Background: Globally, few published studies have tracked the temporal trend of dioxin levels in the human body since 2000. This study describes the annual trend of dioxin levels in human breast milk in Japanese mothers from 1998 through 2015.
Methods: An observational study was conducted from 1998 through 2015. Participants were 1,194 healthy mothers following their first delivery who were recruited annually in Japan. Breast milk samples obtained from participants were analyzed using gas chromatography and mass spectrometry for dioxins, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs).
Results: Mean age was 29.5 years, and 53% of participants were 20–25 years old. A declining trend in total dioxin levels was found, from a peak of 20.8 pg toxic equivalence (TEQ)/g fat in 1998 to 7.2 pg TEQ/g fat in 2014. Data from the last 5 years of the study indicated a plateau at minimal levels. In contrast, an increasing trend was found in the mean age of participants during the last 5 years. Although significantly higher dioxin levels were observed in samples from older participants, an upward trend in dioxin levels was not observed, indicating that dietary and environmental exposure to dioxins had greatly diminished in recent years.
Conclusions: Dioxin levels in human breast milk may be approaching a minimum in recent years in Japan. The findings may contribute to global reference levels for environmental pollution of dioxins, which remains a problem for many developing countries.
Background: This study aimed to explore the associations between weight status, physical activity, and depression in Korean older adults.
Methods: We used the baseline data drawn from the 2008 baseline survey utilized in the Living Profiles of Older People Survey, comprised of 15,146 community-dwelling older people (42.6% men and 57.4% women) aged 60 years and older residing in the Republic of Korea. After excluding respondents with missing data on height, weight, and physical activity (PA), data on 10,197 samples (43.3% men and 56.7% women) were analyzed in this study.
Results: Underweight and completely inactive individuals had poorer sociodemographic and health behavioral characteristics and increased risks of late-life depression compared with normal weight and sufficiently active individuals, respectively. In terms of the aerobic PA guidelines, completely inactive individuals had a significantly higher risk of late-life depression (odds ratio 1.730; 95% confidence interval, 1.412–2.120) compared with sufficiently active individuals, even after adjustments for age, education, household income, night sleeping, living status, marital status, smoking, number of comorbidities, nutritional status, self-reported health status, and cognitive performance as covariates. In addition, those who did not meet the PA guidelines and were underweight or overweight/obese were more likely to have late-life depression compared to those who were active and normal weight.
Conclusions: The current findings of the study suggest that modifiable, lifestyle risk factors, such as physical inactivity, underweight, and overweight/obesity, are positively associated with late-life depression in Korean older adults.
Background: The body mass index (BMI) of preschool children from 4 years of age through primary school has increased since the Great East Japan Earthquake, but that of children aged under 3 years has not been studied. This study evaluated how the anthropometrics of younger children changed following the earthquake.
Methods: Height and weight data of children living in northeast Japan were collected from 3-, 6-, 18-, and 42-month child health examinations. We compared the changes in BMI, weight, and height among infants affected by the earthquake between their 3- and 6-month health examinations, toddlers affected at 21–30 months of age (affected groups), and children who experienced the earthquake after their 42-month child health examination (unaffected group). A multilevel model was used to calculate the BMI at corresponding ages and to adjust for the actual age at the 3-month health examination, health examination interval, and gestational age.
Results: We recruited 8,479 boys and 8,218 girls living in Fukushima, Miyagi, and Iwate Prefectures. In the infants affected between their 3- and 6-month health examinations in Fukushima, the change in BMI at 42 months of age was greater than among the unaffected children. In the toddlers affected at 21–30 months of age in Fukushima, the change in BMI was greater, but changes in weight and height were less.
Conclusions: Affected infants and toddlers in Fukushima suggested some growth disturbances and early adiposity rebound, which can cause obesity. The future growth of children affected by disasters should be followed carefully.
Background: The conventional concept of positive association between general obesity and bone health was challenged in recent studies reporting the different effects of specific fat deposition on bone health. In the present study, we investigated the association between epicardial fat and bone health.
Methods: We measured echocardiographic epicardial fat thickness (EFT) and bone mineral content (BMC) in a twin-family cohort of Koreans (n = 1,198; 525 men, 460 pre- and 213 post-menopausal women). A total 121 pairs of monozygotic twin (MZ) and 404 pairs of dizygotic twin and sibling pairs (DZ/Sib) were included.
Results: EFT was positively associated with BMC in total, as well as in three subgroups (β = 0.107, 0.076, and 0.058 for men, pre-, and post-menopausal women, respectively). The positive association between EFT and BMC remained for DZ/Sib difference analysis, but was absent for MZ comparisons. The positive association between BMI and BMC was consistent for DZ/Sib and MZ difference analysis. After adjusting for the effect of general obesity via BMI, the association between BMC and EFT was statistically non-significant (β = 0.020, 0.000, and −0.009 for men, pre-, and post-menopausal women, respectively).
Conclusion: Our findings do not support epicardial fat’s beneficial effects on bone health, whereas general adiposity has an osteotropic effect. The association between EFT and BMC is through common genetic component factors.
Background: Yellow tongue coating is one of the clinical signs for diabetes mellitus according to traditional East Asian medicine. Few reports have been available on the association between yellow tongue coating and the prevalence of type 2 diabetes in the general population. We examined that association among population samples of non-smoking men and women.
