Background: Encouraging older adults to continue working longer would be a realistic solution to the shrinking labor force, which is a result of the aging population. This study examined whether working longer improves the health of older adults.

Methods: We used repeated cross-sectional data from 1,483,591 individuals aged 55–69 years collected from 11 waves of a nationwide population-based survey conducted in Japan from 1986 to 2016. We estimated pooled regression models to explain health outcomes by work status, controlling for potential endogeneity biases. Based on the estimation results, we conducted simulations to predict the health impact of policy measures that encourage older adults to participate in the labor force.

Results: The regression analysis showed that work status had a mixed health impact. For example, work reduced the probability of poor self-rated health by 6.7 (95% confidence interval [CI]: 6.2–7.2) percentage points and increased that of psychological distress by 12.2 (95% CI: 11.3–13.1) percentage points. The simulation results showed that raising both the mandatory retirement age and eligibility age for claiming public pension benefits to 70 years would increase the employment rate by 27.8 (standard deviation [SD]: 4.2) percentage points among those aged 65–69 years, which would reduce their probability of poor self-rated health by 1.8 (SD: 0.4) percentage points and raise that of psychological distress by 4.1 (SD: 0.8) percentage points for that age group.

Conclusions: The results suggest the need to pay attention to the health outcomes of policy measures that encourage older adults to work longer.

Background: To provide a better healthcare system for patients with mitochondrial diseases, it is important to understand the basic epidemiology of these conditions, including the number of patients affected. However, little information about them has appeared in Japan to date.

Methods: To gather data of patients with mitochondrial diseases, we estimated the number of patients with mitochondrial diseases from April 2018 to March 2019 using a national Japanese health care claims database, the NDB (National Database). Further, we calculated the prevalence of patients, and sex ratio, age class, and geographical distribution.

Results: From April 2018 to March 2019, the number of patients with mitochondrial diseases was 3,629, and the prevalence was 2.9 per 100,000 general population (95% CI, 2.8-3). The ratio of females and males was 53 to 47, and the most frequent age class was 40-49 years old. Tokyo had the greatest number of patients with mitochondrial diseases, at 477, whereas Yamanashi had the fewest, at 13. Kagoshima had the highest prevalence of patients with mitochondrial diseases, 8.4 (95% CI, 7.1-10) per 100,000 population, whereas Yamanashi had the lowest, 1.6 (95% CI, 0.8-2.7).

Conclusion: The number of patients with mitochondrial diseases estimated by this study, 3,269, was more than double that indicated by the Japanese government. This result may imply that about half of all patients are overlooked for reasons such as low severity of illness, suggesting that the Japanese healthcare system needs to provide additional support for these patients.

Background: While a wide range of predictors of postpartum smoking relapse have been suggested, population-based studies have rarely examined these factors exclusively among women who quit in early pregnancy. Furthermore, workplace secondhand smoke (SHS) exposure has never been examined.

Methods: We analyzed data from 10,466 pregnant women who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Age, education, parity, breastfeeding, postpartum depression, SHS exposure at home, and SHS exposure at work (not working, working without SHS exposure, working with SHS exposure) were evaluated as possible predictors. Multiple logistic regression analyses were conducted to examine the associations between these factors and smoking relapse by 1 year postpartum among women who quit in early pregnancy. Analyses stratified by SHS exposure at home were also conducted.

Results: About one-fourth of early-pregnancy quitters had relapsed into smoking by 1 year postpartum. Lower education, multiparity, not breastfeeding, postpartum depression, and SHS exposure at home were associated with increased risks of smoking relapse. Working with SHS exposure was associated with an increased risk of smoking relapse; the multivariate-adjusted odds ratios (95% confidence intervals) of working without SHS exposure and working with SHS exposure compared with not working were 1.14 (0.82–1.59) and 2.18 (1.37–3.46), respectively. The significant association of workplace SHS exposure was observed only among women without SHS exposure at home.

Conclusions: SHS exposure at work, as well as education, multiparity, breastfeeding, postpartum depression, and SHS exposure at home were associated with postpartum smoking relapse among early-pregnancy quitters.

Background: Helicobacter pylori (H. pylori) is an established causative factor of gastric cancer. Although the expansion of insurance coverage has led to an increase in the number of patients treated for H. pylori, the population impact of eradication treatment for H.pylori has been scarcely investigated. This study aimed to clarify the long-term responses of H. pylori antibody titer after eradication treatment using large scale cross-sectional data from the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT Study).

Methods: A total of 55,282 Japanese participants aged 40 to 74 years residing in 16 areas provided blood samples between 2011 and 2016. From these, treated (n=6,276) and untreated subjects who were seropositive for H. pylori or had serological atrophy (n= 22,420) formed the study population (n=28,696). Seropositivity was defined as an anti-H. pylori IgG titer of ≥10 U/mL. Antibody level was compared among subjects according to self-reported treatment history as untreated, and treated for less than one year (<1Y), one to five years (1-5Y), and more than six years ago (6Y+).

Results: Median serum antibody titer was 34.0 U/mL, 7.9 U/mL, 4.0 U/mL, and 2.9 U/mL for the Untreated, <1Y, 1-5Y, and 6Y+ groups, respectively. While those treated for H.pylori within the previous year had a 76.8% lower antibody titer compared to untreated subjects, approximately 41% of subjects were still seropositive.

