Journal of Epidemiology
Online ISSN : 1349-9092
Print ISSN : 0917-5040
ISSN-L : 0917-5040
Volume 25 , Issue 2
Showing 1-13 articles out of 13 articles from the selected issue
Review Article
  • Pietro Amedeo Modesti, Eleonora Perruolo, Gianfranco Parati
    2015 Volume 25 Issue 2 Pages 91-98
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: November 22, 2014
    Hypertension is now the foremost cause of disability and is responsible for the highest percentage of attributable death among risk factors. These global changes are mainly due to the increase in the prevalence of hypertension in most low- and middle-income countries (LMICs) as a consequence of relevant socioeconomic changes occurring during the last decades. Implementation of global prevention efforts urgently needs to be accelerated because of the increasing incidence of haemorrhagic stroke, renal failure, and hypertensive heart disease in developing countries. Blood pressure (BP) measurement has different implications in epidemiological studies performed in low-resource settings. First, the frequency of blood pressure measurement is a simple but reliable indicator of access to healthcare in epidemiological studies, which may disclose the favourable effects of urbanization; the opportunity to have BP measured increases hypertension awareness, facilitates drug treatment, and leads to better achievement of BP control. Second, BP measurement is a key element in cardiovascular risk stratification, focusing solely on the preferred strategy in low-resource settings where costs of biochemical tests might be less sustainable. Third, the issue of obtaining reliable estimation of BP values is crucial to achieve sound data on the burden of hypertension in LMICs, and some aspects of BP measurement, such as the use of reliable automated devices, the number of measurements/visits to achieve a consistent diagnosis of hypertension, and the possible confounding effect of environmental factors, must be closely considered.
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Original Article
  • Esayas Haregot Hilawe, Hiroshi Yatsuya, Yuanying Li, Mayu Uemura, Chao ...
    2015 Volume 25 Issue 2 Pages 99-109
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: November 15, 2014
    Background: Although the association between cigarette smoking and risk of type 2 diabetes is well established, its mechanisms are yet to be clarified. This study examined the possible mediating effects of adiponectin, leptin, and C-reactive protein (CRP) concentrations on the smoking-diabetes association.
    Methods: Between 2002 and 2011, we followed 3338 Japanese workers, aged 35–66 years, who were enrolled in the second Aichi workers’ cohort study. We used multivariable-adjusted Cox regression models to determine the hazard ratios and respective 95% confidence intervals (CIs) of the association between smoking status and risk of diabetes. A multiple mediation model with bootstrapping was used to estimate the magnitude and the respective bias-corrected (BC) 95% CIs of the indirect effects of smoking on diabetes through the three biomarkers.
    Results: Relative to never smokers, the risk of diabetes was significantly elevated in current (hazard ratio 1.75, 95% CI 1.25–2.46) and ex-smokers (hazard ratio 1.54, 95% CI 1.07–2.22). The indirect effects of smoking on diabetes through adiponectin levels were statistically significant among light (point estimate 0.033, BC 95% CI 0.005–0.082), moderate (point estimate 0.044, BC 95% CI 0.010–0.094), and heavy smokers (point estimate 0.054, BC 95% CI 0.013–0.113). In contrast, neither the indirect effects of smoking on diabetes through leptin nor CRP levels were significant, as the corresponding BC 95% CIs included zero.
    Conclusions: In our analysis, adiponectin concentration appeared to partially mediate the effect of smoking on diabetes, while leptin and CRP levels did not.
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  • Koichi Fukumoto, Tetsuo Taniguchi, Noriyasu Usami, Koji Kawaguchi, Tak ...
    2015 Volume 25 Issue 2 Pages 110-116
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: December 06, 2014
    Background: The ABO blood group is reported to be associated with the incidence and patient survival for several types of malignancies. We conducted a retrospective study to evaluate the prognostic significance of the ABO blood group in patients with resected non-small cell lung cancer (NSCLC).
    Methods: A total of 333 patients (218 men and 115 women) with resected NSCLC were included in this study. In addition to age, sex, smoking status, preoperative serum carcinoembryonic antigen (CEA) level, operative procedure, histology of tumors, pathological stage (p-stage), and adjuvant therapy, the association between the ABO blood group and survival was explored.