Methods: The study subjects were Japanese non-smoking men (n = 315) and women (n = 654) aged 30–79 years who resided in Toon city and participated in the Toon Health Study from July 2011 through November 2014. Tongue coating was assessed by a nationally licensed acupuncturist and classified into three categories of white (normal), light yellow, and yellow. We performed an oral glucose tolerance test to confirm the presence of diabetes mellitus and prediabetes. The associations between yellow tongue coating and the prevalence of diabetes mellitus and prediabetes were examined using multivariable logistic regression analyses, adjusting for age, sex, body mass index, drinking status, and physical activity.
Results: The multivariable odds ratios of diabetes mellitus were 1.39 (95% confidence interval [CI], 0.72–2.67) for light yellow tongue coating and 2.23 (95% CI, 1.16–4.30) for yellow tongue coating compared with white tongue coating. The respective multivariable odds ratios of prediabetes were 1.13 (95% CI, 0.80–1.61) and 1.43 (95% CI, 0.96–2.12).
Conclusions: Yellow tongue coating was associated with higher prevalence of diabetes mellitus and tended to be associated with that of prediabetes among Japanese non-smoking men and women.
A mathematical model of the transmission dynamics of infectious disease is an important theoretical epidemiology method, which has been used to simulate the prevalence of hepatitis B and evaluate different immunization strategies. However, differences lie in the mathematical processes of modeling HBV transmission in published studies, not only in the model structure, but also in the estimation of certain parameters. This review reveals that the dynamics model of HBV transmission only simulates the spread of HBV in the population from the macroscopic point of view and highlights several main shortcomings in the model structure and parameter estimation. First, age-dependence is the most important characteristic in the transmission of HBV, but an age-structure model and related age-dependent parameters were not adopted in some of the compartmental models describing HBV transmission. In addition, the numerical estimation of the force of HBV infection did not give sufficient weight to the age and time factors and is not suitable using the incidence data. Lastly, the current mathematical models did not well reflect the details of the factors of HBV transmission, such as migration from high or intermediate HBV endemic areas to low endemic areas and the kind of HBV genotype. All of these shortcomings may lead to unreliable results. When the mathematical model closely reflects the fact of hepatitis B spread, the results of the model fit will provide valuable information for controlling the transmission of hepatitis B.
Background: A high body mass index (BMI) has been proposed as an important risk factor for pancreatic cancer. However, this association of BMI with pancreatic cancer risk has not been confirmed in Asian populations.
Methods: We evaluated the association between BMI (either at baseline or during early adulthood) and pancreatic cancer risk by conducting a pooled analysis of nine population-based prospective cohort studies in Japan with more than 340,000 subjects. Summary hazard ratios (HRs) were estimated by pooling study-specific HRs for unified BMI categories with a random-effects model.
Results: Among Japanese men, being obese at baseline was associated with a higher risk of pancreatic cancer incidence (≥30 kg/m2 compared with 23 to <25 kg/m2, adjusted HR 1.71; 95% confidence interval [CI], 1.03–2.86). A J-shaped association between BMI during early adulthood and pancreatic cancer incidence was seen in men. In contrast, we observed no clear association among women, although there may be a positive linear association between BMI at baseline and the risk of pancreatic cancer (per 1 kg/m2, adjusted HR 1.02; 95% CI, 1.00–1.05).
Conclusions: Pooling of data from cohort studies with a considerable number of Japanese subjects revealed a significant positive association between obesity and pancreatic cancer risk among men. This information indicates that strategies that effectively prevent obesity among men might lead to a reduced burden of pancreatic cancer, especially in Asian populations.
Background: We sought to examine the association between cardiorespiratory fitness (CRF) and incidence of type 2 diabetes considering the follow-up period in a cohort of Japanese men with a maximum follow-up period of 23 years.
Methods: This study enrolled 7,804 male workers free of diabetes in 1986. CRF was measured using a cycle ergometer, and maximal oxygen uptake was estimated. During 1986–2009, participants were followed for development of type 2 diabetes, which was diagnosed using fasting blood tests, self-administered questionnaires, or oral glucose tolerance tests after urinary tests from annual health checkups. Hazard ratios for the incidence of type 2 diabetes were estimated using Cox proportional hazards models.
Results: During the follow-up period, 1,047 men developed type 2 diabetes. In analyses by follow-up periods (1986–1993, 1994–2001, and 2002–2009), there was an inverse dose-response relationship between CRF and the development of type 2 diabetes for all three follow-up periods (P for trend 0.019, <0.001, and 0.001, respectively), and the association between CRF at baseline and the incidence of type 2 diabetes did not weaken with longer follow-up period. Compared with the lowest CRF group, hazard ratios of developing type 2 diabetes were 0.69 (95% confidence interval [CI], 0.49–0.97) for the highest CRF group in 1986–1993, 0.57 (95% CI, 0.42–0.79) for the highest CRF in 1994–2001, and 0.47 (95% CI, 0.30–0.74) for the highest CRF in 2002–2009.
Conclusion: High CRF is associated with a lower risk of the incidence of type 2 diabetes over an extended period of >20 years among men.
Background: Although beneficial associations have been reported between moderate alcohol intake and the serum lipid profile, it is unclear whether polymorphisms in alcohol-metabolizing enzymes can modify these associations. Here, we assessed the effects of ADH1B His48Arg (rs1229984), ALDH2 Glu504Lys (rs671), and their combination on these associations. Furthermore, we examined if the findings for ALDH2 could be replicated.
