Background: It has been reported that chronic inflammation may play an important role in the pathogenesis of several serious diseases and could be modulated by diet. Recently, the Dietary Inflammatory Index (DII^®) was developed to assess the inflammatory potential of the overall diet. The DII has been reported as relevant to various diseases but has not been validated in Japanese. Thus in the present study, we analyzed the relationship between DII scores and high-sensitivity C-reactive protein (hs-CRP) levels in a Japanese population.

Methods: Data of the National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged 2010 (NIPPON DATA2010), which contained 2898 participants who aged 20 years or older from the National Health and Nutrition Survey of Japan (NHNS2010), were analyzed. Nutrient intakes derived from one-day semi-weighing dietary records were used to calculate DII scores. Energy was adjusted by residual method. Levels of hs-CRP were evaluated using nephelometric immunoassay. Multiple linear regression analyses were performed.

Result: After adjusting for age, sex, smoking status, BMI and physical activity, a significant association was observed between DII scores and log(CRP+1) (standard regression coefficient=0.05, p<0.01). And although it was not statistically significant, the positive association was consistently observed in almost all age-sex subgroups and the non-smoker subgroup.

Conclusions: The current study confirmed that DII score was positively associated with hs-CRP in Japanese.

Background: Abusive head trauma (AHT) is the leading cause of fatal maltreatment among young children. The incidence of AHT in Japan, however, remains unknown. This study examined the incidence and distribution of age in months among young children under 12 months old hospitalized with intracranial injury in Japan.

Methods: We conducted multicenter cross-sectional study for children under 36 months old admitted with intracranial injury to hospitals that employed the Diagnostic Procedure Combination (DPC) payment system between 2010 and 2013. Presumptive and possible AHT were defined by the combination of ICD-10 codes modified from the coding system recommended by the US Centers for Disease Control and Prevention.

Results: The average incidence was 7.2 (95% confidence interval [CI]: 7.18-7.26) for presumptive and 41.7 (95% CI: 41.7-41.8) for possible AHT per 100,000 children less than 12 months old from 2010 to 2013. The distributions of age in months for both presumptive AHT and possible AHT had peaks at around two and eight months.

Conclusions: This is the first study to report the incidence of hospitalized children with presumptive and possible AHT using population-based data. Further datasets are needed to evaluate the incidence and specific preventive strategies to prevent AHT in infants during the months of highest risk.

Background: Lifestyle and life-environment factors have undergone drastic changes in Japan over the last few decades. Further, many molecular epidemiologic studies have reported that genetic, epigenetic and other biomarker information may be useful in predicting individual disease risk.

Methods: Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT) was launched in 2011 to identify risk factors for lifestyle-related disease, elucidate factors which extend healthy life expectancy, and contribute toward personalized healthcare based on our more than 20 years’ experience with the JPHC Study. Between 2011 and 2016, a baseline survey was conducted at 16 municipalities in 7 prefectures across the country. A self-administered questionnaire was distributed to all registered residents aged 40-74 which mainly asked about lifestyle factors, such as socio-demographic situation, personal medical history, smoking, alcohol and dietary habits. We obtained informed consent from each participant to participate in this long follow-up study of at least 20 years, including consent to the potential use of their residence registry, medical records, medical fee receipts, care insurance etc., and to the provision of biospecimens (blood and urine), including genomic analysis.

Results and Conclusion: As of December 31, 2016, we have established a population-based cohort of 115,385 persons (Response rate 44.1%), among whom 55,278 (47.9% of participants) have provided blood and urine samples. The participation rate was slightly higher among females and in the older age group. In conclusion, we have established a large-scale population-based cohort for next-generation epidemiological study in Japan.

Background: A growing number of epidemiology studies have shown that poor oral health is associated with an increased incidence of functional disability. However, there are few studies in which the confounding bias is adjusted appropriately. In this study, it was examined whether dental status is associated with functional disability in elderly Japanese using a 13-year prospective cohort study after elimination of confounding factors with propensity score matching.

Methods: Participants were community-dwelling Japanese aged 70 years or older who lived in the Tsurugaya district of Sendai (n = 838). The number of remaining teeth (over 20 teeth/0-19 teeth) was defined as the exposure variable. The outcome was the incidence of functional disability, defined as the first certification of long-term care insurance (LTCI) in Japan. The variables that were used to determine propensity score matching were age, sex, body mass index (BMI), medical history (stroke, hypertension, myocardial infarction, cancer, and diabetes), smoking, alcohol consumption, educational attainment, depression symptoms, cognitive impairment, physical function, social support, and marital status.