    Results: The 5-year overall and disease-free survival rates were 83.0% and 71.6% for blood group O, 67.2% and 62.3% for blood group A, 68.8% and 68.8% for blood group B and 69.2% and 65.3% for blood group AB, respectively. A multivariate analysis for overall survival showed the ABO blood group (group A vs. group O: HR 2.47, group AB vs. group O: HR 3.62) to be an independent significant prognostic factor, in addition to age, sex, smoking status, p-stage, and serum CEA level. A multivariate analysis for disease-free survival also showed the ABO blood group to be an independent significant prognostic factor.
    Conclusions: The ABO blood group is an independent prognostic factor in patients with resected NSCLC. Studies of other larger cohorts are therefore needed to confirm the relationship between the ABO blood group and the prognosis among patients with resected NSCLC.
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  • Megumi Hara, Chisato Shimanoe, Yasuko Otsuka, Yuichiro Nishida, Hinako ...
    2015 Volume 25 Issue 2 Pages 117-125
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: November 15, 2014
    Background: Non-participation in second surveys is reported to be associated with certain baseline characteristics; however, such data are unavailable for Japanese populations. Although disease incidence during follow-up might influence participation, few reports have addressed this possibility. This study sought to identify factors associated with non-participation in a second survey of a population-based cohort, and to evaluate the influence of self-reported disease incidence on non-participation.
    Methods: After excluding participants who left the area (n = 423), died (n = 163), and withdrew from the study (n = 9) among 12 078 participants in a baseline survey for the Japan Multi-Institutional Collaborative Cohort Study in the Saga region between 2005 and 2007, 11 483 people were invited by mail to participate in a face-to-face second survey between 2010 and 2012. The 5-year clinical health history of non-participants was assessed by mail or telephone. Baseline characteristics and self-reported clinical outcomes of non-participants were compared with those of participants.
    Results: Among 11 483 people, 8454 (73.6%) participated in the second survey, and 2608 out of 3029 non-participants answered mail or telephone health surveys. Female sex, youngest and oldest ages, lower education, lower occupational class, current smoking, lower physical activity level, shorter sleep time, obesity, and constipation were associated with non-participation. Light drinking (0.1–22.9 g ethanol/day) was associated with participation. Non-participants reported a significantly higher incidence of cancer and a significantly lower proportion of hypertension compared with participants.
    Conclusions: Both baseline characteristics and disease incidence during the follow-up period had significant associations with non-participation in the face-to-face second survey.
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  • Hideto Suzuki, Wakako Hikiji, Takanobu Tanifuji, Nobuyuki Abe, Tatsush ...
    2015 Volume 25 Issue 2 Pages 126-132
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: December 13, 2014
    Background: Sudden bath-related deaths occur frequently in Japan, particularly among elderly people. However, the precise mechanism of bath-related death remains uncertain, and effective prevention strategies have not been established.
    Methods: Cases of bath-related deaths (n = 3289) were selected from all cases handled by the Tokyo Medical Examiner’s Office from 2009 to 2011 (N = 41 336). The ages and occurrence dates were examined, and major autopsy findings, including toxicological analysis, were evaluated for the autopsied cases (n = 550).
    Results: Most cases occurred in individuals older than 60 years of age during winter. Analysis of autopsy findings revealed water inhalation signs in many cases (n = 435, 79.1%). Circulatory system diseases constituted more than half of the pathological findings regarding factors that may have contributed significantly to death (n = 300, 54.5%), and cardiac lesions were the most common pathological finding (n = 250, 45.5%). However, approximately one-third of the cases exhibited no remarkable pathological findings (n = 198, 36.0%). A quarter of all cases involved blood ethanol levels that exceeded 0.5 mg/mL (n = 140).
    Conclusions: The results suggested that drowning plays an important role in the final process of bath-related death. Circulatory system diseases may be the primary underlying pathology; however, there were variations in the medical histories and pathologies of cases of bath-related death. From a preventive perspective, family members should pay attention to elderly people with circulatory system diseases during bathing, particularly in winter. Additionally, the notion that ill or inebriated individuals should not take baths should be reinforced.
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  • Jean-Baptiste Beuscart, Dominique Pagniez, Eric Boulanger, Alain Duham ...
    2015 Volume 25 Issue 2 Pages 133-141
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: December 20, 2014
    Background: Access to the renal transplantation (RT) waiting list depends on factors related to lower mortality rates and often occurs after dialysis initiation. The aim of the study was to use a flexible regression model to determine if registration on the RT waiting list is associated with mortality on dialysis, independent of the comorbidities associated with such registration.
    Methods: Data from the French REIN registry on 7138 incident hemodialysis (HD) patients were analyzed. A multi-state model including four states (‘HD, not wait-listed’, ‘HD, wait-listed’, ‘death’, and ‘RT’) was used to estimate the effect of being wait-listed on the probability of death.
