacco products.

    The objectives of the study profile are to inform that data can be freely available to external researchers, and to create collaborative research projects in the future.

    Methods: The Japan “Society and New Tobacco” Internet Survey (JASTIS) is a longitudinal internet cohort study which investigates perception, attitude and use of heat-not-burn tobacco, electronic cigarettes (e-cigarettes) and conventional tobacco products in Japan. The survey also includes demographic, health-related and socioeconomic factors. Participants were randomly selected and invited from internet panellists. The baseline survey was closed when the target number of respondents who had answered the questionnaire was met.

    Results: The study includes three cohorts (1-3) from the 2015 baseline survey and a cohort (4) from the 2017 baseline survey: cohort 1&4 were recruited based on sex and age: men and women aged 15-69 years (n=8240 for cohort 1 and n=5897 for cohort 4); cohort 2&3 were made by use status-based recruiting: e-cigarette and/or heat-not-burn tobacco ever users (n=2188; cohort 2) and combustible cigarette smokers without e-cigarette/heat-not-burn tobacco experience (n=724; cohort 3). The completion rates were 8.5 to 9.9%. All subjects were followed and assessed annually. Response rates for the follow-up survey were 65.5% in 2016, 55.3% in 2017 and 50.9% in 2018. Because Internet-based responders differ from the representative sample in Japan, we conducted the adjustment to account for “being an internet survey respondent” and reported about the products use in Japan. Recent study reported that prevalence of IQOS current-use among Japanese adults had rapidly increased to 3.6% in 2017.

    Conclusion: The JASTIS study provides the first estimates for heat-not-burn tobacco use in the world and e-cigarette use in Japan. For information on collaboration, please contact the corresponding author.

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  • Hyeong Taek Woo, Jin Ah Sim, Jonghoon Mo, Young Ho Yun, Aesun Shin
    Article ID: JE20170331
    Published: 2018
    [Advance publication] Released: October 06, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Objective: Colorectal cancer (CRC) is the 4th common site for cancer death in Republic of Korea. The aim of this study was to describe the trends of colorectal cancer mortality by regions.

    Methods: CRC mortality trends in Republic of Korea by region were described using a Joinpoint regression model in both sexes. The annual percent changes (APC) were calculated for each segment. Visualization of the changes in mortality rate of colorectal cancer death rates by 16 geographic areas in both sexes between 2000-2004 and 2009-2013 were also conducted.

    Results: CRC mortality rates of men showed decreasing trend after increase in Daegu, Gyeongsangnam-do and Chungcheongbuk-do between 2000 and 2013 based on the joinpoint model. While, Gwangju, Jeollabuk-do, Jeollanam-do, Gyeongsangbuk-do showed increase in CRC mortality during the same period. For women, CRC mortality of Seoul, Incheon, Daejeon and Gyeongsangnam-do started to decrease in 2005, 2003, 2007 and 2006 respectively. The mortality rate for CRC in the eastern regions, which had relatively low rates of CRC among men in 2000 to 2004, reached a level similar to that in the northwestern regions of 2009 to 2013, while the highest CRC mortality rates in women was observed in Chungcheongbuk-do.

    Conclusions: Reduction in CRC mortality varied across 16 metropolitan cities and provinces in men, and the visualization pattern showed that the east side of South Korea had the least progress in mortality reduction.

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  • Kimiko Tomioka, Norio Kurumatani, Keigo Saeki
    Article ID: JE20180113
    Published: 2018
    [Advance publication] Released: October 06, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: To examine the relationship of working history from early adulthood through old age with instrumental activities of daily living (IADL).

    Methods: Analyzed participants were 5,857 community-dwelling older Japanese people aged ≥65. Using the Tokyo Metropolitan Institute of Gerontology Index of Competence, IADL decline was defined as individuals who had no IADL dependence at baseline, but were deemed as dependent in IADL at follow-up. Work history was based on working status at baseline, total working years, and information concerning the longest held job, including occupation, employment pattern, and workplace size (number of employees). We conducted multiple logistic regression analyses and estimated the odds ratio (OR) for IADL decline with 95% confidence interval (CI) by gender.

    Results: At the 33-month follow-up, 428 men (16.6%) and 275 women (8.4%) developed IADL decline. After covariate adjustments, men with unstable employment reported significantly increased IADL decline (OR=1.52, 95% CI=1.19-1.95) compared to men with stable employment, and men who worked in small workplaces with 1-49 employees had an increased risk for IADL decline (1.53, 1.21-1.93) compared to men in large-sized workplaces with ≥50 employees. After mutual adjustment for all working history items, only the association between small workplaces and IADL decline remained significant in men (1.37, 1.03-1.84). Among women, none of working history items was associated with IADL decline.

    Conclusion: Our results suggest that not only promoting older people’s workforce participation, but also providing workers employed at small workplaces with sufficient occupational health services, may be effective in helping retain male IADL in later life.

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  • Toshiharu Ninomiya
    Article ID: JE20180150
    Published: 2018
    [Advance publication] Released: October 06, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    The Hisayama Study is a population-based prospective cohort study designed to evaluate the risk factors for lifestyle-related diseases, such as stroke, coronary heart disease, hypertension, diabetes, and dementia, in a general Japanese population. The prospective follow-up surveys have been conducted in subjects aged 40 or older since 1961. Notable characteristics of this study include its high participation rate (70–80% of all residents aged 40 or older), high follow-up rate (99% or over), and high autopsy rate (approximately 75% of deceased cases). The Hisayama Study has provided valuable evidence of secular change in the prevalence and incidence of several lifestyle-related disease and their risk factors. The study has thereby contributed to elucidation of the preventive strategies for lifestyle-related disease. Research efforts in this cohort are ongoing and will provide additional data for the improvement of human health and longevity.

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  • Hiroyuki Kikuchi, Keisuke Kuwahara, Kosuke Kiyohara, Ester Villalonga- ...
    Article ID: JE20180184
    Published: 2018
    [Advance publication] Released: October 06, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION
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  • Yang Yu, Wendy Cozen, Amie E. Hwang, Myles G. Cockburn, John Zadnick, ...
    Article ID: JE20170159
    Published: 2018
    [Advance publication] Released: September 29, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Inherited factors and maternal behaviors are thought to play an important role in the etiology of several congenital malformations. Twin studies can offer additional evidence regarding the contribution of genetic and lifestyle factors to common birth anomalies, but few large-scale studies have been reported.

    Methods: We included data from twins (20,803 pairs) from the population-based California Twin Program. We compared concordance in monozygotic (MZ) to dizygotic (DZ) twins for the following birth anomalies: clubfoot, oral cleft, spina bifida, muscular dystrophy, deafness, cerebral palsy, strabismus, and congenital heart defects. Each birth anomaly was also examined for the associations with birth characteristics (birthweight and birth order) and parental exposures (age, smoking, and parental education).

    Results: The overall prevalence of any selected birth anomaly in California twins was 38 per 1,000 persons, with a slightly decreasing trend from 1957–1982. For pairwise concordance in 6,752 MZ and 7,326 like-sex DZ twin pairs, high MZ:DZ concordance ratios were observed for clubfoot (CR 5.91; P = 0.043) and strabismus (CR 2.52; P = 0.001). Among the total 20,803 pairs, parental smoking was significantly associated with risk of spina bifida (OR 3.48; 95% CI, 1.48–8.18) and strabismus (OR 1.61; 95% CI, 1.28–2.03). A significant quadratic trend of increasing risk for clubfoot, spina bifida, and strabismus was found when examining whether father smoked, mother smoked, or both parents smoked relative to non-smoking parents (P = 0.029, 0.026, and 0.0005, respectively).