Results: As a result of the propensity score matching, 574 participants were selected. Participants with 0-19 teeth were more likely to develop functional disability than those with 20 or more teeth (hazard ratio, 1.33; 95% confidence interval, 1.01-1.75).

Conclusions: In this prospective cohort study targeting community-dwelling older adults in Japan, less than 20 teeth was confirmed to be an independent risk factor for functional disability even after conducting propensity score matching. This study supports previous publications showing that oral health is associated with functional disability.

Background: The association of sensory loss with mortality remains unclear. We aimed to explore the association of hearing loss (HL), visual loss (VL), and dual sensory loss (DSL) with survival.

Methods: Data came from the Komo-Ise study cohort in Gunma prefecture, Japan, where the community-dwelling residents aged 40-69 years were followed up from 1993 to 2010. 9522 individuals who answered the follow-up questionnaires in 2000 (average age 64 (range 47 to 77) in 2000) were analyzed. The primary exposures were "HL only," "VL only," or " DSL” with "no HL/VL" as the reference. These sensory loss statuses were assessed by asking the difficulty in hearing conversation or reading newspaper even with aids in the follow-up questionnaires in 2000. All-cause and cause-specific mortality were ascertained from linkage to death certificate data. Cox proportional hazards models adjusting for confounders including demographic factors, socioeconomic status, and health status were used. Potential mediators (depression, walking disability, and social participation) were additionally adjusted for.

Results: 1105 deaths occurred over the 10-year follow-up. After adjustment for the potential confounders, HL and DSL were associated with increased all-cause mortality (hazard ratio of 1.74 (95% CI, 1.18–2.57) and 1.63 (95% CI, 1.09–2.42), respectively). Potential mediators explained a modest portion of the association. As for cause-specific mortality, HL was associated with increased cancer mortality, while VL and DSL were associated with increased cardiovascular disease mortality.

Conclusions: Self-reported HL and DSL may be risk factors of mortality among middle-aged or elderly Japanese populations.

Background: Metal exposures could possibly affect allergic responses in pregnant women, although no studies have yet shown a clear relationship between the two, and such exposures might also affect the development of allergic diseases in children.

Methods: We investigated the relationship between metal concentrations in whole blood and immunoglobulin E (IgE; total and specific) in 14,408 pregnant women who participated in the Japan Environment and Children’s Study. The subjects submitted self-administered questionnaires, and blood samples were collected from them twice, specifically, during the first trimester and again during the second/third trimester. Concentrations of the metals Cd, Pb, Hg, Se, and Mn, as well as serum total and allergen-specific IgEs for egg white, house dust-mites (HDM), Japanese cedar pollen (JCP), animal dander, and moth, were measured. Allergen-specific IgE(s) were divided based on concentrations <0.35 or ≥0.35 UA/mL, and the metal levels were divided into quartiles.

Results: Multivariable logistic regression analysis showed that there was a significant negative correlation between HDM- and animal dander-specific IgEs and Hg and Mn concentrations. Conversely, there was a significant positive relationship between JCP-specific IgE and Hg and Se concentrations.

Conclusions: Metal exposures may be related to both increases and decreases in allergen-specific IgEs in pregnant women.

Objectives: Distributions of serum pepsinogen (PG) values were assessed in Helicobacter pylori-infected and non-infected junior high school students (aged 12-15 years) in Japan.

Methods: All junior high school students (1,225 in total) in Sasayama city, who were basically healthy, were asked to provide urine and serum samples, which were used to measure urine and serum H. pylori antibodies using ELISA kits and PG values. The subjects, whose urine and serum antibodies were both positive, were considered H. pylori infected.

Results: Of the 187 subjects who provided both urine and blood samples, 8 were infected, 4 had discrepant results, 4 had negative serum antibody titers no less than 3.0 U/ml, and 171 were non-infected. In the H. pylori non-infected subjects, the median PG I and PG II values and PG I to PG II ratio (PG I/II) were 40.8 ng/ml, 9.5 ng/ml and 4.4, respectively, whereas in the infected subjects, these values were 55.4 ng/ml, 17.0 ng/ml and 3.3, respectively, (each p<0.01). In the non-infected subjects, PG I and PG II were significantly higher in males than in females (p<0.01).

Conclusions: The PG I and PG II values were higher, and the PG I/II was lower in H. pylori infected students than in non-infected students. In H. pylori non-infected students, males showed higher PG I and PG II values than females. The distributions of PG values in junior high school students differed from those in adults.

Background: Few studies have investigated the effects of Okinawan vegetable consumption on the risk of incident stroke and coronary heart disease. This study aimed to examine associations of vegetable, fruit, and Okinawan vegetable consumption with risk of incident stroke and coronary heart disease in the Japanese population of Okinawa.