Conclusions: A significant reduction in H.pylori antibody titer occurs within one year after eradication treatment, but that a long period is needed to achieve complete negative conversion.

Background: Online peer support groups are common and can be an effective tool for mothers with young children. The purpose of this review is to examine the types of support that online-based peer groups establish, as well as its health effects on mothers and their children.

Methods: Systematic scoping review. Systematic review of existing literature was conducted using PubMed, CINAHL, Medline, Cochrane and Ichushi (Japanese language) database in December 2019.

Results: Based on the inclusion and exclusion criteria, a total of 1,475 articles were extracted by initial search. After the review of titles, abstracts and full texts, a total of 21 articles met the inclusion criteria. The types of support mothers received were mainly informational and emotional support. Mothers also felt a sense of connection and community. Some health effects of online-based peer support group were seen in the area of mothers’ mental well-being. Minimal effects were seen in behavioral modification for child nutrition and breastfeeding.

Conclusion: Due to the limited evidence in interventional studies, the effects of online-based peer support groups were inconclusive. Further studies with rigorous research designs would be helpful in future research.

Background: Japan’s historically low immigration rate and monolingual culture makes it a particularly interesting setting for clarifying non-national medical care. Our study objective was to examine disease patterns and outcome differences between Japanese and non-Japanese patients in a rapidly globalizing nation.

Methods: A secondary data analysis of 325 non-Japanese and 13,370 Japanese patients requiring tertiary care or intensive-care unit or high-care unit admission to the emergency department at the Tokyo Medical and Dental University medical hospital from 2010 through 2019 was conducted. Multivariable linear and logistic regressions models were applied to examine differences in percentage of diagnosis, mortality rates, and length of stay, stratified by Glasgow Coma Scale (GCS) scores to consider the impact of language barriers. Sex and age were adjusted.

Results: Non-Japanese patients had more anaphylaxis, burns, and infectious disease, but less cardiovascular diagnoses prior to adjustment. After adjustment, there were significantly more anaphylaxis (adjusted odds ratio [aOR] 2.7; 95% confidence interval [CI], 1.7–4.4) and infectious disease diagnoses (aOR 2.2; 95% CI, 1.3–3.7), and marginally more burn diagnoses (aOR 2.3; 95% CI, 0.96–5.3) than Japanese patients. Regardless of GCS scores, there were no significant differences between non-Japanese and Japanese patient length of stay for anaphylaxis, burn, and infectious disease after covariate adjustment.

Conclusion: There were more non-Japanese patients diagnosed with anaphylaxis, burns, and infectious disease, but no notable patient care differences for length of stay. Further prevention efforts are needed against anaphylaxis, burns, and infectious disease for non-Japanese tourists or residents.

Background: Both weight loss and cognitive impairment are common in late-life, but it remains unknown whether weight change is associated with risk of incident dementia among elderly Japanese. Our study aimed to investigate the association between long-term weight change since midlife and risk of incident disabling dementia using a community-based cohort study of elderly Japanese.

Methods: In 2006, we conducted a cohort study of 6,672 disability-free Japanese adults aged ≥65 years. In both 1994 and 2006, the participants reported their weight using a self-reported questionnaire. Based on weight obtained at these two time points, participants were classified into: stable weight (−1.4 to +1.4 kg), weight gain (≥+1.5 kg), and weight loss of −2.4 to −1.5 kg, −3.4 to −2.5 kg, −4.4 to −3.5 kg, −5.4 to −4.5 kg, and ≥−5.5 kg. Incident disabling dementia was retrieved from the public Long-term Care Insurance database. Participants were followed-up for 5.7 years (between April 2007 and November 2012). Cox proportional hazards model was used to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident disabling dementia.

Results: During 32,865 person-years of follow-up, 564 participants were ascertained as having incident disabling dementia. Compared with stable weight, the multivariable-adjusted HRs were 0.97 (95% CI, 0.70–1.34) for weight loss of −2.4 to −1.5 kg, 0.98 (95% CI, 0.70–1.38) for −3.4 to −2.5 kg, 1.28 (95% CI, 0.91–1.81) for −4.4 to −3.5 kg, 1.27 (95% CI, 0.92–1.77) for −5.4 to −4.5 kg, and 1.64 (95% CI, 1.29–2.09) for ≥−5.5 kg.

Conclusion: Our study suggested that a ≥−3.5 kg weight loss over 12 years might be associated with higher risk of incident disabling dementia among elderly Japanese.

Background: Food allergies are common among children, and food-induced anaphylaxis (FIA) is a serious disease with a risk of death; however, there is yet to be a large-scale epidemiological study on causative foods in Japan. The purpose of this study was to identify foods that cause FIA in Japan.

Methods: We identified 9,079 patients from the Japanese Diagnosis Procedure Combination Database who were admitted for treatment for FIA from April 1, 2014 through March 31, 2017. We extracted data on patient sex, age, use of epinephrine injections on the first day, prescription for epinephrine self-injection on the day of discharge, length of stay, readmission, and causative foods.