    Conclusions: Our results provide evidence for a multifactorial etiology underlying selected birth anomalies. Further research is needed to understand the biological mechanisms.

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  • Shogo Kikuchi, Mototsugu Kato, Katsuhiro Mabe, Takashi Kawai, Takahisa ...
    Article ID: JE20170094
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Practical criteria for the use of serum pepsinogen (PG) values in diagnosing Helicobacter pylori infection have not yet been determined.

    Methods: The results of gastric endoscopies, H. pylori infection tests, and PG values were retrospectively reviewed. Subjects were assigned to groups, including never-infected (with neither infection nor gastric mucosal atrophy), infected (with atrophy or findings indicating infection in endoscopy and positive infection tests except for antibody tests), and ex-infected (with gastric mucosal atrophy and negative infection tests, except for antibody tests). The optimal criteria with combined use of the PG II concentrations and the PG I/PG II ratio were investigated separately for PG measurements obtained with the chemiluminescent magnetic particle immunoassay (CLIA) and latex agglutination (LA) methods, such that the specificity was greater than 70% and the sensitivity was no less than 95% among the never-infected and infected subjects. Similar analyses were performed by combining the data from ex-infected and infected subjects.

    Results: For the CLIA (LA) method, the optimal criterion among 349 (397) never-infected and 748 (863) infected subjects was a PG II value of at least 10 (12) ng/mL or a PG I/PG II ratio no more than 5.0 (4.0), which produced 96.3% (95.1%) sensitivity and 82.8% (72.8%) specificity. When 172 (236) ex-infected subjects were included, the optimal criterion was the same, and the sensitivity was 89.1% (86.9%).

    Conclusions: The above criteria may be practical for clinical use, and PG tests using these criteria might prevent unnecessary endoscopic examinations for never-infected subjects.

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  • Hitomi Fujita, Akihiro Hosono, Kiyoshi Shibata, Shoko Tsujimura, Kyoko ...
    Article ID: JE20170180
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: It is known that physical activity affects glucose metabolism. However, there have been no reports on the influence of physical activity earlier in life on subsequent glucose metabolism. Therefore, we analyzed the influence of physical activity in earlier decades of life on insulin resistance in middle aged and older residents in Japan.

    Methods: The subjects were 6,883 residents of Okazaki City between the ages of 40 and 79 years who underwent physical examinations at the Okazaki City Medical Association Public Health Center from April 2007 through August 2011. They gave informed consent for participation in the study. Data on individual characteristics were collected via a questionnaire and from the health examination records. Fasting blood glucose and insulin levels were used to calculate the homeostatic model assessment of insulin resistance (HOMA-IR). HOMA-IR >1.6 was considered to indicate insulin resistance for the purpose of logistic regression models.

    Results: The study sample included 3,683 men and 3,200 women for whom complete information was available. For those who exercised regularly throughout their teens to their 30s–40s, the odds ratio for having insulin resistance was 0.75 (95% confidence interval [CI], 0.58–0.96) for men and 0.76 (95% CI, 0.58–0.99) for women after adjusting for other variables, including age, body mass index, and present physical activity. A linear trend was also observed in both men and women.

    Conclusions: Subjects who have exercised regularly in the early decades of life are less likely to have insulin resistance later in life.

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  • Shigekazu Ukawa, Wenjing Zhao, Hiroshi Yatsuya, Kazumasa Yamagishi, Na ...
    Article ID: JE20170341
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The association between daily walking and pneumonia mortality, stratified by the presence of disease conditions, such as myocardial infarction (MI) or stroke, was investigated.

    Methods: The study participants were 22,280 Japanese individuals (9,067 men and 13,213 women) aged 65–79 years. Inverse propensity weighted competing risk model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for pneumonia mortality.

    Results: After a median of 11.9 years of follow-up, 1,203 participants died of pneumonia. Participants who did not have a history of MI or stroke and who walked for 1 hour/day or more were less likely to die from pneumonia (HR 0.90; 95% CI, 0.82–0.98) than those walked for 0.5 hours/day. A similar inverse association of pneumonia and walking (0.5 hours/day) was observed among participants with a history of MI (HR 0.66; 95% CI, 0.48–0.90). Among the participants with a history of stroke, those who walked for 0.6–0.9 hours/day were less likely to die because of pneumonia (HR 0.65; 95% CI, 0.43–0.98).

    Conclusions: Regular walking for ≥1 hour/day may reduce the risk of pneumonia mortality in elderly individuals with or without cardiovascular disease history.

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  • Hidetoshi Mezawa, Ai Tomotaki, Kiwako Yamamoto-Hanada, Kazue Ishitsuka ...
    Article ID: JE20180014
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The aims of the present report were to estimate the prevalence of congenital anomalies (CAs) among infants in Japan using data from the Japan Environment and Children’s Study (JECS) and to evaluate the validity of CA classification within JECS.

    Methods: Data on CAs were collected at delivery and at age 1 month from the medical records of 101,825 infants at 15 regional centers. The analyses focused on 61 CAs, selected on the basis of reported associations with environmental exposure. Prevalence per 10,000 pregnancies (including miscarriages, stillbirths, and live births) was stratified according to four reporting patterns (at delivery, at age 1 month, at either, and at both). To evaluate the accuracy of observed CA prevalence, the medical records of 179 cases from a single JECS regional center underwent independent, retrospective re-evaluation.

    Results: The prevalence of major CAs in four reporting patterns (at delivery, at age 1 month, at either, and at both) was 2.4, 2.6, 3.5, and 1.4 for myelomeningocele/spina bifida; 4.3, 4.2, 5.3, and 3.2 for cleft palate; 18.1, 17.4, 19.5, and 15.1 for cleft lip with or without cleft palate; 73.4, 100.3, 120.8, and 52.8 for congenital heart disease; and 10.5, 14.1, 15.0, and 9.6 for Down’s syndrome, respectively. In the subsample re-evaluation, CA diagnoses were confirmed for 92.7%, 93.3%, 90.5%, and 97.8% of cases in the four reporting patterns (at delivery, at age 1 month, at either, and at both), respectively.

    Conclusions: The present report generated reliable data concerning the prevalence of major CAs in JECS.

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  • Shota Hamada, Hideto Takahashi, Nobuo Sakata, Boyoung Jeon, Takahiro M ...
    Article ID: JE20180055
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: This study aimed to determine whether there are disparities in healthcare services utilization according to household income among people aged 75 years or older in Japan.

    Methods: We used data on medical and long-term care (LTC) insurance claims and on LTC insurance premiums and needs levels for people aged 75 years or older in a suburban city. Data on people receiving public welfare were not available. Participants were categorized according to household income level using LTC insurance premiums data. The associations of low income with physician visit frequency, length of hospital stay (LOS), and medical and LTC expenditures were evaluated and adjusted for the five-year age group and LTC needs level.