Methods: Study design was a prospective cohort study. During 1995-1998, a validated food frequency questionnaire was administered in two study areas to 16,498 participants aged 45-74 years. In 217,467 person-years of follow-up until the end of 2012, a total of 839 stroke cases and 197 coronary heart disease cases were identified.

Results: No statistically significant association between total Okinawan vegetable consumption and risk of stroke and coronary heart disease was obtained: the multivariable adjusted hazard ratios for the highest versus lowest tertile of consumption were 1.09 (95% confidence interval, 0.93-1.29; p for trend = 0.289) in model 2. Total vegetable and fruit and specific Okinawan vegetable consumption were also not statistically significantly associated with risk of cardiovascular outcomes.

Conclusions: This study demonstrated that consumption of total vegetable and fruit, total Okinawan vegetables, and specific Okinawan vegetables in Japanese residents of Okinawa was not associated with risk of incident stroke and coronary heart disease.

Background: To examine trends in serum lipids in population in Northwestern Xinjiang between 1998 and 2015 and to provide clues for future prevention.

Methods: We enrolled 5,142 adults aged ≥30 years from seven independent cross-sectional studies conducted in 1998–2000, 2007–2008, and 2015. Blood lipid profiles, such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), were measured.

Results: The mean age was 48.5 years in 1998–2000, 47.9 years in 2007–2008, and 53.7 years in 2015. There was a declining trend in the prevalence of dyslipidemia among adults in northwestern Xinjiang. Mean LDL-C decreased during the same period, while mean HDL-C showed the opposite trend. Mean TC was 4.79 mmol/L in 1998–2000, 5.17 mmol/L in 2007–2008, and 4.59 mmol/L in 2015. The trend of mean TG was similar to that of TC. The prevalence of dyslipidemia was closely related with male gender, Mongolian ethnicity, hypertension, obesity, elevated fasting blood glucose, smoking, and drinking.

Conclusion: Between 1998 and 2015, favorable trends in lipid levels have occurred among adults of Northwestern Xinjiang. However, further efforts are needed.

The Circulatory Risk in Communities Study (CIRCS) is an ongoing community-based epidemiological study of lifestyle-related disease, involving dynamic prospective cohorts of approximately 12,000 adults from 5 communities of Japan: Ikawa, Ishizawa and Kita-Utetsu (Akita), Minami-Takayasu (Osaka), Noichi (Kochi), and Kyowa (Ibaraki). One of the most notable features of CIRCS is that it is not only an observational cohort study to identify risk factors for cardiovascular diseases (CVD) such as stroke, coronary heart disease, and sudden cardiac death, but it also involves prevention programs for CVD. Using basic, clinical, epidemiological, and statistical techniques, CIRCS has clarified characteristics of CVD and the related risk factors to develop specific methodologies towards CVD prevention in Japanese middle-aged or older adults for more than half a decade.

Background: The association of body mass index (BMI) with risks of ischemic stroke subtypes have not been established.

Methods: Cumulative average BMI was calculated using self-reported body weight and height obtained from baseline (Cohort I in 1990, and Cohort II from 1993–1994) and 5- and 10-year questionnaire surveys of Japan Public Health Center-based prospective (JPHC) study. A total of 42,343 men and 46,413 women aged 40–69 years were followed-up for the incidence of lacunar, large-artery occlusive, and cardioembolic strokes. A sub-distribution hazard model was used to estimate sub-distribution hazard ratios (SHRs) and the 95% confidence intervals (CIs).

Results: During a median of 20.0 years of follow-up, we documented 809 and 481 lacunar, 395 and 218 large-artery occlusive, and 568 and 298 cardioembolic strokes in men and women, respectively. After adjustment for baseline age, updated smoking, alcohol consumption, leisure-time physical activity, and histories of hypertension, dyslipidemia, and diabetes mellitus, cumulative average BMI was positively linearly associated with lacunar (trend P = 0.007), large-artery occlusive (trend P = 0.002), and cardioembolic (trend P < 0.001) strokes in men, and with lacunar (trend P < 0.001) and large-artery occlusive (trend P = 0.003) strokes in women. There were approximately two-fold excess risk of cardioembolic stroke in both sexes and of lacunar and large-artery occlusive strokes in women for cumulative average BMI ≥30 kg/m² compared to BMI 23–<25 kg/m².

Conclusion: Cumulative average BMI showed a positive linear effect on sub-distribution hazards of lacunar, large-artery occlusive, and cardioembolic strokes in both sexes, except for cardioembolic stroke in women.

Background: Little is known about the association between the anxiety toward the effects of radiation on reproduction caused by the Fukushima nuclear accident and the birth rate of people in Fukushima. Therefore, we examined changes and associated factors of future pregnancy intention among mothers in Fukushima Prefecture.