Results: The most common causative food was eggs, followed by wheat, milk, peanuts, and buckwheat. The most common causative food in each age group was eggs among 0–3-year-olds, milk among 4–6-year-olds, peanuts among 7–19-year-olds, and wheat among those aged 20 years and older. Epinephrine was used at admission among about 40%, 50%, and over 60% of cases in which the causative food was eggs; wheat, milk and peanuts; and buckwheat, respectively. The proportion of cases with a prescription for epinephrine self-injection at discharge was highest among those in which the causative food was wheat, followed by peanuts, buckwheat, milk, and eggs.

Conclusions: FIA due to peanuts has become as common in Japan as it is in the West. These results suggest the importance of taking measures to prevent peanut allergies because children cannot make adequate decisions regarding food.

Background: The objective of this study is to describe the legislation regulating the use of electronic cigarettes (e-cigarettes) in various places in European countries.

Methods: A survey among experts from all countries of the World Health Organization (WHO) European Region was conducted in 2018. We collected and described data on legislation regulating e-cigarette use indoors and outdoors in public and private places, the level of difficulties in adopting the legislation, and the public support and compliance. Factors associated with the legislation adoption were identified with Poisson and linear regression analyses.

Results: Out of 48 countries, 58.3% had legislation on e-cigarette use at the national level. Education facilities were the most regulated place (58.3% of countries), while private areas (eg, homes, cars) were the least regulated ones (39.6%). A third of countries regulated e-cigarette use indoors. Difficulty and support in adopting the national legislation and its compliance were all at a moderate level. Countries’ smoking prevalence and income levels were linked to legislation adoption.

Conclusions: Although most WHO European Region countries had introduced e-cigarette use legislation at the national level, only a few of the legislation protect bystanders in indoor settings.

Background: The long-term effects of occupational injury (OI) on psychiatric diseases are unclear. This study assessed and compared the effects of OI, no injury (control), and non-OI (NOI) on the development of psychiatric diseases.

Methods: We used Taiwan’s National Health Insurance Research Database to investigate the incidence of psychiatric disorders in OI, NOI, and control groups. The subjects were aged 20–50 years, actively employed in 2000, and did not have history of injury or psychiatric disorders. All subjects were followed from 2000 and were classified into OI, NOI, and control groups according to occurrence of target injury later on. Individuals in each group were matched by age, sex, insurance premium before the index date, and year of the index date. Psychiatric disease-free days were compared among the groups using survival analysis and Cox regression.

Results: We included a total of 12,528 patients for final analysis, with 4,176 in each group. Compared with the control group, the OI group had an increased occurrence of trauma and stress-related disorder, depressive disorders, anxiety disorders, and alcohol and other substance dependence. These increases were similar to those in the NOI group. Elevated cumulative incidence rate of any psychiatric disorders was observed among those with OI or NOI up to 10 years after injury.

Conclusion: We confirmed that OI and NOI induced psychiatric disorders. These findings highlight the need for workers’ compensation mechanisms to consider long-term psychological care among injured workers.

Background: In April 2020, the Japanese government declared a state of emergency due to the COVID-19 pandemic, and infection control measures, including requests to work from home and stay-at-home restrictions, were introduced. This study examined changes in smoking behavior during the COVID-19 state of emergency.

Methods: An online cross-sectional survey was conducted in Osaka, Japan. To assess differences in smoking behavior among 5,120 current smokers before and after the declaration of a state of emergency, prevalence ratios (PRs) for two outcomes, increased smoking and quitting smoking, were calculated using multivariable Poisson regression, adjusting for potential covariates.

Results: We found 32.1% increased the number of cigarettes smoked and 11.9% quit smoking. After adjustment for all variables, we found risk factors for COVID-19 (men and older age group) had both significantly higher PR for quitting smoking (men: PR 1.38; 95% confidence interval [CI], 1.17–1.62) and participants aged ≥65 years: PR 2.45; 95% CI, 1.92–3.12) and significantly lower PR of increased smoking (men: PR 0.85; 95% CI, 0.78–0.93 and participants ≥65 years: PR 0.38; 95% CI, 0.29–0.49). Additionally, respondents working from home or living alone had significantly higher PR for increased smoking (working from home: PR 1.29; 95% CI, 1.17–1.41 and living alone: PR 1.23; 95% CI, 1.10–1.38) and respondents who changed from cigarettes to heated tobacco products (HTPs) had significantly lower PR for quitting smoking (PR 0.150; 95% CI, 0.039–0.582).

Conclusions: We suggest people who have high-risk factors for COVID-19 might change their smoking behavior for the better, while people who work from home or live alone might change their smoking behavior for the worse, during the COVID-19 state of emergency. Additionally, changing from smoking cigarettes to using HTPs makes smokers less likely to quit.

Background: As the COVID-19 pandemic spread, the Japanese government declared a state of emergency on April 7, 2020 for seven prefectures, and on April 16, 2020 for all prefectures. The Japanese Prime Minister and governors requested people to adopt self-restraint behaviors, including working from home and refraining from visiting nightlife spots. However, the effectiveness of the mobility change due to such requests in reducing the spread of COVID-19 has been little investigated. The present study examined the association of the mobility change in working, nightlife, and residential places and the COVID-19 outbreaks in Tokyo, Osaka, and Nagoya metropolitan areas in Japan.

Methods: First, we calculated the daily mobility change in working, nightlife, and residential places compared to the mobility before the outbreak using mobile device data. Second, we estimated the sensitivity of mobility changes to the reproduction number by generalized least squares.