    Results: The study analyzed 12,852 men and 18,020 women, among which 13.3% and 41.5% were respectively categorized as low income. Participants with low income for both genders were more likely to be functionally dependent. In the adjusted analyses, lower income was associated with fewer physician visits (incidence rate ratio: 0.90 (95% confidence interval 0.87-0.92) for men and 0.97 (0.95-0.99) for women), longer LOS (1.98 (1.54-2.56) and 1.42 (1.20-1.67)), and higher total expenditures (1.09 (1.01-1.18) and 1.09 (1.05-1.14)).

    Conclusions: This study suggests older people with lower income had fewer consultations with physicians but an increased use of inpatient services. The income categorization used in this study may be an appropriate proxy of socioeconomic status.

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  • Yasuyuki Okumura, Nobuo Sakata, Hisateru Tachimori, Tadashi Takeshima
    Article ID: JE20180066
    Published: 2018
    [Advance publication] Released: September 22, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Understanding the area-specific resource use of inpatient psychiatric care is essential for the efficient use of the public assistance system. This study aimed to assess the geographical variation in psychiatric admissions and to identify the prefecture-level determinants of psychiatric admissions among recipients of public assistance in Japan.

    Methods: We identified all recipients of public assistance who were hospitalized in a psychiatric ward in May 2014, 2015, or 2016 using the Fact-finding Survey on Medical Assistance. The age- and sex-standardized number of psychiatric admissions was calculated for each of the 47 prefectures, using direct and indirect standardization methods.

    Results: A total of 46,559 psychiatric inpatients were identified in May 2016. The number of psychiatric admissions per 100,000 population was 36.6. We found a 7.1-fold difference between the prefectures with the highest (Nagasaki) and lowest (Nagano) numbers of admissions. The method of decomposing explained variance in the multiple regression model showed that the number of psychiatric beds per 100,000 population and the number of recipients of public assistance per 1,000 population were the most important determinants of the number of psychiatric admissions (R2 = 28% and R2 = 23%, respectively). The sensitivity analyses, using medical cost as the outcome and data from different survey years and subgroups, showed similar findings.

    Conclusions: We identified a large geographical variation in the number and total medical cost of psychiatric admissions among recipients of public assistance. Our findings should encourage policy makers to assess the rationale for this variation and consider strategies for reducing it.

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  • Mai Utada, Shuji Yonehara, Kotaro Ozasa
    Article ID: JE20180037
    Published: 2018
    [Advance publication] Released: September 15, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Histological classification of lung cancer is essential for investigations of carcinogenesis and treatment selection. We examined the temporal changes of lung cancer histological subtypes.

    Methods: Lung cancer cases diagnosed in the Life Span Study cohort between 1958 and 1999 were collected from tumor registries (TR), mainly consisting of population-based cancer registries. A total of 1,025 cases were histologically reviewed according to the World Health Organization 2004 Classification by a panel of pathologists (PP). Sensitivity and specificity of diagnoses in TR were calculated, assuming that the diagnosis by PP was the gold standard.

    Results: Sensitivity and specificity were 0.91 and 0.92 for adenocarcinoma (AD), respectively, and 0.92 and 0.94, respectively, for squamous cell carcinoma (SQ). They were similar for AD and SQ throughout the observation period. For small cell carcinoma (SM), sensitivity was low until about 1980 (0.47 in 1958–1969, and 0.61 in 1970–1979) and then became higher thereafter (0.98 in 1980–1989, and 0.95 in 1990–1999), whereas specificity was high during the whole period (range 0.99 to 1.00). Among 45 cases that were not reported as SM in TR but diagnosed as SM by PP, 16 cases were recorded as undifferentiated carcinoma in TR.

    Conclusion: Diagnosis of AD and SQ of lung cancer were generally consistent between TR records and PP review, but SMs tended to be coded as other histological types until the 1970s.

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  • Yasuyuki Okumura, Naoya Sugiyama, Toshie Noda, Hisateru Tachimori
    Article ID: JE20180096
    Published: 2018
    [Advance publication] Released: September 15, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: A better understanding of resource use of new psychiatric admissions is important for healthcare providers and policymakers to improve psychiatric care. This study aims to describe the pattern of new psychiatric admissions and length of stay in Japan.

    Methods: A retrospective cohort study was conducted using data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB). All patients newly admitted to psychiatric wards from April 2014 through March 2016 were included and followed up until discharge to the community.

    Results: Our sample included 605,982 admissions from 1,621 hospitals over 2 years. The average monthly number of admissions was 25,024 in fiscal year 2014 and 25,475 in fiscal year 2015. There was a seasonal trend in the number of admissions, with a peak in summer (in July). The discharge rates within 90 days and 360 days were 64.1% and 85.7%, respectively, and varied by type of hospital fee and by hospital. For example, the range of hospital-level discharge rate within 90 days in psychiatric emergency units was 46.0–75.3% in the 1st (lowest) quintile, while it was 83.6–96.0% in the 5th (highest) quintile. The prefecture-level indicators in the NDB and the 630 survey had correlations of >0.70.

    Conclusions: Our study provides fundamental information on resource use of new psychiatric admissions in Japan. Although using the NDB has substantial benefits in monitoring resource use, the results should be interpreted with some caution owing to methodological issues inherent in the database.

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  • Minoru Takakura, Masaya Miyagi, Masaru Ueji, Minoru Kobayashi, Atsushi ...
    Article ID: JE20180125
    Published: 2018
    [Advance publication] Released: September 15, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: It is unclear that either neighborhood collective efficacy or school collective efficacy can be associated with adolescent alcohol use. This study aimed to examine the relative contributions of collective efficacy both in school and in the neighborhood contexts to alcohol use among Japanese adolescents.

    Methods: A cross-sectional study was conducted in public high schools across Okinawa and Ibaraki Prefectures in Japan in 2016. The study participants consisted of 3,291 students in grades 10 through 12 cross-nested in 51 schools and 107 neighborhoods. Alcohol use was measured by current alcohol drinking, that is self-reported drinking on at least one day in the past 30 days. Collective efficacy was measured by scales of social cohesion and informal social control in school and the neighborhood. Contextual-level collective efficacy was measured by aggregated school-level and neighborhood-level individual responses, respectively. We used non-hierarchical multilevel models to fit the cross-nested data.

    Results: Significant variation in alcohol use was shown between schools, but not between neighborhoods. After adjusting for covariates, school collective efficacy at individual- and contextual-levels were protectively associated with alcohol drinking (Odds Ratio [OR] for the increase of one standard deviation from the mean 0.72, 95% Confidence Interval [CI], 0.63–0.82; OR 0.61, 95% CI, 0.49–0.75), whereas neighborhood collective efficacy at individual- and contextual-levels were not associated with alcohol consumption.

    Conclusion: The school-level associations with adolescent alcohol use may have the greater impact than the neighborhood-level associations. Adolescent drinking prevention efforts should include enhancing school collective efficacy.

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  • Takashi Yorifuji
    Article ID: JE20180126
    Published: 2018
    [Advance publication] Released: September 15, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION
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  • Yi-Lung Chen, Shang-Chi Wu, Yen-Tyng Chen, Po-Chang Hsiao, Ya-Hui Yu, ...
    Article ID: JE20170300
    Published: 2018
    [Advance publication] Released: September 01, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The different profiles of e-cigarette users in different age groups have seldom been investigated, particularly in populations facing a high prevalence of cigarette smoking. This study aims to examine the prevalence and correlates of e-cigarette use separately for adolescents and adults in nationally representative samples in Taiwan.