Methods: Using data from three postal surveys among women who registered their pregnancies in the prefecture (N = 6,751 in 2012, N = 6,871 in 2013, and N = 6,725 in 2014), we analyzed the factors associated with women’s intention of future pregnancy using multivariable logistic regression models.

Results: The proportion of mothers with pregnancy intention increased from 53.5% in 2012 to 57.9% in 2014, especially among multiparas (P for trend <0.001). Factors inversely associated with pregnancy intention of both groups were older maternal age (adjusted odds ratio [aOR] 0.92 for primipara and 0.87 for multipara), poor subjective health (aOR 0.75 and 0.81, respectively), and presence of depressive symptoms (aOR 0.71 and 0.79, respectively) (P < 0.01 for all items). In addition, not living with husband (aOR 0.24), dissatisfaction with obstetrical care (aOR 0.89) and child abnormalities (aOR 0.72) were inversely associated with pregnancy intention among primiparas, while receiving infertility treatment (aOR 2.05) was positively associated among multiparas (P < 0.01 for all items). A separate analysis of 2012 and 2013 data showed that concern about radiation contamination of breast milk was associated with pregnancy intention among primiparas (aOR 0.61, P < 0.001).

Conclusions: Mothers’ concern about radiation was associated with lower pregnancy intention, especially among primiparas. Providing quality obstetrical and mental health care and parenting support may be the keys to maintaining the temporal increase in fertility.

Background: Current trends in serum lipid levels among children are likely to be important predictors of future cardiovascular disease prevalence. However, no studies have examined trends in low-density lipoprotein cholesterol (LDL-C) levels in Japanese children.

Methods: We investigated trends in LDL-C levels from 2008 to 2017 and HDL-C levels from 2007 to 2017 in a population of 10- and 13-year-old children in Fukuroi City, Japan. We analyzed 17838 children, accounting for 93.8% of all fifth and eighth graders in the entire city. Adverse lipid levels were defined as follows: 130 mg/dL or higher for LDL-C, and lower than 40 mg/dL for HDL-C. The Jonckheere-Terpstra and Cochran-Armitage tests were used to evaluate secular trends in mean serum lipid levels and prevalence of dyslipidemia, respectively.

Results: There were no significant trends in BMI during the study period. In children aged 10 years, serum levels of LDL-C and HDL-C showed significant positive associations with calendar year during the study period for both sexes. A significant increase in HDL-C levels was observed in girls aged 13 years. On the other hand, no significant trends were observed in the prevalence of high LDL-C or low HDL-C regardless of sex or age, while the prevalence of high non-HDL-C showed a significant increase in boys.

Conclusions: In the Fukuroi population, serum levels of LDL-C and HDL-C slightly increased in both boys and girls aged 10 years, and HDL-C levels slightly increased in girls aged 13 years during the past decade.

Background: The association between decline in handgrip strength from midlife to late-life and dementia is unclear.

Methods: Japanese community-dwellers without dementia aged 60 to 79 (i.e., individuals in late-life; mean age, 68 years) were followed for 24 years (1988–2012) (n=1,055); 835 of them had participated in a health examination in 1973–1974 (mean age, 53 years), and these earlier data were used for the midlife analysis. Using a Cox proportional hazards model, we estimated the risk conferred by a decline in handgrip strength over a 15-year period (1973-74 to 1988) from midlife to late-life on the development of total dementia, Alzheimer’s disease (AD) and vascular dementia (VaD) over the late-life follow-up period from 1988 to 2012.

Results: During the follow-up, 368 subjects experienced total dementia. The age- and sex-adjusted incidence of total dementia increased significantly with greater decline in handgrip strength (increased or unchanged handgrip strength [≥+0%] 25.1, mildly decreased [-14 to -1%] 28.4, and severely decreased [≤-15%] 38.9 per 1,000 person-years). A greater decline in handgrip strength was significantly associated with higher risk of total dementia after adjusting for potential confounding factors; subjects with severely decreased handgrip strength had 1.51-fold (95% confidence interval=1.14-1.99, p<0.01) increased risk of total dementia compared to those with increased or unchanged handgrip strength. Similar significant findings were observed for AD, but not for VaD.

Conclusions: Our findings suggest that a greater decline in handgrip strength from midlife to late-life is an important indicator for late-life onset of dementia.

Background: Considering the rate of growth of the older population in several countries, accidental falls in older cyclists are expected to increase. However, the prevalence and correlates of bicycle-related falls (BR-falls) are unknown. The aim of the present study was to explore the characteristics of BR-falls, focusing on the risk factors.