    Results: During the study, 1392 (19.5%) patients were wait-listed. Of the 2954 deaths observed in the entire cohort during follow-up, 2921 (98.9%) were observed in the not wait-listed group compared with only 33 (1.1%) in the wait-listed group. In the multivariable analysis, the adjusted hazard ratio for death associated with non-registration on the waiting list was 3.52 (95% CI, 1.70–7.30). The risk factors for death identified for not wait-listed patients were not found to be significant risk factors for wait-listed patients, with the exception of age.
    Conclusions: The use of a multi-state model allowed a flexible analysis of mortality on dialysis. Patients who were not wait-listed had a much higher risk of death, regardless of co-morbidities associated with being wait-listed, and did not share the same risk factors of death as wait-listed patients. Registration on the waiting list should therefore be taken into account in survival analysis of patients on dialysis.
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  • Yoshimi Nakayama, Mitsuru Mori
    2015 Volume 25 Issue 2 Pages 142-147
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: January 10, 2015
    Background: Early childhood caries (ECC) is one of the most prevalent chronic diseases among children. The aim of this cross-sectional study was to investigate the association between nocturnal breastfeeding, snacking habits, or other risk factors and ECC in 18- to 23-month-old Japanese children.
    Methods: Study subjects were 1675 children aged 18 to 23 months. A self-administered questionnaire was completed by parents or guardians of the children. The survey contents included such things as number of decayed, missing, and filled teeth per child, smokers in the home, nocturnal breastfeeding habit, snack times, kinds of snacks consumed ≥4 days a week, kinds of drinks consumed ≥4 days a week, parents brushing their child’s teeth daily, and the use of fluoride toothpaste. Logistic regression analysis was performed to estimate the odds of ECC.
    Results: The average number of decayed, missing and filled teeth was 0.10. The prevalence of dental caries was 3.3%. Nocturnal breastfeeding habits were reported in 357 subjects (21.3%). After excluding items of multicollinearity, significant associations were observed between ECC and nocturnal breastfeeding, drinking or eating sweets after dinner every day, and the intake of candy, soda and/or isotonic drinks ≥4 days a week.
    Conclusions: This study suggests that nocturnal breastfeeding and snacking habits are correlated with ECC.
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  • Salvador Pita-Fernández, Cristina González-Martín ...
    2015 Volume 25 Issue 2 Pages 148-154
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: November 08, 2014
    Background: Research is needed to determine the prevalence and variables associated with the diagnosis of flatfoot, and to evaluate the validity of three footprint analysis methods for diagnosing flatfoot, using clinical diagnosis as a benchmark.
    Methods: We conducted a cross-sectional study of a population-based random sample ≥40 years old (n = 1002) in A Coruña, Spain. Anthropometric variables, Charlson’s comorbidity score, and podiatric examination (including measurement of Clarke’s angle, the Chippaux-Smirak index, and the Staheli index) were used for comparison with a clinical diagnosis method using a podoscope. Multivariate regression was performed. Informed patient consent and ethical review approval were obtained.
    Results: Prevalence of flatfoot in the left and right footprint, measured using the podoscope, was 19.0% and 18.9%, respectively. Variables independently associated with flatfoot diagnosis were age (OR 1.07), female gender (OR 3.55) and BMI (OR 1.39). The area under the receiver operating characteristic curve (AUC) showed that Clarke’s angle is highly accurate in predicting flatfoot (AUC 0.94), followed by the Chippaux-Smirak (AUC 0.83) and Staheli (AUC 0.80) indices. Sensitivity values were 89.8% for Clarke’s angle, 94.2% for the Chippaux-Smirak index, and 81.8% for the Staheli index, with respective positive likelihood ratios or 9.7, 2.1, and 2.0.
    Conclusions: Age, gender, and BMI were associated with a flatfoot diagnosis. The indices studied are suitable for diagnosing flatfoot in adults, especially Clarke’s angle, which is highly accurate for flatfoot diagnosis in this population.
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  • Qiguo Lian, Xiayun Zuo, Chaohua Lou, Ersheng Gao, Yan Cheng
    2015 Volume 25 Issue 2 Pages 155-161
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: November 29, 2014
    Purpose: Despite robust empirical and theoretical evidence for higher rates of suicide among lesbian, gay, and bisexual (LGB) youths, little is known about the relationship between suicide and sexual orientation among Asian youths. This study examined differences in prevalence of suicidal ideation and suicide attempts between LGB and heterosexual youths in the cities of Hanoi, Shanghai, and Taipei, China.