    Methods: Among 17,837 participants in the 2014 National Survey of Substance Use in Taiwan, 4445 were aged 12 to 17 years and 13,392 were aged 18 to 64 years. Individuals’ lifetime tobacco use was divided into four groups: non-use, exclusive e-cigarette use, exclusive cigarette use, and dual use. Questions on sociodemographic features, use and problematic use of tobacco, alcohol, and other drugs, and psychosocial distress, among others, were administered using a computer-assisted self-interview on tablet computers.

    Results: Among lifetime users of e-cigarette (2.2% for adults and 0.8% for adolescents), 4.5% for adults and 36.6% for adolescents were exclusive e-cigarette users. From use of exclusive e-cigarettes to use of exclusive cigarettes to dual use, those usage groups were related to an increasing trend of adjusted odds ratios for use of other psychoactive substances, particularly problematic use of alcohol or drugs, and with more depressive symptoms. Two correlates were specific to e-cigarette use: alcohol use had stronger relationships with e-cigarette use among adolescents, and younger adults (18–34) were more likely to try e-cigarettes compared to older adults.

    Conclusions: These results provide essential information regarding e-cigarette use in the general population, and future prevention strategies should account for its specific correlates in young people.

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  • Jaesung Choi, Ji-Yeob Choi, Aesun Shin, Sang-Ah Lee, Kyoung-Mu Lee, Ju ...
    Article ID: JE20170296
    Published: 2018
    [Advance publication] Released: August 25, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: We aimed to report the prevalence and correlates of high-risk alcohol consumption and types of alcoholic beverages.

    Methods: The baseline data of the Health Examinees-Gem (HEXA-G) study participants, including 43,927 men and 85,897 women enrolled from 2005 through 2013, were used for analysis. Joinpoint regression was performed to estimate trends in the age-standardized prevalence of alcohol consumption. Associations of demographic and behavioral factors, perceived health-related effects, social relationships, and the diagnostic history of diseases with alcohol consumption were assessed using multinomial logistic regression.

    Results: The prevalence of alcohol consumption remained higher in men during the study period and increased in women. The amount of alcohol consumed has increased in women, especially that from beer and makgeolli, a traditional Korean fermented rice wine. Older participants were less likely to be high-risk drinkers (men and women who drink more than 40 or 20 g/day of alcohol, respectively) and drink Soju, a distilled liquor, and beer, and more likely to drink makgeolli. Educational level was negatively associated with high-risk drinking. However, it was positively associated with the consumption of strong spirits and wine. Smoking was associated with high-risk drinking and the consumption of soju and strong spirits. Engaging in regular exercise and having stress were associated with drinking all types of beverages except for soju.

    Conclusions: Sex-specific trends in alcohol consumption were influenced by demographic, behavioral, and perceived health-related factors. The findings will help improve the understanding of alcohol-related problems and provide evidence for establishing country-specific policies and campaigns in Korea.

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  • Masaaki Yamada, Michikazu Sekine, Takashi Tatsuse
    Article ID: JE20180016
    Published: 2018
    [Advance publication] Released: August 25, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Childhood constipation is prevalent and negatively affects quality of life. Although psychological stress and family environment have been identified as risk factors, few epidemiological studies have examined this issue. We aimed to clarify associations of psychological stress and family environment with childhood constipation in a large-scale epidemiological study.

    Methods: In total, 7,998 children aged 9–10 years from the Toyama Birth Cohort Study completed questionnaires. Constipation was defined as bowel movements “less frequently than once every 2 days”. Children’s lifestyles, including food frequency, psychological stress, family environment, frequency of irritability, unwillingness to attend school, and frequency of interaction with their parents, were analyzed via multivariate logistic regression analysis. Parental employment status and presence at dinner were also examined.

    Results: In total, 312 children (3.9%) experienced constipation. Girls were more likely to experience constipation than boys (5.1% vs 2.8%). In addition, constipation was significantly associated with girl (odds ratio [OR] 1.97; 95% confidence interval [CI], 1.55–2.51), physical inactivity (OR 1.41; 95% CI, 1.01–1.95), overweight (OR 0.58; 95% CI, 0.40–0.85), infrequent fruit (OR 1.94; 95% CI, 1.42–2.66) and vegetable (OR 1.46; 95% CI, 1.03–2.05) consumption, frequent irritability (OR 1.76; 95% CI, 1.24–2.50), unwillingness to attend school (OR 1.66; 95% CI, 1.13–2.43), and infrequent interaction with parents (OR 1.48; 95% CI, 1.06–2.07). Children whose parents were absent at dinner were more likely to experience constipation compared to those whose parents were present at dinner; however, this differences were not statistically significant.

    Conclusion: Psychological stress and infrequent interaction with parents were as strongly associated with childhood constipation as conventional risk factors. Psychological stress and family environment should be more prioritized in caring childhood constipation.

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  • Takafumi Abe, Tsuyoshi Hamano, Keiichi Onoda, Miwako Takeda, Kenta Oku ...
    Article ID: JE20180017
    Published: 2018
    [Advance publication] Released: August 25, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Previous studies have reported an additive effect of moderate-to-vigorous physical activity (MVPA) and sedentary time (ST) on depressive symptoms. However, no studies have been conducted in rural community settings. This cross-sectional study investigated whether the additive effect of MVPA and ST was associated with depressive symptoms in rural Japanese adults.

    Methods: We identified 2,814 participants from health examinations conducted in Shimane, rural Japan, in 2012 and analyzed data from 1,958 participants. We assessed depressive symptoms using the Zung Self-Rating Depression Scale and measured the total time spent on MVPA and ST using a Japanese short version of the International Physical Activity Questionnaire. Poisson regression analysis examined the prevalence ratios (PR) of depressive symptoms in nine category combinations of MVPA level (no, insufficient, or sufficient MVPA) and ST level (high, moderate, or low ST).

    Results: A total of 117 (6.0%) participants had depressive symptoms. Compared with the reference category (no MVPA/high ST), multivariate analysis showed that the likelihood of depressive symptoms was significantly lower in the sufficient MVPA/low ST category (PR 0.23; 95% confidence intervals [CI], 0.08–0.66), insufficient MVPA/low ST category (PR 0.37; 95% CI, 0.16–0.86), and insufficient MVPA/moderate ST category (PR 0.39; 95% CI, 0.17–0.90).

    Conclusion: Analysis of the additive effect of MVPA and ST showed that the combinational category of sufficient MVPA and low ST had the lowest prevalence of depressive symptoms in rural Japanese adults. Moderate ST and low ST showed significantly lower likelihoods of depressive symptoms, regardless of insufficient MVPA.

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  • Tomotaka Sobue
    Article ID: JE20180057
    Published: 2018
    [Advance publication] Released: August 25, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION
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  • John Cologne, Kyoji Furukawa, Eric J. Grant, Robert D. Abbott
    Article ID: JE20170226
    Published: 2018
    [Advance publication] Released: August 11, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The effects, in terms of bias and precision, of omitting non-confounding predictive covariates from generalized linear models have been well studied, and it is known that such omission results in attenuation bias but increased precision with logistic regression. However, many epidemiologic risk analyses utilize alternative models that are not based on a linear predictor, and the effect of omitting non-confounding predictive covariates from such models has not been characterized.