Results: Mobility change had already started in March, 2020. However, mobility reduction in nightlife places was particularly significant due to the state of emergency declaration. Although the mobility in each place type was associated with the COVID-19 outbreak, the mobility changes in nightlife places were more significantly associated with the outbreak than those in the other place types. There were regional differences in intensity of sensitivity among each metropolitan area.

Conclusions: Our findings indicated the effectiveness of the mobility changes, particularly in nightlife places, in reducing the outbreak of COVID-19.

Background: Although prevalence of low birth weight has increased in the last 3 decades in Japan, no studies in Japanese women have investigated whether birth weight is associated with the risk of pregnancy complications, such as pregnancy-induced hypertension (PIH) and gestational diabetes mellitus (GDM).

Methods: We used data from the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT), a population-based cohort study in Japan that launched in 2011. In the main analysis, we included 46,365 women who had been pregnant at least once, for whom information on birth weight and events during their pregnancy was obtained using a self-administered questionnaire. Women were divided into five categories according to their birth weight, and the relationship between birth weight and risk of PIH and GDM was examined using multilevel logistic regression analyses with place of residence as a random effect.

Results: Compared to women born with birth weight of 3,000–3,999 grams, the risk of PIH was significantly higher among women born <1,500 grams (adjusted odd ratio [aOR] 1.60; 95% confidence interval [CI], 1.17–2.21), 1,500–2,499 grams (aOR 1.16; 95% CI, 1.03–1.30), and 2,500–2,999 grams (aOR 1.13; 95% CI, 1.04–1.22). The risk of GDM was significantly higher among women born 1,500–2,499 grams (aOR 1.20; 95% CI, 1.02–1.42), albeit non-significant association among women in other birthweight categories.

Conclusions: We observed an increased risk of PIH among women born with lower birth weight albeit non-significant increased risk of GDM among Japanese women.

Background: Procrastination is associated with stress and unhealthy behaviors. The oral condition reflects the long-term history of an individual’s stress exposure and oral health behaviors; however, empirical studies on the association of procrastination in childhood with remaining teeth in older age are limited. We investigated the association of procrastination in childhood with the number of remaining teeth among community-dwelling older Japanese adults.

Methods: In total, 1616 community-dwelling senior residents of Wakuya City (Miyagi Prefecture, Japan) who were enrolled in the National Health Plan & the Medical Care System for the Elderly completed a self-administered questionnaire on the number of teeth. Procrastination was measured using a single binary question about timing of holiday homework completion in childhood. The number of remaining teeth was assessed via a questionnaire with response options of ≥20, 10–19, 1–9, and 0 teeth. Ordered logistic regression models with potential confounders (sex, age, maternal education, childhood socioeconomic status (SES), childhood maltreatment, conscientiousness trait) and mediators (adulthood SES, smoking history, alcohol use history) were estimated.

Results: Forty-six percent of participants reported a higher tendency to procrastinate in childhood. The proportions of participants with ≥20, 10–19, 1–9, and 0 teeth were 39.6, 22.7, 24.0, and 13.7%, respectively. After adjusting for all covariates, a higher tendency to procrastinate in childhood was significantly associated with having fewer remaining teeth (odds ratio = 1.28; 95% confidence interval = 1.05–1.57).

Conclusion: A higher tendency to procrastinate in childhood was associated with having fewer remaining teeth in later life.

Background

Knee extensor muscle strength and cardiorespiratory fitness (CRF) are major components of physical fitness. Because the interactive association of knee extensor muscle strength and CRF with bone health remains unclear, we aimed to investigate such association in Japanese adults.

Methods

Altogether, 8,829 Japanese adults (3,731 men and 5,098 women) aged ≥45 years completed the maximum voluntary knee extension test, submaximal exercise test, medical examination, and a questionnaire on lifestyle habits. Using an osteo-sono assessment index, low bone stiffness tendency was defined as 80% under the young-adults mean. Multivariable odds ratios (ORs) and 95% confidence intervals (CIs) were calculated after confounder adjustment.

Results

Overall, 542 men (14.5%) and 978 women (19.2%) had low bone stiffness tendency. We observed an inverse association between muscle strength and low bone stiffness tendency after adjustment for CRF in both sexes (p for linear trend < 0.001). Compared with the lowest CRF, the multivariable ORs (95% CI) for low bone stiffness tendency in the highest CRF were 0.47 (0.36, 0.62) for men and 1.05 (0.82, 1.35) for post-menopausal women (p < 0.001 and p = 0.704, respectively). No interactive association between muscle strength and CRF for low bone stiffness tendency existed in both sexes and irrespective of menopausal status.

Conclusion

Knee extensor muscle strength and CRF were associated additively, not synergistically, with bone health. Maintaining high levels of both physical fitness components may improve musculoskeletal health in the cohort. The relationship between physical fitness and bone status should be longitudinally investigated in the future.

Background: To clarify the association between psychosocial problems and frailty in the areas affected by the Great East Japan Earthquake, and to develop strategies for preventive long-term care in the community, we launched the Kesennuma Study in 2019. This report describes the study design and the participants’ profiles at baseline.