Methods: Seven-hundred and ninety-one older adults participated in a comprehensive baseline assessment including questions on bicycle use, BR-falls, lifestyle, and physical and cognitive evaluations. A cyclist was defined as a person who cycled at least a few times per month. The incidence of BR-falls in participants who did not report BR-falls at baseline was again ascertained three years later. Logistic regression analyses examined the predictors of BR-falls incidence.

Results: At baseline, 395 older adults were cyclist and 45 (11.4%) of them had experienced BR-falls. Adjusted regression analysis showed that slower gait velocity, shorter one-leg standing time, and experience of falls (i.e., non-BR-falls) were associated with BR-falls. Among the 214 cyclists who did not report BR-falls at baseline and who participated in both baseline and follow-up assessments, 35 (16.4%) cyclists experienced BR-falls during the 3-year follow-up. Adjusted regression analysis revealed that higher body mass index and non-BR-falls were predictors of future incident of BR-falls, independent of physical function.

Conclusions: Our results showed that experience of falls, irrespective of bicycling, is an independent correlate and risk factor of BR-falls. This suggests that experience of falls and BR-falls may share the same risk factors.

Background: This study aimed to examine the contextual effects of community-level social capital on the onset of depressive symptoms using a longitudinal study design.

Methods: We used questionnaire data from the 2010 and 2013 waves of the Japan Gerontological Evaluation Study that included 14,465 men and 14,600 women aged over 65 years from 295 communities. We also used data of a three-wave panel (2006–2010–2013) to test the robustness of the findings (n = 7,424). Using sex-stratified multilevel logistic regression, we investigated the lagged associations between three scales of baseline community social capital and the development of depressive symptoms.

Results: Community civic participation was inversely associated with the onset of depressive symptoms (men: adjusted odds ratio [AOR] 0.93; 95% confidence interval [CI], 0.88–0.99 and women: AOR 0.94; 95% CI, 0.88–0.997 per 1 standard deviation unit change in the score), while no such association was found in relation to the other two scales on social cohesion and reciprocity. This association was attenuated by the adjustment of individual responses to the civic participation component. Individual-level scores corresponding to all three community social capital components were significantly associated with lower risks for depressive symptoms. The results using the three-wave data set showed statistically less clear but similar associations.

Conclusions: Promoting environment and services enhancing to community group participation might help mitigate the impact of late-life depression in an aging society.

Background: In the present study, we examined the trends of premature mortality due to kidney and bladder cancers among the Japanese population from 1980 through 2010.

Methods: Mortality data were obtained from the World Health Organization mortality database. Years of life lost (YLL) was estimated using Japanese life tables. Average lifespan shortened (ALSS) was calculated and defined as the ratio of years of life lost relative to the expected lifespan.

Results: Over the study period, the age-standardized rates to the World Standard Population for deaths from kidney and bladder cancers were stable. The average years of life lost (AYLL) measure shows decreases of about four and six years of life for kidney cancer in men and women respectively, and decreases of about two years of life for bladder cancer in both sexes. The ALSS shows that patients with kidney cancer lost 21.0% and 24.7% of their lifespan among men and women in 1980, whereas respective losses were 15.3% and 15.8% in 2010. Also, patients with bladder cancer on average lost 13.5% in men and 14.2% in women in 1980 and 10.8% in men and 11.1% in women in 2010.

Conclusions: Our study shows favorable trends in premature mortality for kidney and bladder cancers in Japan over a 30-year period; however, patients with bladder cancer on average lost a smaller proportion of their lifespan compared to those with kidney cancer. The development of a novel ALSS measure is convenient in examination of the burden of premature mortality over time.

Background: Studies on sex-specific socioeconomic gradients in objectively evaluated diabetes among older adults are scarce.

Methods: We used cross-sectional data of 9,893 adults aged 65 years and older in Aichi Prefecture without long-term care insurance from the Japan Gerontological Evaluation Study (JAGES) in 2010 (Response rate: 66.3%). We collected demographic, socioeconomic (income, years of education, and longest occupation) and behavioral information using a mail-in self-reported survey. Blood samples for the objectively evaluated diabetes and self-reported medical history were collected at annual municipal health checkups. Poisson regression analysis stratified by sex with multiple imputations was conducted to calculate prevalence ratio and 95% confidence interval.

Results: A clear income gradient in diabetes prevalence was observed among women, from 11.7% in the lowest income quartile (Q1) to 7.8% in the highest (Q4). Among men, the findings were 17.6% in Q1 to 15.1% in Q4. The prevalence ratios for diabetes with incomes Q1 to Q4 were 1.43 (95% confidence interval [CI], 1.07–1.90) for women and 1.16 (95% CI, 0.90–1.50) for men after adjusting for age and other socioeconomic factors. Even after adjusting for marital status, body mass index, other metabolic risk factors, and lifestyle factors, the income-based gradient remained among women. Education and occupation were not significantly associated with diabetes in the study population.