    Methods: We employed simulation to study the effects on risk estimation of omitting non-confounding predictive covariates from an excess relative risk (ERR) model and a general additive-multiplicative relative-risk mixture model for binary outcome data in a case-control setting. We also compared the results to the effects with ordinary logistic regression.

    Results: For these commonly employed alternative relative-risk models, the bias was similar to that with logistic regression when the risk was small. More generally, the bias and standard error of the risk-parameter estimates demonstrated patterns that are similar to those with logistic regression, but with greater magnitude depending on the true value of the risk. The magnitude of bias and standard error had little relation to study size or underlying disease prevalence.

    Conclusions: Prior conclusions regarding omitted covariates in logistic regression models can be qualitatively applied to the ERR and the general additive-multiplicative relative-risk mixture model without substantial change. Quantitatively, however, these alternative models may have slightly greater omitted-covariate bias, depending on the magnitude of the true risk being estimated.

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  • Xuelian Yuan, Fang Yi, Can Hou, Hui Lee, Xiaorong Zhong, Ping Tao, Hui ...
    Article ID: JE20170318
    Published: 2018
    [Advance publication] Released: August 11, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The association between induced abortion and birth control methods (including oral contraceptives and intrauterine devices) and breast cancer may vary among countries, due to the different usage and frequency of birth control methods and induced abortion among countries. A better understanding of this association may help in determining safer birth control methods for Chinese women.

    Methods: A case-control study was conducted with a total of 794 cases and 805 controls. Standardized questionnaires were used to collect information on demographic characteristics, exposure to induced abortion, birth control methods, and other risk factors for breast cancer. Multivariate logistic regression was conducted to explore the association between birth control methods and breast cancer.

    Results: Multivariate logistic regression analyses showed that having a history of medical abortions, ≥3 surgical abortions, or both medical and surgical abortions was associated with an increased risk of breast cancer in post-menopausal women (odds ratio [OR] 2.48; 95% confidence interval [CI], 1.14–5.40). Pre-menopausal women who had used intra-uterine devices (IUDs) for more than 20 years tended to have a lower breast cancer risk than other age-matched pre-menopausal women (OR 0.41; 95% CI, 0.25–0.68). Both pre-menopausal and post-menopausal women who had <20 years exposure to IUDs and those who had used two or more birth control methods (with the exception of women who used IUDs for more than 20 years) tended to have much higher breast cancer risk.

    Conclusion: The relationship between induced abortion and birth control methods and breast cancer was complex, though being exposed to induced abortion and two or more birth control methods in one’s lifetime appeared to be risk factors for breast cancer in Chinese women.

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  • Ehab S Eshak, Koutatsu Maruyama, Hiroyasu Iso, Akiko Tamakoshi
    Article ID: JE20170123
    Published: 2018
    [Advance publication] Released: August 04, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Limited evidence is available on the association of insulin-like growth factors (IGFs) and risk of heart failure in population-based samples. We investigated whether serum IGFs concentrations can predict mortality from heart failure.

    Methods: We conducted a nested case-control study of 39,242 subjects aged 40–79 years who participated in the JACC study, a large Japanese prospective cohort study; participants provided serum samples and were followed up for 9 years. In heart failure cases and age-, sex-, community-, and year of blood withdrawal-matched controls, we measured serum concentrations of IGF-I, IGF-II, and IGF binding protein 3 (IGFBP3) and transforming growth factor (TGF-β1).

    Results: During the follow-up, there were 88 heart failure deaths (44 men and 44 women). Each increment of 1 standard deviation [SD] of IGF-II (120.0 ng/mL in women and 143.7 ng/mL in men) was associated with a 47% reduced risk of mortality from heart failure; multivariable odds ratio was 0.53 (95% confidence interval [CI], 0.30–0.94, P-trend = 0.03). The multivariable odds ratio in the highest quartile of IGFBP3 serum concentrations (≥3.29 µg/mL in women and ≥3.31 µg/mL in men) compared with the lowest (<2.11 µg/mL in women and <2.56 µg/mL in men) was 0.24 (95% CI, 0.05–1.11; P-trend = 0.12). No association was found between serum concentrations of IGF-I or TGF-β1 and risk of heart failure.

    Conclusions: Higher serum concentrations of IGF-II were associated with lower mortality from heart failure, which might suggest a possible role of IGF-II in the occurrence or prognosis of heart failure.

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  • Hyo Kyozuka, Keiya Fujimori, Mitsuaki Hosoya, Seiji Yasumura, Tadahiko ...
    Article ID: JE20170283
    Published: 2018
    [Advance publication] Released: August 04, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: In Japan, mean maternal age at first childbirth is increasing. The aim of this study was to investigate whether maternal age at the first childbirth is a risk factor for preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA).

    Methods: We used the results of Japan Environment and Children’s Study (JECS) who gave birth in 2011–2014. Cases of primiparous singleton pregnancies where the subject was ≥20 years and delivered after 22 weeks were included. All subjects were categorized into five groups according to maternal age: 20–24, 25–29, 30–34, 35–39, and ≥40 years. Adjusted odds ratios (aORs) for PTB (before 37 and 34 weeks), LBW (<2,500 g and <1,500 g), and SGA were calculated using a logistic regression model, with the 20–24-year age group as reference.

    Results: We analyzed 38,412 singleton primiparous pregnancies. The aORs of all outcomes increased in parallel with each maternal age group >30 years. The aORs of PTB before 37 and 34 weeks, LBW <2,500 g, LBW <1,500 g, and SGA in the 30–34-year age group were 1.39 (95% confidence interval [CI], 1.16–1.67), 2.23 (95% CI, 1.45–3.41), 1.34 (95% CI, 1.18–1.53), 2.30 (95% CI, 1.35–3.94), and 1.24 (95% CI, 1.05–1.46), respectively.

    Conclusion: The present study showed that higher maternal age (>30 years) at the first childbirth was an independent risk factor for PTB, LBW, and SGA.

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  • Supot Kamsa-ard, Vor Luvira, Krittika Suwanrungruang, Siriporn Kamsa-a ...
    Article ID: JE20180007
    Published: 2018
    [Advance publication] Released: August 04, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Cholangiocarcinoma (CCA) is a common malignancy in northeastern Thailand. Over the last 4 decades, several policies have been implemented for its prevention, but there has been no update on the trends and relative survival (RS). Our aim was (a) to perform a statistical assessment of the incidence trends of CCA and project future trends, and (b) to estimate relative survival.

    Methods: All cases of CCA diagnosed from 1989 through 2013 were abstracted from the Khon Kaen Cancer Registry (KKCR). A jointpoint regression model was used to estimate the annual percentage change (APC) and to project future trends. We also calculated RS.

    Results: There were 11,711 cases of CCA. The incidence rate increased with an APC of 1.79% (95% confidence interval [CI], −0.2 to 3.8) from 1989 through 2002, and decreased with an APC of −6.09% (95% CI, −8.2 to −3.9) from 2002 through 2013. The projected incidence of CCA should stable over the next 10 years, albeit higher than the world rate. The respective 5-year RS for both sexes for age groups of 30–40, 41–45, 51–60, and 61–98 years was 22.3% (95% CI, 16.8–29.5), 14.3% (95% CI, 12.0–17.0), 8.6% (95% CI, 7.8–10.0), and 7.2% (95% CI, 6.4–8.0).