Methods: The prospective study comprised 9,754 people (4,548 men, 5,206 women) randomly selected from community-dwelling independent adults aged 65 to 84 who were living in Kesennuma City, Miyagi. The baseline survey was conducted in October 2019. It included information on general health, socio-economic status, frailty, lifestyle, psychological factors (e.g. personality, depressive moods), and social factors (e.g. social isolation, social capital). A follow-up questionnaire survey is planned. Mortality, incident disability, and long-term care insurance certifications will also be collected.

Results: A total of 8,150 questionnaires were returned (83.6% response rate), and 7,845 were included in the analysis (80.4%, mean age [SD] 73.6 [5.5] years; 44.7% male). About 23.5% were considered frail. Regarding psychological and social functions, 42.7% had depressive moods, 29.1% were socially isolated, and only 37.0% participated in social activities at least once a month. However, 82.5% trusted their neighbours.

Conclusions: While local ties were strong, low social activity and poor mental health were revealed as issues in the affected area. Focusing on the association between psychological and social factors and frailty, we aim to delay the need for long-term care for as long as possible, through exercise, nutrition, social participation, and improvement of mental health.

Background: Screening or diagnosis for the elderly with dementia in rural regions might be delayed and underestimated due to limited utilization of healthcare resources. This study aimed to evaluate the disparities of prevalence and risk factors of mild cognitive impairment (MCI) and dementia between urban and rural residence.

Methods: In this nationwide door-to-door survey, 10,432 participants aged 65 years and more were selected by computerized random sampling from all administrative districts in Taiwan and were assessed by an in-person interview. We calculated the prevalence of MCI and dementia with their risk factors examined by multivariable logistic regression.

Results: The prevalence of dementia in rural, suburban, and urban areas among the elderly was 8.69% (95% CI, 8.68-8.69), 6.63% (95% CI, 6.62-6.63), and 4.46% (95% CI, 4.46-4.47), respectively. A similar rural-suburban-urban gradient relationship on the dementia prevalence was observed in any age and sex group. The rural/urban ratio was higher in women than in men for both MCI and dementia. Urbanization remained to be an independent factor for both MCI and dementia after adjustment for age, gender, education, lifestyle, and health status. The beneficial effects of exercise on dementia were more evident in rural areas than in urban ones.

Conclusions: Significantly higher prevalence of MCI and dementia were found in rural areas than in urban ones, especially for women. The odds of risk factors for MCI and dementia varied between urbanization statuses. Focus on the rural-urban inequality and the modification of associated factors specifically for different urbanization levels are needed.

Background: People with poor health or mental conditions are generally unwilling to participate in the health examinations, and no studies have directly examined the relationship of psychological distress among disaster survivors with participation status to date. The present study thus examined psychosocial differences according to the respondent status in a 5-year follow-up survey among participants in the prospective health surveys on survivors of the Great East Japan Earthquake and Tsunami Disaster study in Iwate prefecture, Japan.

Methods: We analyzed data from 10203 Japanese survivors aged ≥18 years (mean age, 65.6 years; 38.0% men) and who underwent health examinations at baseline in 2011. Participants were classified into responders and nonresponders according to their 2015 health examination participation status. Psychological distress was evaluated using the Kessler 6 scale and categorized as none, mild, and severe. Multinominal logistic regression was used to examine the risk of psychological distress in relation to participation status.

Results: In the 2015 survey, 6334 of 6492 responders and 1686 of 3356 nonresponders were analyzed. The most common reasons for nonparticipation in the survey were participated in other health examinations, examined at a hospital, and did not have time to participate. Nonresponse in males was associated only with mild psychological stress, whereas nonresponse in females was associated with mild and severe psychological distress.

Conclusions: Nonresponders in the follow-up survey had a higher risk of psychological distress than responders. Continuous monitoring of the health of nonresponders and responders may help to prevent future health deterioration.

Background: Detailed data on intensive care unit (ICU) occupancy in Japan are lacking. Using a nationwide inpatient database in Japan, we aimed to assess ICU bed occupancy to guide critical care utilization planning.

Methods: We identified all ICU patients admitted from January 1, 2015 to December 31, 2018 to ICU-equipped hospitals participating in the Japanese Diagnosis Procedure Combination inpatient database. We assessed the trends in daily occupancy by counting the total number of occupied ICU beds on a given day divided by the total number of licensed ICU beds in the participating hospitals. We also assessed ICU occupancy for patients with mechanical ventilation, patients with extracorporeal membrane oxygenation, and patients without life-supportive therapies.

Results: Over the 4 study years, 1,379,618 ICU patients were admitted to 495 hospitals equipped with 5,341 ICU beds, accounting for 75% of all ICU beds in Japan. Mean ICU occupancy on any given day was 60%, with a range of 45.0% to 72.5%. Mean ICU occupancy did not change over the 4 years. Mean ICU occupancy was about 9% higher on weekdays than on weekends and about 5% higher in the coldest season than in the warmest season. For patients with mechanical ventilation, patients with extracorporeal membrane oxygenation, and patients without life-supportive therapies, mean ICU occupancy was 24%, 0.5%, and 30%, respectively.

Conclusion: Only one-fourth of ICU beds were occupied by mechanically ventilated patients, suggesting that the critical care system in Japan has substantial surge capacity under normal temporal variation to care for critically ill patients.

Background: Chronic kidney disease (CKD) is an important contributor to morbidity and mortality from noncommunicable diseases. We aimed to examine the longitudinal trajectories in risk factors, estimate their impact on CKD burden in China from 1991 to 2011, and project trends in the next 20 years.