Conclusions: Only women showed an income-based gradient in diabetes. Monitoring income gradient in diabetes is important in public health actions, even in older populations. Future longitudinal and intervention studies should evaluate the causal link of income to diabetes onset, determine the mechanisms of the potential sex differences in the income/diabetes association, and identify ways to mitigate the income-based inequality.

Background: Although meals that combine a staple food, main dish, and side dish (balanced meals) are recommended in Japan, the health effects of such meals are unclear. We investigated the association of frequency of eating balanced meals with frailty among community-dwelling older Japanese.

Methods: We analyzed data from 912 persons aged 65 years or older who participated in the Hatoyama Cohort Study or Kusatsu Longitudinal Study. The frequency of eating two or more balanced meals daily was self-reported as ≤1 day/week, 2 or 3 days/week, 4 or 5 days/week, and daily. Frailty was defined as the presence of at least three, and pre-frailty as the presence of one or two, of the following criteria: weight loss, muscle weakness, exhaustion, slowness, and low physical activity. Adjusted logistic regression was used to study associations of frequency of balanced-meal consumption with frailty (prefrailty and frailty combined) and frailty criteria.

Results: Participants reporting a frequency of balanced-meal consumption of ≤2 or 3 days/week had a higher prevalence of frailty (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.21–2.64) than did those reporting a frequency of daily. Lower frequency of balanced-meal consumption was also associated with higher prevalences of weight loss (OR, 4.10; 95% CI, 1.90–8.85), exhaustion (OR, 6.35; 95% CI, 2.49–16.17), and low physical activity (OR, 1.92; 95% CI, 1.22–3.01).

Conclusions: Our findings suggest that more frequent twice daily consumption of meals with a staple food, main dish, and side dish decreases the risks of prefrailty and frailty.

Background: Lung cancers are classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer due to their different treatment and prognosis. Although many studies have reported the specific survival of SCLC patients treated at cancer hospitals, survival from population-based data has rarely been reported.

Methods: We analyzed survival of SCLC cases diagnosed from 1993 through 2006 from a population-based cancer registry of six prefectures. To assess trends in SCLC survival, we defined three periods that mirrored developments in SCLC treatment: period 1, 1993–1998; period 2, 1999–2001; and period 3, 2002–2006. Assessments were based on relative survival (RS), excess hazard, and conditional survival.

Results: A total of 10,911 SCLC patients were analyzed. Five-year RS among limited disease SCLC (LD-SCLC) in periods 1 to 3 was 16.8%, 21.1%, and 21.4%, respectively. Five-year RS among extensive disease SCLC (ED-SCLC) in periods 1 to 3 was 2.3%, 2.8%, and 2.7%, respectively. Improvement in 5-year RS in periods 2 and 3 compared with period 1 was significant among both LD- and ED-SCLC patients (all P < 0.001). Conditional 5-year RS of LD-SCLC increased from 21% at year 0 to 73% at year 5, while that of ED-SCLC was 3% at year 0 and 53% at year 5.

Conclusions: The prognosis of SCLC patients improved from 1999–2001 but plateaued in 2002–2006, after which no further significant improvement was seen. Continuous survey based on population-based data is helpful in monitoring the impact of developments in treatment.

Background: Some studies have indicated that female birth and multiple births were risk factors for nausea and vomiting during pregnancy (NVP). The results, however, were conflicting. Our study was conducted to evaluate the association of maternal NVP with fetal sex in singleton and twin pregnancies.

Methods: We used the data set from a birth cohort study, the Japan Environment and Children’s Study (JECS). In the self-administered questionnaire, participants were asked whether they experienced NVP prior to 12 gestational weeks. Main outcome measures were the presence of NVP and severity of NVP. We estimated the association of fetal sex and birth plurality with NVP using logistic regression analysis, followed by interaction analysis.

Results: Of 91,666 women, 75,828 (82.7%) experienced at least some symptoms of NVP and 10,159 (11.1%) experienced severe NVP. Women with female pregnancies and twin pregnancies had higher odds for the presence of NVP and severe NVP compared to women with male pregnancies and singleton pregnancies, respectively. Moreover, of mothers with twin pregnancies, higher odds for the presence of NVP and severe NVP were reported when one or both infants were female, compared to those in which both infants were male. There was no significant interaction between fetal sex and birth plurality.

Conclusions: Female sex birth and multiple births are risk factors for the presence of NVP, and especially for severe NVP without interaction. These findings suggest that a factor abundant in the female fetus associates with the severity of NVP.