    Conclusion: The incidence rate of CCA has decreased since 2002, representing a real decline in the risk of CCA. The incidence of CCA is projected to stabilize by 2025. The survival of patients with CCA remains poor.

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  • Marta Conesa, Elisabet Llauradó, Magaly Aceves-Martins, David Moriña, ...
    Article ID: JE20170111
    Published: 2018
    [Advance publication] Released: July 28, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The cost-effectiveness of childhood obesity prevention interventions is critical for their sustained implementation. This study evaluated the cost-effectiveness of the Educació en Alimentació (EdAl) program, a school-based intervention for reducing obesity.

    Methods: Total EdAl program implementation costs and per-child costs were estimated. Cost-effectiveness, defined using the incremental cost-effectiveness ratio (ICER), was estimated as the difference between the intervention and control group costs divided by the obesity-related outcome effects for boys (avoided cases of obesity, obesity prevalence, body mass index [BMI], and BMI z-score units) for each group. As a significant difference (4.39%) in the reduction of obesity prevalence between the intervention and control groups was observed for boys in the EdAl program, the data were calculated only for boys.

    Results: The intervention cost was 24,246.53 € for 1,550 children (15.64 €/child/3 years) or 5.21 €/child/year. The ICERs/boy were 968.66 € to avoid one case of obesity, 3.6 € to reduce the obesity prevalence by 1%, 44.68 € to decrease BMI by one unit, and 65.16 € to reduce the BMI z-score by one unit.

    Conclusions: The cost of reducing the obesity prevalence in boys by 4.39% was 5.21 €/child/year, half the cost proposed by the Spanish Health Ministry, indicating that the EdAl program is cost-effective.

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  • Haruki Momma, Susumu S Sawada, Kiminori Kato, Yuko Gando, Ryoko Kawaka ...
    Article ID: JE20170280
    Published: 2018
    [Advance publication] Released: July 28, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Simple physical fitness test can be a useful potential predictor of type 2 diabetes (T2DM). We examined the association between performances on simple physical fitness tests and the incidence of T2DM.

    Methods: This longitudinal study was conducted in 21,802 nondiabetic Japanese (6,649 women) aged 20 to 92 years, who underwent all physical fitness tests at baseline (April 2001 to March 2002). From April 2001 to March 2008, physical fitness tests, including grip strength, vertical jump, single-leg balance with eyes closed, forward bending, whole-body reaction time, and supine legs-up, were performed every year. Participants had physical fitness tests at least two times during the period. T2DM was also annually determined based on fasting blood glucose, glycated hemoglobin, and self-reported diabetes during the period. Discrete-time logit models were used to examine the influence of the serial level of each physical fitness test on the incidence of T2DM.

    Results: During the entire study period, 972 participants developed diabetes. Lower relative grip strength (grip strength/body weight) and single-leg balance performance were associated with a higher incidence of T2DM. For relative grip strength, as compared with the fourth quartile group, the odds ratios for other groups ranged from 1.16 to 1.56 (P for trend < 0.001). For single-leg balance, the odds ratios ranged from 1.03 to 1.49 (P for trend < 0.001).

    Conclusion: The performance of a simple single-leg balance test as well as that of a grip strength test were negatively associated with the risk of T2DM among Japanese.

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  • Ling Zha, Tomotaka Sobue, Tetsuhisa Kitamura, Yuri Kitamura, Norie Saw ...
    Article ID: JE20170112
    Published: 2018
    [Advance publication] Released: July 21, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: To update the findings of relative risk associated with smoking for all-cause mortality and that for lung cancer by considering longitudinal changes in smoking status during follow-up.

    Methods: Data from the JPHC study of 98,747 middle-aged Japanese adults, which started in 1990–1993, were analyzed. The information on smoking status was obtained from three questionnaire surveys (baseline, the 5th year, and the 10th year after the start of follow-up). A Poisson regression model was used to investigate the impact of smoking on mortality from all causes and lung cancer using two approaches. Model 1 used information only from baseline, while model 2 used the updated smoking status from all three surveys.

    Results: During the 15-year follow-up, 10,702 all-cause deaths (including 870 lung cancer cases) were identified. We compared the results obtained from two models. The relative risks associated with former smokers versus never smokers were 1.42 (95% confidence interval [CI], 1.31–1.54) among men and 1.46 (95% CI, 1.23–1.73) among women for all-cause mortality and 2.98 (95% CI, 2.09–4.24) among men and 1.83 (95% CI, 0.92–3.64) among women for lung cancer mortality, as determined using model 2. All of these were higher than the relative risks obtained from model 1. In addition, former smokers who had quit smoking due to disease during follow-up had a higher mortality risk than continuous smokers did in this study.

    Conclusions: The relative risks of all-cause mortality and mortality due to lung cancer among former smokers be higher than previously documented based on updated smoking status data from repeated surveys.

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  • Sayuri Goryoda, Nobuo Nishi, Haruki Shimoda, Yuki Yonekura, Kiyomi Sak ...
    Article ID: JE20170117
    Published: 2018
    [Advance publication] Released: July 21, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Previous studies have identified poor dietary intake as a health risk affecting survivors of the 2011 Great East Japan Earthquake and Tsunami. We examined the association between different social factors (eg, living conditions and perceptions of community social capital) and dietary intakes among disaster-affected survivors.

    Methods: We studied 6,724 survivors in four municipalities of Iwate Prefecture 3 years after the disaster. Social capital was assessed via four items inquiring about respondents’ perceptions of social cohesion in their communities. Good dietary intake was defined according to the following criteria: intake of staple food ≥three times a day; intake of meat, fish and shellfish eggs, or soybean products ≥twice a day; vegetable intake ≥twice a day; and intake of fruit or dairy products ≥once a day. An individual who did not meet any of these criteria was defined as having poor dietary intake. We adjusted for covariates, including socioeconomic status, marital status, and residential area.

    Results: Poor dietary intake was reported by 31.6% of respondents. Poisson regression analyses revealed that the following factors were related to poor dietary intake: age <65 years (men: prevalence ratio [PR] 1.48; 95% confidence interval [CI], 1.29–1.71 and women: PR 1.55; 95% CI, 1.36–1.77), difficulties in living conditions (men: PR 1.18; 95% CI, 1.00–1.39 and women: PR 1.19; 95% CI, 1.01–1.40), and low perceptions of community social capital (women: PR 1.20; 95% CI, 1.04–1.38).

    Conclusions: Our findings suggest that social capital plays a role in promoting healthy dietary intake among women in disaster-affected areas.

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  • Yosuke Shibata, Toshiyuki Ojima, Mieko Nakamura, Kazuyo Kuwabara, Naok ...
    Article ID: JE20170229
    Published: 2018
    [Advance publication] Released: July 21, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The trend of association between overweight and high serum total cholesterol (TC) among the elderly is unclear. In addition, there is little evidence of risk of underweight for high TC. Therefore, we examined the trend of association of overweight or underweight with high TC among Japanese elderly people using nationwide population-based data.