Methods: We categorized 889 male participants in the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study into two groups based on presence or absence of minor allele(s) or four groups based on genotype combinations. We performed regression analyses of serum lipid concentrations on alcohol intake, with multivariable adjustment. The replication study was conducted among 2,562 men in the Shizuoka part of the J-MICC Study.
Results: The ALDH2 Glu/Lys or Lys/Lys groups showed significant decreases in serum low-density lipoprotein (LDL) cholesterol with increasing alcohol consumption; the coefficient per intake increase of 10 g/day was −2.49 mg/dL (95% confidence interval [CI], −3.85 to −1.13), and a significant interaction with the polymorphism was confirmed (P for interaction = 0.006). This inverse correlation was more evident among the ADH1B His/His + ALDH2 Glu/Lys or Lys/Lys groups (−3.24 mg/dL, 95% CI, −5.03 to −1.45). Serum triglycerides were positively associated with alcohol consumption in the ADH1B His/His group (P for interaction = 0.020). The stronger association between serum LDL cholesterol and alcohol consumption in the ALDH2 Glu/Lys or Lys/Lys groups was replicated.
Conclusions: The ALDH2 Glu504Lys polymorphism can modify the association between alcohol intake and serum LDL cholesterol in Japanese men.
Background: The “Physical Activity Reference for Health Promotion 2013” provides “fit” reference values for cardiorespiratory fitness (CRF) for good health. The importance of achieving a fit CRF level for several years on the subsequent prevention of type 2 diabetes mellitus (T2DM) remains to be clarified.
Methods: This cohort study was conducted in 2,235 nondiabetic males aged 21 to 59 years, enrolled in April 1986 through March 1987. We calculated the ratio of the area under the curve (AUCratio) for actual measured values and the AUC for the reference values of CRF in each individual during an 8-year measurement period before the baseline. According to whether they met a fit CRF level or not, participants were categorized into groups based on the AUCratio (FitAUC or UnfitAUC) and initial CRF (Fitinitial or Unfitinitial), respectively. T2DM was evaluated on health checkups until March 2010.
Results: During the follow-up period, 400 men developed T2DM. After adjustment for confounders, as compared with those in the FitAUC group, the hazard ratio (HR) for those in the UnfitAUC group was 1.33 (95% confidence interval [CI], 1.06–1.65). A combined analysis with the categories of initial value and AUCratio showed that, compared with the Fitinitial and FitAUC group, the HRs of Fitinitial and UnfitAUC, Unfitinitial and FitAUC, and Unfitinitial and UnfitAUC groups were 1.41 (95% CI, 0.99–2.00), 1.18 (95% CI, 0.81–1.70), and 1.40 (95% CI, 1.08–1.83), respectively.
Conclusion: Achievement of a fit CRF level established in the Japan physical activity guideline for several years was associated with lower subsequent risk of T2DM.
Background: This retrospective cohort study primarily aimed to investigate the possible association of computer use with visual field abnormalities (VFA) among Japanese workers.
Methods: The study included 2,377 workers (mean age 45.7 [standard deviation, 8.3] years; 2,229 men and 148 women) who initially exhibited no VFA during frequency doubling technology perimetry (FDT) testing. Subjects then underwent annual follow-up FDT testing for 7 years, and VFA were determined using a FDT-test protocol (FDT-VFA). Subjects with FDT-VFA were examined by ophthalmologists. Baseline data about the mean duration of computer use during a 5-year period and refractive errors were obtained via self-administered questionnaire and evaluations for refractive errors (use of eyeglasses or contact lenses), respectively.
Results: A Cox proportional hazard analysis demonstrated that heavy computer users (>8 hr/day) had a significantly increased risk of FDT-VFA (hazard ratio [HR] 2.85; 95% confidence interval [CI], 1.26–6.48) relative to light users (<4 hr/day), and this association was strengthened among subjects with refractive errors (HR 4.48; 95% CI, 1.87–10.74). The computer usage history also significantly correlated with FDT-VFA among subject with refractive errors (P < 0.05), and 73.1% of subjects with FDT-VFA and refractive errors were diagnosed with glaucoma or ocular hypertension.
Conclusions: The incidence of FDT-VFA appears to be increased among Japanese workers who are heavy computer users, particularly if they have refractive errors. Further investigations of epidemiology and causality are warranted.
Background: The purpose of this cross-sectional study was to describe the patterns and levels of sedentary time and physical activity (PA) in a general Japanese population.
Methods: A total of 1,740 community-dwelling Japanese adults aged ≥40 years participated in this study. Sedentary time and PA were assessed for 7 consecutive days using a tri-axial accelerometer. Daily patterns and levels of sedentary time and PA were calculated by sex, age group (40–64, 65–74, and ≥75 years), and body mass index (BMI; <25 and ≥25 kg/m2).
Results: Participants spent half of their waking time being sedentary, 32.7% of which was accumulated in prolonged bouts ≥30 minutes, versus only 54.4 minutes/day (7% of waking time) as moderate-to-vigorous PA (MVPA) (11.8 minutes/day in bouts ≥10 minutes). In addition to total sedentary time, men had longer prolonged sedentary bouts and fewer breaks per sedentary hour than women. Similar trends were observed in participants aged ≥75 years and those with a higher BMI (≥25 kg/m2) compared to those with a younger age and lower BMI. Moreover, participants aged ≥75 years and those with a higher BMI accumulated fewer MVPA minutes in bouts ≥10 minutes. Only 34.8% of the population met the recommended level of ≥150 minutes/week MVPA in bouts ≥10 minutes.