Background: Severe pediatric cases of hand, foot, and mouth disease (HFMD), herpangina (HA), and associated complications caused by enterovirus 71 (EV71) infection have brought substantial public health impact in Asia. This study aimed to elucidate the epidemiology of these pediatric cases in Japan.

Methods: A nationwide survey was conducted using stratified random sampling of hospital pediatric departments. We estimated the number of inpatients with HFMD, HA, and associated complications between April 1 and September 30, 2010, during which EV71 was circulating predominantly. Factors associated with severe cases with ≥7 days of admission, sequelae, or outcome of death were analyzed using multivariate logistic regression.

Results: During the 6-month epidemic period, the number of pediatric inpatients aged <15 years was about 2,900 (estimated cumulative incidence of hospitalized cases: 17.0 per 100,000 population). Severe cases were significantly associated with younger age. Compared to patients ≥5 years of age, the odds ratios (ORs) for <1 year of age and 1 to <3 years of age were 5.74 (95% confidence interval [CI], 2.14–15.4) and 2.94 (95% CI, 1.02–8.51), respectively. Elevated ORs for hyperglycemia (plasma glucose level of ≥8.3 mmol/L) on admission (OR 3.60; 95% CI, 0.94–13.8) were also observed.

Conclusions: Disease burden of pediatric inpatients with HFMD, HA, and associated complications in Japan was described for the first time. During an EV71 epidemic, younger age and, suggestively, hyperglycemia may have been critical factors requiring more careful treatment.

Background: We sought to investigate the optimal values of BMI for the lowest risk of all-cause death and whether the optimal BMI differs according to smoking status in large-scale pooled analysis of 13 Japanese cohorts.

Methods: Data from 179,987 participants of 13 well-qualified cohort studies conducted throughout Japan were used for our analysis. A cohort-stratified Cox proportional hazard model was used. P values for interactions were calculated based on the cross product of BMI and age, sex, or smoking status.

Results: In the entire study population, all-cause mortality risk was lowest when the BMI was 22.0–24.9 kg/m². This was also the case for selected healthy participants (never smoked, baseline total cholesterol level ≥4.1 mmol/L; the first 5 years of follow-up data were excluded). No effect modification of age, sex, or smoking status was observed. Regardless of their BMI, never smokers always had a lower all-cause mortality risk than did current smokers even with an ideal BMI in terms of mortality risk.

Conclusion: A BMI of 22–24.9 kg/m² correlated with the lowest risk of mortality, regardless of whether all participants or selected healthy participants were analyzed. The fact that smoking was more strongly associated with mortality than obesity emphasizes the urgency for effective anti-smoking programs.

Background: Prolonged periods of sitting time can be adversely associated with older adults’ well-being and functional capacities. Understanding patterns and contexts of sedentary behaviors (SB) can inform approaches to prevention. This study examined Japanese older adults’ objectively-assessed patterns and reported domains of SB and their interrelationships.

Methods: Participants (n = 297; aged 65–84 years) of this cross-sectional study wore an accelerometer for 7 days and completed a survey. Five measures related to SB patterns were identified from the accelerometer data. SB from six domains, socio-demographics, and chronic conditions were identified from the survey data. Relative contributions of six domains to objectively-measured prolonged sedentary time (≥30 minutes) and the number of breaks were examined in a series of multivariate linear regressions. Covariates were socio-demographics, chronic conditions, and accelerometer wear time.

Results: On average, participants spent 8.8 hours a day sedentary (58% of accelerometer wear time), with 7.6 breaks per sedentary hour, and 3.7 hours a day through prolonged sedentary bouts (4.4 time/day). The proportions of time in the SB domains were 9.4% for car, 4.0% for public transport, 6.1% for work, 45.5% for television (TV) viewing, 9.8% for computer use, and 25.1% for other leisure. Domains of SB that contributed significantly to longer sedentary time through prolonged bouts were TV viewing and computer use. TV viewing was also associated with a lesser number of breaks.

Conclusions: For Japanese older adults, initiatives to address SB could focus on breaking-up prolonged periods of SB by encouraging more frequent breaks, especially during TV viewing.

Background: From around 2012, the use of automated equipment for fine particulate matter (PM_2.5) measurement with equivalence to a reference method has become popular nationwide in Japan. This enabled us to perform a national health effect assessment employing PM_2.5 concentrations based on the standardized measurement method. We evaluated the association between non-accidental mortality and short-term exposure to PM_2.5 and coarse particulate matter (PM), with the latter estimated as the difference between suspended particulate matter and PM_2.5, for the fiscal years 2012–2014.