Methods: We used data from a cohort of the China Health and Nutrition Survey and applied the comparative risk assessment method to estimate the number of CKD events attributable to all non-optimal levels of each risk factors.

Results: In 2011, current smoking was the leading individual attributable factor for CKD burden in China responsible for 7.9 (95% CI, 7.5-8.3) million CKD cases with a population-attributable fraction of 8.7% (95% CI, 6.0-11.6), while the rates of smoking have reduced and may have mitigated the increase in CKD. High triglyceride (TG) and high systolic blood pressure (SBP) were the leading metabolic risk factors responsible for 6.8 (95% CI, 6.4-7.1) million and 5.8 (95% CI, 5.5-6.1) million CKD-attributable cases, respectively. Additionally, the number of CKD cases associated with high body mass index (BMI), high diastolic blood pressure (DBP), high plasma glucose, and low high-density lipoprotein cholesterol (HDL-C) was 5.4 (95% CI, 5.1-5.6), 3.9 (95% CI, 3.7-4.1), 3.0 (95% CI, 2.8-3.1) and 2.6 (95% CI, 2.5-2.8) million, respectively.

Conclusions: Current smoking, high TG, and high SBP were the top three risk factors that contributed to CKD burden in China. Increased BMI, DBP, plasma glucose, and decreased HDL-C were also associated with the increase in CKD burden.

Background: The proportion of overweight individuals living in the evacuation zone of Fukushima increased after the Great East Japan Earthquake. However, the change in the prevalence of abdominal obesity has not been reported. Lifestyle habits and changes in these habits after the disaster might have affected the onset of abdominal obesity; however, the association between the two is unclear.

Methods: This study evaluated 19,673 Japanese participants of the Fukushima Health Management Survey. We used data from general health check-ups conducted in 13 municipalities between 2008 and 2010. Follow-up examinations were performed from June 2011 to March 2013. Changes in the proportion of individuals with abdominal obesity before and after the disaster were compared. Then, lifestyle habits affecting these changes were assessed.

Results: We found that 34.2% and 36.6% of participants (P < 0.001), both evacuees (37.0% and 42.1% (P < 0.001)) and non-evacuees (32.8% and 34.0% (P < 0.001)), had abdominal obesity before and after the disaster, respectively. Abdominal obesity was positively associated with smoking cessation, snacking after dinner and non-breakfast skipping after the disaster and alcohol drinking before and after the disaster (all P < 0.05). Smoking cessation was positively associated with abdominal obesity in both evacuees and non-evacuees and in both men and women (all P < 0.01).

Conclusions: The prevalence of abdominal obesity increased among residents in the area affected by nuclear disaster. It might be associated with not only lifestyle habits before the disaster but also changes in these habits after the disaster, especially smoking cessation.

Background: Although social participation has been reported to be associated with significantly lower risks of mortality and disability, to our knowledge, no study has estimated its impact on disability-free life expectancy (DFLE). Therefore, this study aimed to investigate the association between social participation and DFLE in community-dwelling older people.

Methods: We analyzed 11-year follow-up data from a cohort study of 11,982 Japanese older adults (age ≥65 years) in 2006. We collected information on the number of social participation using a questionnaire. Using this information, we categorized the participants into four groups. DFLE was defined as the average number of years a person could expect to live without disability. The multistate life table method using Markov model was employed for calculating DFLE.

Results: The results revealed that DFLE (95% confidence interval) according to the number of social participation was 17.8 years (17.3–18.2) for no activities, 20.9 (20.4–21.5) for one activity, 21.5 (20.9–22.0) for two activities, and 22.7 (22.1–23.2) for three activities in men, and 21.8 (21.5–22.2), 25.1 (24.6–25.6), 25.3 (24.7–25.9), and 26.7 years (26.1–27.4), respectively, in women. This difference in DFLE did not change after the participants were stratified for smoking, body mass index, physical activity, and depression.

Conclusions: Social participation is associated with longer DFLE among Japanese older people; therefore, encouraging social participation at the population level could increase life-years lived in good health.

Background: The Free/Low-Cost Medical Care Program (FLCMC) can subsidize the payment (exempt/lower) in designated institutions in Japan. Given that poverty is a multidimensional concept including social isolation, the FLCMC applicants may need social support over and above financial aid to improve their quality of life. However, there was no data to discuss what services should be provided and to whom. Hence, we aimed to describe the changes in health-related quality of life scores among users of the FLCMC, with respect to their socioeconomic backgrounds.

Methods: This cohort study included patients who newly used FLCMC from July 2018 to April 2019. We used patients’ social work records, obtained at baseline, and self-report questionnaires on the Medical Outcomes Study 8 Items Short Form Health Survey (SF-8), measured both at baseline and six-month-after the application. We used the change in physical and mental health component summary score (PCS-8 and MCS-8) as outcome variables.

Results: Multiple linear regression analyses, adjusting for age, sex, healthcare institute, and baseline PCS-8 and MCS-8, showed that lower income was associated with an increase in PCS-8 (coef. -0.09; 95% CI, -0.15 to, -0.03) and MCS-8 (coef. -0.04; 95% CI, -0.11, to 0.03). Living alone (versus. living with someone) was potentially associated with a decrease in both PCS-8 (coef. -1.58; 95% CI, -7.26 to 4.09) and MCS-8 (coef. -3.62; 95% CI, -9.19 to 1.95).