Conclusion: Japanese adults accumulated a large proportion of total sedentary time in prolonged bouts but few minutes in sustained bouts of MVPA, and few of them met the current PA guideline.
Background: Dizziness is one of the most common complaints in medicine and a frequent symptom among older people. Dizziness has a considerable impact on life quality and is associated with high economic costs. The purpose of this study was to evaluate the prevalence of dizziness in the general population and to describe its clinical characteristics and associated factors.
Methods: The Korea National Health and Nutrition Examination Survey (KNHANES) is a cross-sectional survey of the civilian, non-institutionalized population of South Korea. We evaluated data for 12,653 participants (5,450 men and 7,203 women), aged 40 years and above, whom participated in the KNHANES between 2010 and 2012.
Results: In the age group over 40 years old, the 1-year prevalence of dizziness was 20.10%. Dizziness was more prevalent among women (25.18%) than among men (14.57%; P < 0.001) and the prevalence rate increased with age (P < 0.001). In multivariable analysis, female sex, older age, serum triglyceride level, experience of depression, limited functional status owing to visual acuity impairment, limited physical performance, smoking, alcohol consumption, and perception of stress were independently associated with dizziness.
Conclusions: In our study, the prevalence of dizziness in the general population was 20.10%. There was a stronger relationship between dizziness and physical performance, chronic diseases, and health behaviors compared to that with otologic diseases. Interventions for dizziness should be approached in a multifactorial manner and an understanding of various factors is necessary for the prevention and management of this condition.
Background: The prevalence of Internet addiction (IA) among employed adults has not been reported using a large sample. To clarify the actual status of addictive Internet use among employed adults, this study aimed to evaluate the prevalence and the risk factors of IA and at-risk IA among employed adults in Japan.
Methods: This cross-sectional study surveyed all junior and senior high school personnel in Shimane Prefecture, a rural area in Japan. Eligible participants included 3,211 junior and senior high school personnel (1,259 men and 1,952 women). Participants completed a questionnaire on their activities and factors related to Internet use.
Results: The prevalence of IA and at-risk IA was 0.03% and 4.82%, respectively. Furthermore, game playing was shown to be the Internet activity most closely associated with at-risk IA.
Conclusions: This study showed that around 5% of school personnel in a rural area in Japan are at risk for developing addiction to the Internet and that using the Internet for game playing is related to at-risk IA. Our results suggest that employed adults should be instructed to use the Internet properly.
Background: Many epidemiological studies have indicated a positive association between coffee intake and lung cancer risk, but such findings were suggested to be confounded by smoking. Furthermore, only a few of these studies have been conducted in Asia. Here, we investigated the association between coffee intake and lung cancer risk in one of the largest prospective cohort studies in Japan.
Methods: We investigated the association of coffee drinking and subsequent incidence of lung cancer among 41,727 men and 45,352 women in the Japan Public Health Center-based Prospective Study using Cox proportional hazards regression, with adjustment for potential confounders and by strata of smoking status. Coffee and other dietary intakes were assessed once at baseline with a food frequency questionnaire (FFQ).
Results: During 1,481,887 person-years of follow-up between 1990 and 2011, a total of 1,668 lung cancer cases were identified. In a multivariate regression model, coffee consumption was not associated with risk of lung cancer (HR 1.16; 95% CI, 0.82–1.63; Ptrend = 0.285 for men and HR 1.49; 95% CI, 0.79–2.83; Ptrend = 0.942 for women). However, there was a significant increase in the risk for small cell carcinoma (HR 3.52; 95% CI, 1.49–8.28; Ptrend < 0.001).
Conclusion: Our prospective study suggests that habitual consumption of coffee is not associated with an increased risk of lung cancer incidence, despite observing a significant increase in the risk for small cell carcinoma.
Previous systematic reviews of population-level tobacco control interventions and their effects on smoking inequality by socioeconomic factors concluded that tobacco taxation reduce smoking inequality by income (although this is not consistent for other socioeconomic factors, such as education). Inconsistent results have been reported for socioeconomic differences, especially for other tobacco control measures, such as smoke-free policies and anti-tobacco media campaigns. To understand smoking inequality itself and to develop strategies to reduce smoking inequality, knowledge of the underlying principles or mechanisms of the inequality over a long time-course may be important. For example, the inverse equity hypothesis recognizes that inequality may evolve in stages. New population-based interventions are initially primarily accessed by the affluent and well-educated, so there is an initial increase in socioeconomic inequality (early stage). These inequalities narrow when the deprived population can access the intervention after the affluent have gained maximum benefit (late stage). Following this hypothesis, all tobacco control measures may have the potential to reduce smoking inequality, if they continue for a long term, covering and reaching all socioeconomic subgroups. Re-evaluation of the impact of the interventions on smoking inequality using a long time-course perspective may lead to a favorable next step in equity effectiveness. Tackling socioeconomic inequality in smoking may be a key public health target for the reduction of inequality in health.
Background: Nutrients have been proposed to be related to metabolic syndrome (MetS). The aims of this study were to identify dietary patterns that correlated with several nutrients using reduced rank regression (RRR) and to examine the association between extracted dietary patterns and prevalence of MetS in a Japanese population.
Methods: The study population comprised 1,092 Japanese men and women (35–69 years old) who had participated in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study in Tokushima Prefecture. Dietary patterns were derived with RRR using 46 food items as predictors and six established nutrients (potassium, calcium, vitamin D, vitamin C, insoluble dietary fiber, and carotene) as response variables. Associations between extracted dietary patterns and MetS were then examined with logistic regression models.