    Methods: The data are from a community-based multi-centre cross-sectional study conducted from 2006 to 2007, with a sample of 17 016 youths aged 15–24 years from Hanoi, Shanghai, and Taipei. Chi-square test and logistic regression were used to evaluate correlates of suicidal ideation and suicide attempts.
    Results: The overall prevalence of suicidal ideation and suicide attempts in the preceding 12 months in LGB youths were both higher than in heterosexual youth (12.8% vs. 8.1% and 4.0% vs. 2.4%, respectively). Stratified by city, the prevalence of suicidal ideation was lowest in Hanoi (2.2%), followed by Shanghai (8.0%) and Taipei (17.0%). Similar trends were observed in the prevalence of suicide attempts, which was lowest in Hanoi (0.3%), followed by Shanghai (1.2%) and Taipei (2.5%). Of note, however, multivariate logistic regression results revealed that LGB youth were at a higher risk for suicidal ideation than heterosexual youth only in Taipei (odds ratio 1.65).
    Conclusions: Suicidality is common among Asian youth, with higher prevalence observed in urbanized cities. LGB youths are at greater risk of suicidal ideation than their heterosexual counterparts in Taipei than in the other two examined cities.
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  • Miwako Tsunematsu, Masayuki Kakehashi
    2015 Volume 25 Issue 2 Pages 162-171
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: December 06, 2014
    Background: Although the United States Preventive Services Task Force (USPSTF) downgraded their recommendation for breast cancer screening for women aged 40–49 years in 2009, Japanese women in their 40s have been encouraged to attend breast cancer screenings since 2004. The aim of this study is to examine whether these different mass-screening strategies are justifiable by the different situations of these countries and to provide evidence for suitable judgment.
    Methods: Performance of screening strategies (annual/biennial intervals; initiating/terminating ages) was evaluated using a mathematical model based on the natural history of breast cancer and the transition between its stages. Benefits (reduced number of deaths and extended average life expectancy) and harm (false-positives) associated with these strategies were calculated.
    Results: Additional average life expectancy by including women in their 40s as participants were 13 days (26%) and 25 days (22%) in Japan and the United States, respectively, under the biennial screening condition; however, the respective increases in numbers of false-positive cases were 65% and 53% in Japan and the United States. Moreover, the number of screenings needed to detect one diagnosis or to avert one death was smaller when participants were limited to women of age 50 or over than when women in their 40s were included. The validity of including women in their 40s in Japan could not be determined without specifying the weight of harms compared to benefits.
    Conclusions: Whether screening of women in their 40s in Japan is justifiable must be carefully determined based the quantitative balance of benefits and harms.
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  • Ching-Piao Tsai, Feng-Cheng Lin, Johnny Kuang-Wu Lee, Charles Tzu-Chi ...
    2015 Volume 25 Issue 2 Pages 172-177
    Published: February 05, 2015
    Released: February 05, 2015
    [Advance publication] Released: December 27, 2014
    Background: The association of aspirin use and nonsteroid anti-inflammatory drug (NSAID) use with amyotrophic lateral sclerosis (ALS) risk is unclear. This study determined whether use of any individual compound is associated with ALS risk by conducting a total population-based case-control study in Taiwan.
    Methods: A total of 729 patients with newly diagnosed ALS who had a severely disabling disease certificate between January 1, 2002, and December 1, 2008, comprised the case group. These cases were compared with 7290 sex-, age-, residence-, and insurance premium-matched controls. Drug use by each Anatomical Therapeutic Chemical code was analyzed using conditional logistic regression models. False discovery rate (FDR)-adjusted P values were reported in order to avoid inflating false positives.
    Results: Of the 1336 compounds, only the 266 with use cases exceeding 30 in our database were included in the screening analysis. Without controlling for steroid use, the analysis failed to reveal any compound that was inversely associated with ALS risk according to FDR criteria. After controlling for steroid use, we found use of the following compounds to be associated with ALS risk: aspirin, diphenhydramine (one of the antihistamines), and mefenamic acid (one of the NSAIDs). A multivariate analysis revealed that aspirin was independently inversely associated with ALS risk after controlling for diphenhydramine, mefenamic acid, and steroid use. The inverse association between aspirin and ALS was present predominately in patients older than 55 years.
    Conclusions: The results of this study suggested that aspirin use might reduce the risk of ALS, and the benefit might be more prominent for older people.
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