Conclusions: Among patients using FLCMC, those who live alone may need additional support. Further study testing the generalizability of the findings is required.

Background: Increasing number of studies has suggested the time to first cigarette after waking (TTFC) have significant positive effect on respiratory diseases. However, few of them are focused on Chinese population. This study aims to estimate the impact of TTFC on the prevalence of chronic respiratory diseases (CRD) in Chinese elderly and explore the association in different sub-populations.

Methods: Cross-sectional data of demographic characteristics, living environment, smoking-related variables, and CRD were drawn from the Chinese Longitudinal Healthy Longevity Survey in 2018. Multivariate stepwise logistic regression analyses were conducted to examine the association of the TTFC with the prevalence of CRD.

Results: This study includes 13208 subjects aged 52 years and older, with a mean age of 85.3 years. Of them, 3779 participants are ex- or current smokers (44.9% had the TTFC ≤30 minutes, 55.1% >30 minutes) and 1503 have suffered from CRD. Compared with non-smokers, participants with TTFC ≤30 minutes seemed to have higher prevalence of CRD (OR 1.97; 95% CI, 1.65-2.35) than those with TTFC >30 minutes (OR 1.70; 95% CI, 1.44-2.00), although the difference was statistically insignificant (P_interaction=0.12). Compared with TTFC >30 minutes, TTFC ≤30 minutes could drive a higher prevalence of CRD among female participants, those aged 90 years and older, urban residents, and those ex-smokers (P_interaction<0.05).

Conclusions: Shorter TTFC relates to higher prevalences of CRD in Chinese older females, those aged 90 years and older, urban residents, and ex-smokers. Delaying TTFC might particially reduce its detrimental impact on respiratory disease in these specific subpopulations.

Mumps deafness is a serious complication of mumps and its risk factors have not been evaluated. Takagi et al. suggested that adolescents and adults have an 8.4 times higher incidence of mumps deafness than children. However, they did not validate the outcome definition of mumps and mumps deafness, and the age-related difference they observed is not the true difference in the incidence of mumps deafness.

Background: Active engagement in intellectually enriching activities reportedly lowers the risk of cognitive decline; however, few studies have examined this association, including engagement in traditional cultural activities. This study aimed to elucidate the types of cultural engagement associated with lower risk of cognitive impairment.

Methods: We examined the association between cultural engagement and cognitive impairment using Cox proportional hazards models in a cohort of 44,985 participants (20,772 males and 24,213 females) aged 65 years or older of the Japan Gerontological Evaluation Study from 2010 to 2016. Intellectual activities (eg, reading books, magazines, and/or newspapers), creative activities (eg, crafts and painting), and traditional cultural activities (eg, poetry composition [haiku], calligraphy, and tea ceremony/flower arrangement) were included among cultural engagement activities.

Results: Over a follow-up period of 6 years, incident cognitive disability was observed in 4,198 respondents (9.3%). After adjusting for potential confounders, such as depression and social support, intellectual activities were protectively associated with the risk of cognitive impairment (hazard ratio [HR] for those who read and stated that reading was their hobby, 0.75; 95% confidence interval [CI] 0.66–0.85 and HR for those who read but did not consider reading a hobby, 0.72; 95% CI, 0.65–0.80). Engagement in creative activities was also significantly correlated with lower risk of cognitive impairment (crafts: HR 0.71; 95% CI, 0.62–0.81 and painting: HR 0.80; 95% CI, 0.66–0.96). The association between traditional cultural activities and the risk of cognitive impairment was not statistically significant.

Conclusions: Engagement in intellectual and creative activities may be associated with reduced risk of dementia.

Background: Secondhand smoke (SHS) from partners is a major source of exposure for non-smoking women. However, epidemiological studies have rarely examined social factors associated with continued and indoor smoking among pregnant women’s partners.

Methods: We analyzed data on 6,091 partners of non-smoking pregnant women in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Partners’ age, education, income, workplace SHS exposure (almost never or sometimes, almost every day), and pregnant women’s smoking history (never, quit before pregnancy awareness, quit after pregnancy awareness) were used as social factors. Multiple logistic regression analyses were conducted to examine the associations of social factors with partners’ continued smoking and indoor smoking.

Results: Among 2,432 smoking partners, 2,237 continued to smoke after pregnancy awareness. Workplace SHS exposure was associated with increased risk of partners’ continued smoking: the odds ratio of workplace SHS exposure almost every day compared with almost never or sometimes was 2.08 (95% confidence interval, 1.52–2.83). Women’s quitting smoking after—but not before—pregnancy awareness was associated with decreased risk of partners’ continued smoking: the odds ratio of women’s quitting after pregnancy awareness compared with never smoking was 0.57 (95% confidence interval, 0.40–0.80). About one-third of partners who continued to smoke did so indoors. Older age, lower education, workplace SHS exposure, and women’s quitting smoking after pregnancy awareness were associated with increased risk of partners’ indoor smoking.

Conclusions: Workplace SHS exposure and pregnant women’s smoking history were associated with continued smoking and indoor smoking among partners of non-smoking pregnant women.

Background: Several studies have described an association between hemoglobin concentration and stroke; however, the influence of hemoglobin on stroke incidence has not been fully revealed. Our objective was to elucidate the association between hemoglobin concentration and stroke incidence in Japanese community residents.