Results: Among the six dietary patterns, dietary pattern 1 (DP1) explained the largest proportion (60.1%) of variance in the six nutrients. Therefore, only DP1 was selected for further analysis. DP1 was characterized by high intake frequency of vegetables, fruits, fish and small fish, natto (fermented soybeans), and deep-fried tofu. After adjustment for potential confounders, significant inverse associations were found between DP1 score and MetS (odds ratio [OR] for each quartile: 1.00, 0.58, 0.60, 0.52; Ptrend = 0.02); DP1 and high blood pressure (Ptrend = 0.0002); and DP1 and high blood glucose (Ptrend = 0.02).
Conclusion: A dietary pattern characterized by high intake of vegetables, fruits, fish and small fish, natto, and deep-fried tofu was associated with reduced prevalence of MetS in a Japanese population.
Background: In Japan, the rate of cervical cancer screening is remarkably low, especially among women in their twenties and thirties, when cervical cancer is now increasing dramatically. The aim of this study was to test whether a modified government reminder for 20-year-old women to engage in cervical cancer screening, acting through maternal education and by asking for a maternal recommendation to the daughter to receive the screening, could increase their participation rate.
Methods: In two Japanese cities, 20-year-old girls who had not received their first cervical cancer screening before October of fiscal year 2014 were randomized into two study arms. One group of 1,274 received only a personalized daughter-directed reminder leaflet for cervical cancer screening. In the second group of 1,274, the daughters and their mothers received a combination package containing the same reminder leaflet as did the first group, plus an additional informational leaflet for the mother, which requested that the mother recommend that her daughter undergo cervical cancer screening. The subsequent post-reminder screening rates of these two study arms were compared.
Results: The cervical cancer screening rate of 20-year-old women whose mothers received the information leaflet was significantly higher than that for women who received only a leaflet for themselves (11% vs 9%, P = 0.0049).
Conclusions: An intervention with mothers, by sending them a cervical cancer information leaflet with a request that they recommend that their daughter receive cervical cancer screening, significantly improved their daughters’ screening rate.
Background: We examined the associations of alcohol consumption and liver holidays with all-cause mortality and with mortality due to cancer, heart disease, cerebrovascular disease, respiratory disease, and injury using a large-scale prospective study in Japan.
Methods: We followed 102,849 Japanese who were aged between 40 and 69 years at baseline for 18.2 years on average, during which 15,203 deaths were reported. Associations between alcohol intake and mortality risk were assessed using a Cox proportional hazards model, with analysis by the number of liver holidays (in which a person abstains from drinking for several days a week).
Results: A J-shaped association was observed between alcohol intake and total mortality in men (nondrinkers: reference; occasional drinkers: hazard ratio [HR] 0.74; 95% confidence interval [CI], 0.68–0.80; 1–149 g/week: HR 0.76; 95% CI, 0.71–0.81; 150–299 g/week: HR 0.75; 95% CI, 0.70–0.80; 300–449 g/week: HR 0.84; 95% CI, 0.78–0.91; 450–599 g/week: HR 0.92; 95% CI, 0.83–1.01; and ≥600 g/week: HR 1.19; 95% CI, 1.07–1.32) and in women (nondrinkers: reference; occasional: HR 0.75; 95% CI, 0.70–0.82; 1–149 g/week: HR 0.80; 95% CI, 0.73–0.88; 150–299 g/week: HR 0.91; 95% CI, 0.74–1.13; 300–449 g/week: HR 1.04; 95% CI, 0.73–1.48; and ≥450 g/week: HR 1.59; 95% CI, 1.07–2.38). In current drinkers, alcohol consumption was associated with a linear, positive increase in mortality risk from all causes, cancer, and cerebrovascular disease in both men and women, but not heart disease in men. Taking of liver holidays was associated with a lower risk of cancer and cerebrovascular disease mortality in men.
Conclusions: Alcohol intake showed J-shaped associations with the risk of total mortality and three leading causes of death. However, heavy drinking increases the risk of mortality, which highlights the necessity of drinking in moderation coupled with liver holidays.
Background: This study examined the annual prevalence of atrial fibrillation (AF) and its associated comorbidities, as well as the prevalence of warfarin therapy in South Korean patients with AF.
Methods: The National Health Insurance Service-National Sample Cohort database was searched for subjects aged ≥30 years diagnosed with AF from 2002–2013. The prevalence of AF was analyzed by sex and age, as was the current status of warfarin therapy in AF patients according to CHA2DS2-VASc score and comorbidities.
Results: The age-standardized prevalence of AF in men and women was 0.15% and 0.14%, respectively, in 2002, increasing to 0.54% and 0.39%, respectively, in 2013. In 2013, the prevalence of AF in men and women aged 30–39 years was 0.08% and 0.03%, respectively, increasing to 2.35% and 1.71%, respectively, in those in aged ≥60 years. During 2002–2013, the prevalence of AF in men significantly increased among subjects aged ≥30 years and increased in women aged ≥60 years. The age-standardized prevalence of hypertension and diabetes mellitus among AF patients were markedly increased during 2002–2013. Of these AF patients, 86.1% had a CHA2DS2-VASc score of ≥2; however, only 39.1% of these were receiving warfarin.