Methods: This was a time-stratified case-crossover study in 100 highly-populated Japanese cities. Mortality data was obtained from the Ministry of Health, Labour and Welfare. City-specific estimates of PM-mortality association were calculated by applying a conditional logistic regression analysis, and combined with a random-effects meta-analysis.

Results: The respective averages of daily mean concentration were 14.6 µg/m³ for PM_2.5 and 6.4 µg/m³ for coarse PM. A 10 µg/m³ increase in PM_2.5 concentrations for the average of the day of death and the previous day was associated with an increase of 1.3% (95% confidence interval (CI), 0.9–1.6%) in total non-accidental mortality. For cause-specific mortality, PM_2.5 was positively associated with cardiovascular and respiratory mortality. After adjustment for PM_2.5, we observed a 1.4% (95% CI, 0.2–2.6%) increase in total mortality with a 10 µg/m³ increase in coarse PM.

Conclusion: The study revealed that short-term exposure to PM_2.5 had adverse effects on total non-accidental, cardiovascular, and respiratory mortality in Japan. Coarse PM exposure also increased the risk of total mortality.

Background: While bathing styles vary among countries, most Japanese people prefer tub bathing to showers and saunas. However, few studies have examined the relationship between tub bathing and health outcomes. Accordingly, in this prospective cohort study, we investigated the association between tub bathing frequency and the onset of functional disability among older people in Japan.

Methods: We used data from the Japan Gerontological Evaluation Study (JAGES). The baseline survey was conducted from August 2010 through January 2012 and enrolled 13,786 community-dwelling older people (6,482 men and 7,304 women) independent in activities of daily living. During a 3-year observation period, the onset of functional disability, identified by new certification for need of Long-Term Care Insurance, was recorded. Tub bathing frequencies in summer and winter at baseline were divided into three groups: low frequency (0–2 times/week), moderate frequency (3–6 times/week), and high frequency (≥7 times/week). We estimated the risks of functional disability in each group using a multivariate Cox proportional hazards model.

Results: Functional disability was observed in a total of 1,203 cases (8.7%). Compared with the low-frequency group and after adjustment for 14 potential confounders, the hazard ratios of the moderate- and high-frequency groups were 0.91 (95% confidence interval [CI], 0.75–1.10) and 0.72 (95% CI, 0.60–0.85) for summer and 0.90 (95% CI, 0.76–1.07) and 0.71 (95% CI, 0.60–0.84) for winter.

Conclusion: High tub bathing frequency is associated with lower onset of functional disability. Therefore, tub bathing might be beneficial for older people’s health.

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.

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.

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.

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 2,222 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 for screen time <0.5, ≥0.5 to <1, and ≥1 h/d were 1.0 (reference), 3.81 (95% confidence interval, 1.04–13.98), and 4.36 (95% confidence interval, 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.

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.

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.

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.

Background: Although the majority of survivors of the huge Great East Japan 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 via K6 score were the dependent variables, and social participation was the independent variable. Odds ratios of the social participation on health variables were estimated using 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 19,726 and 28,270, respectively. Participants in prefabricated housing had poorer SRH and K6 than those in rented housing. The proportions of participants engaging in 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.

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.

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.

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.

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.

Objective: Colorectal cancer (CRC) is the 4^th 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.

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 years. 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 ratios (ORs) for IADL decline with 95% confidence intervals (CIs) 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 (OR 1.53; 95% CI, 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 (OR 1.37; 95% CI, 1.03–1.84). Among women, none of the working history items were 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 men retain IADL in later life.

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.

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.

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.

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 5-year age groups and LTC needs level.

Results: The study analyzed 12,852 men and 18,020 women, among which 13.3% and 41.5%, respectively, were 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 [IRR] 0.90; 95% confidence interval [CI], 0.87–0.92 for men and IRR 0.97; 95% CI, 0.95–0.99 for women), longer LOS (IRR 1.98; 95% CI, 1.54–2.56 and IRR 1.42; 95% CI, 1.20–1.67, respectively), and higher total expenditures (exp(β) 1.09; 95% CI, 1.01–1.18 and exp(β) 1.09; 95% CI, 1.05–1.14, respectively).

Conclusions: This study suggests that 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.

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.

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.

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.

Background: It is unclear whether either neighborhood collective efficacy or school collective efficacy is 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 as current alcohol drinking, which was defined as self-reported drinking on at least 1 day in the past 30 days. Collective efficacy was measured using scales of social cohesion and informal social control in school and the neighborhood. Contextual-level collective efficacy was measured using 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 was 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 and OR 0.61; 95% CI, 0.49–0.75, respectively), whereas neighborhood collective efficacy at individual- and contextual-levels was not associated with alcohol consumption.

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