    Methods: Data of the National Survey on Circulatory Disorders and National Health and Nutrition Survey for 1980, 1990, 2000, and 2010 were used in the analysis. High TC was defined as 220 mg/dL and above. For participants aged ≥50 years, sex-specific odds ratios (ORs) of overweight or underweight compared with normal body mass index participants for high TC were calculated using a logistic regression model adjusted for age, smoking, drinking, exercise, food, and treatment of hyperlipidemia.

    Results: A total of 5,014, 4,673, 5,059, and 2,105 participants enrolled in these surveys in 1980, 1990, 2000, and 2010, respectively. Although overweight was positively and significantly associated with high TC in 1980, the association has gradually weakened since (ORs in 1980 and 2010 were 2.44; 95% confidence interval [CI], 1.83–3.24 and 0.92; 95% CI, 0.66–1.27 among men and 1.43; 95% CI, 1.18–1.72 and 1.08; 95% CI, 0.81–1.44 among women, respectively). While underweight was inversely and significantly associated with high TC in 1980, the association also gradually weakened among women (ORs in 1980 and 2010 were 0.28; 95% CI, 0.12–0.60 and 0.37; 95% CI, 0.10–1.28 among men and 0.39; 95% CI, 0.26–0.57 and 0.96; 95% CI, 0.58–1.57 among women, respectively).

    Conclusions: These findings provide evidence that high TC prevention efforts must expand the target to not only overweight but also to normal and underweight people.

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  • Meishan Cui, Chifa Chiang, Renzhe Cui, Kaori Honjo, Hiroshi Yatsuya, B ...
    Article ID: JE20170127
    Published: 2018
    [Advance publication] Released: July 14, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Epidemiological evidence of dyslipidemia in Pacific Island countries is limited despite the knowledge that non-communicable diseases have a high burden in the region. We aimed to examine the prevalence and correlates of dyslipidemia among residents of Palau.

    Methods: The Palau STEPwise approach to Surveillance (STEPS), which was conducted from 2011 through 2013, comprised three parts: behavioral risk factors; physical measurements; and biochemical tests, covering areas such as blood lipids. We used STEPS-generated data to perform a cross-sectional study of 2,184 randomly selected Palau residents, comprising Palauans and non-Palauans aged 25–64 years.

    Results: The age-adjusted mean BMI was 29.3 kg/m2 in men and 29.9 kg/m2 in women; age-adjusted mean triglycerides value was 182 mg/dL in men and 166 mg/dL in women; and age-adjusted mean cholesterol was 178 mg/dL in men and 183 mg/dL in women. The prevalence of overweight/obesity (BMI ≥25 kg/m2) was 75% in men and 76% in women, and those of hypertriglyceridemia (triglycerides ≥150 mg/dL) and hypercholesterolemia (total cholesterol ≥200 mg/dL) were 48% in men and 41% in women and 18% in men and 23% in women, respectively. Mean values of total cholesterol were 177 mg/dL in Palauan men and 182 mg/dL in non-Palauan men. Mean values of triglycerides were 171 mg/dL in Palauan women and 150 mg/dL in non-Palauan women. Women living in rural areas showed a higher mean value of total cholesterol than those in urban areas.

    Conclusion: We found a high mean BMI and high prevalence of overweight/obesity and hypertriglyceridemia, but low mean total cholesterol and a low prevalence of hypercholesterolemia in Palau. Lipid profiles varied by age, ethnicity, and living area.

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  • Toshitaka Morishima, Yoshifumi Matsumoto, Nobuyuki Koeda, Hiroko Shima ...
    Article ID: JE20170241
    Published: 2018
    [Advance publication] Released: July 14, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The presence of comorbidities in cancer patients may influence treatment decisions and prognoses. This study aimed to examine the impact of comorbidities on overall survival in Japanese patients diagnosed with major solid tumors.

    Methods: To obtain patient-level information on clinical conditions and vital status, we performed a record linkage of population-based cancer registry data from Osaka Prefecture, Japan and administrative data produced under the Diagnosis Procedure Combination (DPC) system. The study population comprised patients who received a primary diagnosis of gastric, colorectal, or lung cancer between 2010 and 2012 at any of five cancer centers. We employed the Charlson Comorbidity Index (CCI) score to quantify the impact of comorbidities on survival. The association between CCI score and survival for each cancer site was analyzed using Cox proportional hazards regression models for all-cause mortality, after adjusting for patient sex, age at cancer diagnosis, and cancer stage.

    Results: A total of 2,609 patients with a median follow-up duration of 1,372 days were analyzed. The most frequent CCI score among the patients was 0 (77.7%), followed by 2 (14.3%). After adjusting for the covariates, we detected a significant association between CCI score and all-cause mortality. The hazard ratios per one-point increase in CCI score were 1.12 (95% confidence interval [CI], 1.02–1.23), 1.20 (95% CI, 1.08–1.34), and 1.14 (95% CI, 1.04–1.24) for gastric, colorectal, and lung cancer, respectively.

    Conclusions: Comorbidities have a negative prognostic impact on overall survival in cancer patients, and should be assessed as risk factors for mortality when reporting outcomes.

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  • Satoshi Seino, Akihiko Kitamura, Yui Tomine, Izumi Tanaka, Mariko Nish ...
    Article ID: JE20170109
    Published: 2018
    [Advance publication] Released: June 30, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Preventing and reducing frailty is an important challenge for Japan in the next decade, especially in metropolitan areas. We launched a community-wide intervention trial (the Ota Genki Senior Project) in 2016 to develop effective community-based strategies for frailty prevention in metropolitan areas. This report describes the study design and baseline survey.

    Methods: This study is a community-wide intervention trial that integrates participatory action research into a cluster non-randomized controlled trial for adults aged 65 years or older living in Ota City, Tokyo. We allocated 3 of 18 districts to an intervention group and the other 15 to a control group. Using a mailed self-administered questionnaire, we conducted a baseline survey of 15,500 residents (8,000 and 7,500 in the intervention and control groups, respectively) from July through August 2016. In addition to socioeconomic status and lifestyle variables, we assessed frailty status (primary outcome) and physical, nutritional, and psychosocial variables (secondary outcomes). Based on the baseline findings, an intervention to improve outcomes will be implemented as participatory action research. Follow-up surveys will be conducted in the same manner as the baseline survey.

    Results: A total of 11,925 questionnaires were returned (76.9% response rate; 6,105 [76.3%] and 5,820 [77.6%] in the intervention and control groups, respectively), and 11,701 were included in the analysis (mean age, 74.3 [standard deviation, 5.5] years; 48.5% were men).

    Conclusions: This study is expected to contribute to development of a prototype of a community-wide frailty prevention strategy, especially in metropolitan areas in Japan. Trial registration: UMIN Clinical Trials Registry (UMIN000026515).

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  • Tin Tin Su, Meram Azzani, Adeoye Philip Adewale, Nithiah Thangiah, Ros ...
    Article ID: JE20170183
    Published: 2018
    [Advance publication] Released: June 30, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The aim of this research is to assess the level of physical activity (PA) in relation to different socio-economic factors and to examine the effect of the recommended level of PA on the domains of quality of life (QoL) among residents of low-income housing in the metropolitan area of Kuala Lumpur, Malaysia.