Conclusions: The age-standardized prevalence of AF increased 2.89-fold over the 12-year study period. The total number of patients with AF in South Korea has been drastically increasing, due to not only aging society but also increasing age-specific prevalence of AF, especially in middle-aged and elderly individuals. The rate of warfarin therapy increased slightly over the study period but remains low.
Background: Medical circumstances in Japanese patients with cancer of the corpus uteri have greatly changed since the late 1990s, including the introduction of concomitant therapy with taxane and platinum. We evaluated changes in survival rates for this cancer following these advances by analyzing data from population-based cancer registries in Japan.
Methods: Data were available for 8562 cases of cancer of the corpus uteri from six prefectural cancer registries. We defined the two periods of 1993–2000 (1st period) and 2001–2006 (2nd period). Relative survival (RS) in each period was calculated to assess changes using an excess mortality model, with adjustment for age group (15–54, 55–69, and 70–99 years), extent of disease (localized, regional, and distant), and histological subtype.
Results: Overall 5-year RS improved from 77.7% in the 1st period to 80.2% in the 2nd period, with an excess hazard ratio (EHR) of 0.785 (95% confidence interval [CI], 0.705–0.873). Five-year RS significantly improved in the group aged 55–69 years, in all groups by extent of disease, and in the endometrioid adenocarcinoma group. In particular, 5-year RS significantly improved in patients with endometrioid adenocarcinoma, from 84.5% to 89.7%, with an EHR of 0.698 (95% CI, 0.560–0.870).
Conclusion: Overall 5-year RS for cancer of the corpus uteri in Japan improved from the 1990s to early 2000s. These improvements might have been aided by the comprehensive medical development of management for this cancer, including the spread of concomitant therapy with taxane and platinum as a standard adjuvant chemotherapy in the early 2000s.
Background: Prevalence rates of all anomalies classified as birth defects, including those identified before the 22nd gestational week, are limited in published reports, including those from the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). In our birth cohort study, we collected the data for all birth defects after 12 weeks of gestation.
Methods: Subjects in this study comprised 19,244 pregnant women who visited one of 37 associated hospitals in the Hokkaido Prefecture from 2003 through 2012, and completed follow-up. All birth defects after 12 weeks of gestation, including 55 marker anomalies associated with environmental chemical exposures, were recorded. We examined parental risk factors for birth defects and the association between birth defects and risk of growth retardation.
Results: Prevalence of all birth defects was 18.9/1,000 births. The proportion of patients with birth defects delivered between 12 and 21 weeks of gestation was approximately one-tenth of all patients with birth defects. Among those with congenital malformation of the nerve system, 39% were delivered before 22 weeks of gestation. All patients with anencephaly and encephalocele were delivered before 22 weeks of gestation. We observed different patterns of parental risk factors between birth defect cases included in ISBDSR and cases not included. Cases included in ISBDSR were associated with an increased risk of preterm birth. Cases not included in ISBDSR were associated with an increased risk of being small for gestational age at term.
Conclusions: Data from our study complemented the data from ICBDSR. We recommend that birth defects not included in ICBDSR also be analyzed to elucidate the etiology of birth defects.
Background: Few studies have investigated the work continuance rate among cancer survivors after return to work (RTW). The objective of this study was to clarify work sustainability after RTW among Japanese male cancer survivors.
Methods: We collected data on male cancer survivors from an occupational health register. Inclusion criteria were as follows: employees who returned to work after an episode of sick leave due to clinically certified cancer diagnosed between January 1, 2000 and December 31, 2011.
Results: Of 1,033 male employees who were diagnosed with cancer, 786 employees (76.1%) returned to work after their first episode of sick leave due to cancer. Work continuance rates among all subjects were 80.1% 1 year after RTW and 48.5% 5 years after RTW. The mean duration of work after RTW was 4.5 years. The work continuance rates varied significantly by cancer type. The “Lung” and “Hepatic, Pancreatic” cancer groups had the shortest duration of work (0.9 year after RTW).
Conclusions: Of workers who returned to work after their first episode of leave after cancer, 50% continued to work after 5 years in large-scale companies. There was a steep decrease in work continuance rates during the first year after RTW, with considerable differences according to cancer site.
Background: Japanese rice cake (“mochi”) is a major cause of food-choking accidents in Japan. However, the epidemiology of out-of-hospital cardiac arrests (OHCAs) due to suffocation caused by rice cakes is poorly understood.
Methods: OHCA data from 2005 to 2012 were obtained from the population-based OHCA registry in Osaka Prefecture. Patients aged ≥20 years who experienced OHCA caused by suffocation that occurred before the arrival of emergency-medical-service (EMS) personnel were included. Patient characteristics, prehospital interventions, and outcomes were compared based on the cause of suffocation (rice cake and non-rice-cake). The primary outcome was 1-month survival after OHCA.
Results: In total, 46 911 adult OHCAs were observed during the study period. Of the OHCAs, 7.0% (3,294/46,911) were due to suffocation, with choking due to rice cake as the cause in 9.5% of cases (314/3,294), and of these, 24.5% (77/314) occurred during the first 3 days of the New Year. In crude analysis, 1-month survival was 17.2% (54/314) in those with suffocation caused by rice cake and 13.4% (400/2,980) in those with suffocation due to other causes. In the multivariable analysis for all-cause suffocation, younger age, arrest witnessed by bystanders, and earlier EMS response time were significantly related to better 1-month survival.
Conclusion: Approximately 10% of OHCAs due to suffocation were caused by rice-cake choking, and 25% of these occurred during the first 3 days of the New Year. Further efforts for establishing preventive measures as well as improving the early recognition of choking and encouraging bystanders to call EMS sooner are needed.
Background: Survival rate is used to develop cancer control plans. However, there are limitations and biases when interpreting patient survival rate data. This study aimed to identify and account for potential biases and/or limitations on estimating survival rate to enable more effective control of cancer.
Methods: The authors searched PubMed from December 2010 to December 2015 for articles that investigated or described biases in estimating patient survival using cancer registries. Articles that only described the tendency of survival rate and investigated relationships between patient characteristics, treatment, and survival rate were excluded.
Results: In total, 50 articles met the inclusion criteria. The identified potential biases were categorized into three areas, as follows: 1) the quality of registry data (eg, the completeness of cancer patients, accuracy of data, and follow-up rates); 2) limitations related to estimated methods of survival rates (eg, misclassification of cause of death for cause-specific survival rate or a lack of comparability of background mortality for relative survival rate); and 3) the comparability of survival rates among different groups (eg, age-adjustment or patients with multiple cancers).
Conclusion: We concluded that survival rate can be suitable for answering questions related to health policy and research. Several factors should be considered when interpreting survival rates estimated using cancer registries.
Background: Secondhand smoke (SHS) causes many deaths. Inequalities in SHS have been reported in several countries; however, the evidence in Asian countries is scarce. We aimed to investigate the association between socioeconomic status (SES) and SHS at home and the workplace/school among non-smoking Japanese adults.
Methods: Cross-sectional data from the Miyagi Prefectural Health Survey 2014 were analyzed. Self-reported questionnaires were randomly distributed to residents ≥20 years of age and 2,443 (92.8%) responded. The data of the 1,738 and 1,003 respondents were included to the analyses for SHS in the past month at home and at the workplace/school, respectively. Ordered logistic regression models considering possible confounders, including knowledge of the adverse health effects of tobacco, were applied.
Results: The prevalence of SHS at home and the workplace/school was 19.0% and 39.0%, respectively. Compared with ≥13 years of education, odds ratios (ORs) and 95% confidence intervals (CIs) for SHS at home were 1.94 (95% CI, 1.42–2.64) for 10–12 years and 3.00 (95% CI, 1.95–4.60) for ≤9 years; those for SHS at the workplace/school were 1.80 (95% CI, 1.36–2.39) and 3.82 (95% CI, 2.29–6.36), respectively. Knowledge of the adverse health effects of tobacco was significantly associated with lower SHS at home (OR 0.95; 95% CI, 0.91–0.98) but it was not associated with SHS at the workplace/school (OR 1.02; 95% CI, 0.98–1.06).
Conclusions: Social inequalities in SHS existed among Japanese non-smoking adults. Knowledge about tobacco was negatively associated with SHS at home but not at workplace/school.
Background: Although reducing socioeconomic inequalities in depression is necessary, their associated factors have rarely been studied. This study aimed to screen the potential contextual factors associated with income-based inequality in older adults’ depression.
Methods: Using data from the Japan Gerontological Evaluation Study (JAGES) of 2013, we conducted an ecological study covering 77 communities in Japan. Our measures of socioeconomic inequalities in depression were the slope index of inequalities (SII) and the relative index of inequalities (RII) of the prevalence of depressive symptoms across three income levels. We categorized available community-level factors, including socio-demographic factors, social participation, social relationships, subjective changes in the residential area, and the built environment. These indicators were aggregated from individual responses of 51,962 and 52,958 physically independent men and women, respectively, aged 65 years or more. We performed multiple linear regression analyses to explore factors with statistical significance of a two-tailed P-value less than 0.05.
Results: Factors associated with shallower gradients in depression for men included higher participation in local activities and reception or provision of social support, which did not show significant association among women. Perceived increases in unemployment and economic inequalities were positively associated with larger inequalities in both genders (P < 0.05). The built environment did not indicate any significant association.
Conclusions: A community environment fostering social activities and relationships might be associated with smaller income-based inequalities in depression. There is a need for more deterministic studies for planning of effective community interventions to address socioeconomic inequalities in depression.
Background: Good quality measures of Japanese adults’ sedentary behaviors are needed to accurately assess correlates of specific sedentary behaviors. The present study assessed criterion validity of total sedentary behavior and test-retest reliability of six domain-specific sedentary behaviors.
Methods: We administered a questionnaire, based on previous studies, that measured domain-specific sedentary behaviors. To examine validity, agreement between self-reported time spent in sedentary behaviors from the questionnaire and objectively-measured sedentary time using accelerometers was compared among 392 adults (aged 40–64 years) in two Japanese cities. For reliability, a 2-week interval test-retest was administered to a convenience sample of 34 participants.
Results: The correlation between total self-reported and objectively measured sedentary time was significant (all P < 0.001) and fair-to-good for workdays (ρ = 0.57) and whole week (ρ = 0.49), but was low for non-workdays (ρ = 0.23). The difference between the two measures was significant for whole week (z = −2.25, P = 0.03) and non-workdays (z = −5.50, P < 0.001), but was not significant for workdays (z = −0.60, P = 0.55). There was a significant positive association between the difference in the two measures and the average of these two measures (workdays: r = 0.53; non-workdays: r = 0.45; and whole week: r = 0.54, all P < 0.001). There was fair-to-good test-retest reliability of total sedentary time for each domain (workdays: interclass correlation coefficient [ICC] = 0.77, non-workdays: ICC = 0.53, and whole week: ICC = 0.7; all P < 0.01).