    Methods: This was a cross-sectional study that included 680 respondents from community housing projects. Reported PA was assessed using the Global Physical Activity Questionnaire (GPAQ) short form version 2. The SF-12v2 was administered to assess the health-related QoL (HRQoL) among the study population. Respondents were grouped into “active” and “insufficient” groups according to reported weekly PA level. One-way analysis of variance, analysis of co-variance, and multiple linear regression were used in the analysis.

    Results: Overall, 17.6% (95% CI, 14.3–20.9) of the respondents did not achieve the recommended levels of PA (≥600 metabolic equivalent [MET]-minutes week−1). Level of achieving recommended PA was higher among younger participants, females, members belonging to nuclear families, and in self-employed participants. The group that fulfilled recommended PA levels (active) has higher levels of QoL in all domains except physical functioning.

    Conclusions: Almost one out of five low-income urban residents were physically inactive. In addition, individuals who attained recommended PA levels had better scores on some domains of HRQOL than those who did not. Our findings call for tailor-made public health interventions to improve PA levels among the general population and particularly for low-income residents.

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  • Airi Amemiya, Takeo Fujiwara
    Article ID: JE20170220
    Published: 2018
    [Advance publication] Released: June 30, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: The respiratory tract of children in low-income families is more likely to be exposed to toxins, which may lead to poor lung function. The purpose of this study was to elucidate the impact of low household income on lung function among children and adolescents in Japan.

    Methods: We analyzed a population-based sample of 1,224 children aged 5 to 17 years old from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE). Forced expiratory volume in 1 s (FEV1) and in 6 s (FEV6) was measured. Annual household income and other potential covariates were assessed through a questionnaire. Low household income was defined as less than 3 million yen (approximately 27,000 United States dollars [USD]) per year. Multivariate regression analysis was used to adjust for potential covariates.

    Results: We observed statistically significantly lower FEV1:FEV6 ratio with children in lowest-income families compared with those in highest-income families, after adjusting for child’s age and sex (coefficient = −0.082; 95% confidence interval [CI], −0.131 to −0.034). After adjusting for other covariates, including parental smoking status and parental diagnosis of asthma, a similar trend remained (coefficient = −0.054; 95% CI, −0.109 to 0.001).

    Conclusions: Children in low-income families showed significantly lower lung function than those in high-income families. Prevention and early intervention are necessary to help the development of lung function among children living in low-income families.

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  • Hirokazu Tanaka, Noriko Ihana-Sugiyama, Takehiro Sugiyama, Mitsuru Ohs ...
    Article ID: JE20170155
    Published: 2018
    [Advance publication] Released: June 23, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Several epidemiological studies have determined the relationship between diabetes and the incidence and/or prevalence of recently identified comorbid conditions (cancer, periodontal disease, fracture, cognitive impairment, and depression). These relationships may vary by country or race/ethnicity. We aimed to systematically review studies in this field conducted with the Japanese population because such a review in the Japanese population has never been undertaken.

    Methods: We conducted systematic literature searches in PubMed and Ichushi-Web databases for studies published until December 2016. Studies comparing the incidence and/or prevalence of the comorbidities among the Japanese population were included. The studies were classified as integrated analyses, cohort studies, case-control studies, or cross-sectional studies.

    Results: We identified 33 studies (cancer: 17, periodontal disease: 5, fracture: 5, cognitive impairment: 4, and depression: 2). Although several cohort studies and meta-analyses had assessed the development of cancer in diabetes, there was scant epidemiological evidence for the other conditions. Indeed, only one cohort study each had been conducted for periodontal disease, fracture, and cognitive impairment, whereas other evidence was cross-sectional, some of which was induced from baseline characteristic tables of studies designed for other purposes.

    Conclusion: In Japan, there is insufficient evidence about the relationship between diabetes and the incidence/prevalence of periodontal disease, fracture, cognitive impairment, and depression. By contrast, several cohort studies and integrated analyses have been conducted for the relationship with cancer. Further studies should be undertaken to estimate the contribution of diabetes on the incidence/prevalence of comorbidities that may be specific to the Japanese population.

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  • Junko Saito, Naoki Kondo, Masashige Saito, Daisuke Takagi, Yukako Tani ...
    Article ID: JE20170230
    Published: 2018
    [Advance publication] Released: June 23, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: We explored the distinct trajectories of functional decline among older adults in Japan, and evaluated whether the frequency of outings, an important indicator of social activity, predicts the identified trajectories.

    Methods: We analyzed data on 2,364 adults aged 65 years or older from the Japan Aichi Gerontological Evaluation Study. Participants were initially independent and later developed functional disability during a 31-month follow-up period. We used the level of long-term care needs certified in the public health insurance system as a proxy of functional ability and linked the fully tracked data of changes in the care levels to the baseline data. A low frequency of outings was defined as leaving one’s home less than once per week at baseline. We applied a growth mixture model to identify trajectories in functional decline by sex and then examined the association between the frequency of outings and the identified trajectories using multinomial logistic regression analysis.

    Results: Three distinct trajectories were identified: “slowly declining” (64.3% of men and 79.7% of women), “persistently disabled” (4.5% and 3.7%, respectively), and “rapidly declining” (31.3% and 16.6%, respectively). Men with fewer outings had 2.14 times greater odds (95% confidence interval, 1.03–4.41) of being persistently disabled. The association between outing frequency and functional decline trajectory was less clear statistically among women.

    Conclusions: While the majority of older adults showed a slow functional decline, some showed persistent moderate disability. Providing more opportunities to go out or assistance in that regard may be important for preventing persistent disability, and such needs might be greater among men.

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  • Kenichi Mori, Keiko Wada, Kie Konishi, Yuko Goto, Fumi Mizuta, Sachi K ...
    Article ID: JE20170278
    Published: 2018
    [Advance publication] Released: June 23, 2018
    JOURNALS OPEN ACCESS ADVANCE PUBLICATION

    Background: Cedar pollinosis is one of the most prevalent forms of seasonal allergic reaction in Japan. Only one prospective study has examined the association between cedar pollinosis and mortality. Using a symptom-based questionnaire on cedar pollinosis, we investigated the association of cedar pollinosis with all-cause and cause-specific mortality.

    Methods: Data came from the Takayama Study, which recruited residents aged ≥35 years in 1992 from Takayama city in Gifu Prefecture, Japan. The current study used information on cedar pollinosis that was obtained from the second survey in 2002. A total of 12,471 persons who were 45–80 years old and had no history of cancer, coronary heart disease, or stroke responded to a questionnaire asking about four symptoms related to cedar pollinosis. Mortality and migration data were obtained throughout the follow-up period up to March 2013. Cox proportional hazard models were used to examine the relation between cedar pollinosis and mortality.

    Results: A total of 1,276 persons died during follow-up period. Among these, there were 504 neoplasm, 278 cardiovascular, and 181 respiratory deaths. After adjusting for potential confounders, cedar pollinosis was associated with significantly lower all-cause mortality (hazard ratio [HR] 0.79; 95% confidence interval [CI], 0.65–0.95) and respiratory mortality (HR 0.38; 95% CI, 0.18–0.82). There was no significant association between cedar pollinosis and mortality due to neoplasm or cardiovascular disease.

    Conclusions: We found an inverse association between cedar pollinosis and the risk of all-cause and respiratory mortality. Further research is needed to elucidate the association between cedar pollinosis and mortality.

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