Conclusions: The scale of domain-specific sedentary behaviors is reliable for estimating where and for what purpose Japanese adults spend their sedentary time, and total sedentary time is valid for workdays and the whole week.
Background: Data on the effect of physical activity intensity on depression is scarce. We investigated the prospective association between intensity of leisure-time exercise and risk of depressive symptoms among Japanese workers.
Methods: The participants were 29,052 employees (24,653 men and 4,399 women) aged 20 to 64 years without psychiatric disease including depressive symptoms at health checkup in 2006–2007 and were followed up until 2014–2015. Details of leisure-time exercise were ascertained via a questionnaire. Depressive states were assessed using a 13-item questionnaire. Multivariable-adjusted hazard ratio of depressive symptoms was estimated using Cox regression analysis.
Results: During a mean follow-up of 5.8 years with 168,203 person-years, 6,847 workers developed depressive symptoms. Compared with workers who engaged in no exercise during leisure-time (0 MET-hours per week), hazard ratios (95% confidence intervals) associated with >0 to <7.5, 7.5 to <15.0, and ≥15.0 MET-hours of leisure-time exercise were 0.88 (0.82–0.94), 0.85 (0.76–0.94), and 0.78 (0.68–0.88) among workers who engaged in moderate-intensity exercise alone; 0.93 (0.82–1.06), 0.82 (0.68–0.98), and 0.83 (0.71–0.98) among workers who engaged in vigorous-intensity exercise alone; and 0.96 (0.80–1.15), 0.80 (0.67–0.95), and 0.76 (0.66–0.87) among workers who engaged in both moderate- and vigorous-intensity exercise with adjustment for age, sex, lifestyles, work-related and socioeconomic factors, and body mass index. Additional adjustment for baseline depression score attenuated the inverse association, especially among those who engaged in moderate-intensity exercise alone.
Conclusions: The results suggest that vigorous-intensity exercise alone or vigorous-intensity combined with moderate-intensity exercise would prevent depressive symptoms among Japanese workers.
Background: We aimed to investigate the association between alcohol drinking patterns and the presence of impaired fasting glucose (IFG) and diabetes mellitus (DM).
Methods: We used data from the Korean National Health and Nutrition Examination Survey, 2010–2014. The participants were aged ≥30 years and had no previous diagnosis of DM. High-risk drinking was defined as alcohol consumption of ≥7 glasses at a sitting for men, and ≥5 glasses for women. After adjusting for confounding factors, a polychotomous logistic regression analysis was performed to assess the association of drinking patterns with IFG and DM.
Results: For men, high-risk drinking was associated with higher odds ratios (ORs) of IFG (2–4/month, OR 1.51; 95% confidence interval [CI], 1.13–2.04; 2–3/week, OR 1.79; 95% CI, 1.38–2.33; and ≥4/week, OR 2.24; 95% CI, 1.65–3.03) and of DM (2–4/month, OR 2.12; 95% CI, 1.20–3.77; 2–3/week, OR 1.78; 95% CI, 1.05–3.03; and ≥4/week, OR 2.98; 95% CI, 1.72–5.17). For women, high-risk drinking was associated with higher risk of IFG (2–4/month, OR 1.51; 95% CI, 1.04–2.21; 2–3/week, OR 3.19; 95% CI, 2.20–4.64; and ≥4/week, OR 2.23; 95% CI, 1.23–4.06), but not of DM, compared with non-high-risk drinkers who consumed alcohol ≤1 day/month. Non-high-risk drinkers who consumed alcohol ≥4 days/week had higher ORs of DM in men, but lower ORs of DM in women compared with non-high risk drinkers who consumed alcohol ≤1 day/month.
Conclusions: Compared with non-high-risk alcohol drinking, even occasional high-risk alcohol drinking was associated with a higher risk of IFG in men and women, and DM in men. Nearly daily non-high-risk alcohol drinking was associated with a higher risk of DM in men and lower risk of DM in women.
Background: The Japan Environment and Children’s Study (JECS), known as Ecochil-Chosa in Japan, is a nationwide birth cohort study investigating the environmental factors that might affect children’s health and development. We report the baseline profiles of the participating mothers, fathers, and their children.
Methods: Fifteen Regional Centres located throughout Japan were responsible for recruiting women in early pregnancy living in their respective recruitment areas. Self-administered questionnaires and medical records were used to obtain such information as demographic factors, lifestyle, socioeconomic status, environmental exposure, medical history, and delivery information. In the period up to delivery, we collected bio-specimens, including blood, urine, hair, and umbilical cord blood. Fathers were also recruited, when accessible, and asked to fill in a questionnaire and to provide blood samples.
Results: The total number of pregnancies resulting in delivery was 100,778, of which 51,402 (51.0%) involved program participation by male partners. Discounting pregnancies by the same woman, the study included 95,248 unique mothers and 49,189 unique fathers. The 100,778 pregnancies involved a total of 101,779 fetuses and resulted in 100,148 live births. The coverage of children in 2013 (the number of live births registered in JECS divided by the number of all live births within the study areas) was approximately 45%. Nevertheless, the data on the characteristics of the mothers and children we studied showed marked similarity to those obtained from Japan’s 2013 Vital Statistics Survey.
Conclusions: Between 2011 and 2014, we established one of the largest birth cohorts in the world.