Methods: In the present study, we collected the data of 12,490 subjects who were enrolled between April 1992 and July 1995 in the Jichi Medical School (JMS) Cohort Study. We excluded the subjects with a history of stroke. Hemoglobin concentrations were grouped in quartiles, and quartile 2 (Q2) was used as the reference category. A Cox proportional-hazards model was used to examine hazard ratios (HRs) and the stroke incidence rates with 95% confidence intervals (CIs).

Results: During 10.8 years of follow-up, 409 participants (212 men and 197 women) experienced a new stroke, including 97 intracerebral hemorrhages, 259 cerebral infarctions, and 52 subarachnoid hemorrhages (SAH). In sex-specific hemoglobin quartiles, the multivariate-adjusted HR was statistically significantly higher in Q1 than in Q2, and a relationship similar to a J shape was observed between all strokes (HR in Q2 vs Q1, 1.36; 95% CI, 1.02–1.83; Q3, 1.20; 95% CI, 0.87–1.64; and Q4, 1.16; 95% CI, 0.84–1.60). Furthermore, the analysis of stroke subtypes showed a statistically significantly higher multivariate-adjusted HR in Q1 than in Q2 for SAH (HR 2.61; 95% CI, 1.08–6.27).

Conclusions: A low hemoglobin concentration was associated with an increased risk of stroke, which was strongly influenced by the incidence of SAH.

Background: Sleeping pills are widely used for sleep disorders and insomnia. This population-based study aimed to evaluate the association between the use of sleeping pills and metabolic syndrome (MetS) and metabolic components in an apparently healthy Japanese cohort.

Methods: We examined baseline cross-sectional data from the JMS-II Cohort Study. The criteria for MetS and its components were based on The National Cholesterol Education Program Adult Treatment Panel III. Sleep habits including the sleep duration of the subjects and the frequency of sleeping pill use were obtained using The Pittsburgh Sleep Quality Index questionnaire. For different sleep durations, the association between sleeping pill use and MetS was assessed. Odds ratios (ORs) and their 95% confidence intervals (CIs) were estimated using multiple logistic regression models to quantify this association.

Results: Our study included 6,153 individuals (mean age, 63.8 [standard deviation 11.2] years), and 3,348 (54.4%) among them were women. The association between sleep duration and MetS was an inverted J-shaped curve among sleeping pill users and a J-shaped curve among non-users. After adjustment for various confounders, less than 6 h of sleep among sleeping pill users was associated with increased rates of MetS (<6 h, OR 3.08; 95% CI, 1.29–7.34]). The frequency of sleeping pill use in individuals with short sleep duration showed a positive association with the prevalence of MetS and its components.

Conclusions: Sleeping pill users with a short sleep duration had a 3-fold higher chance of having MetS than non-users with a short sleep duration.

Background: The hippocampus is a brain structure important for memory and cognitive function. Physical activity may help prevent hippocampal atrophy. However, few studies have measured sedentary behavior (SB) and intensity-specific physical activity using an accelerometer. This study aimed to examine the cross-sectional associations of objectively-determined SB, light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) measured by an accelerometer with hippocampal volume among community-dwelling older adults using compositional data analysis (CoDa) approach.

Methods: This cross-sectional study was part of the Neuron to Environmental Impact across Generations (NEIGE) study. A randomly recruited sample of 485 Japanese older adults (47% male; aged 65-84 years) wore tri-axial accelerometers (Omron Healthcare) for seven consecutive days in 2017. Hippocampal volume was measured with magnetic resonance imaging and the left and right hippocampal volumes were automatically segmented using FreeSurfer software. Associations of sedentary and physically active behaviors with hippocampal volume were examined with compositional linear regression analysis based on isometric log-ratio transformations of time use adjusted for potential confounding factors.

Results: The relative proportion of time spent in MVPA, compared to the other two activities, was significantly positively associated with right hippocampal volume (β: 57.1, p-value = 0.027).

However, no association existed between higher proportions of MVPA and left hippocampal volume, or between proportions of SB or LPA with either left or right hippocampal volumes.

Conclusions: The proportion of time spent in MVPA, relative to the other two activities, was significantly positively associated with right hippocampal volume. MVPA may be beneficial for maintaining hippocampal volume.

Background: While it is essential to understand how long is sufficient for return-to-work when designing paid sick-leave systems, little attempt has been done to collect cause-specific information on when and how many of sickness absentees returned to work, became unemployed, or passed away.

Methods: We studied the first sick-leave episode of ≥30 consecutive days in those ≤55 years of age during 2012–2013 among 11 Japanese private companies (n = 1209), which were followed until 2017. Overall and disease-specific cumulative incidences of return-to-work, resignations, and deaths were estimated using competing risk analysis.

Results: During the 3.5-year period (follow-up rate: 99.9%), 1014 returned to work, 167 became unemployed, and 27 died. Overall, return-to-work occurred within 1 year in 74.9% of all absentees and in 89.3% of those who successfully returned to work. Resignation occurred within 1 year in 8.7% of all absentees and in 62.9% of all subjects who resigned. According to ICD-10 chapters, the cumulative incidence of return-to-work ranged from 82.1% for mental disorders (F00-F99) to 95.3% for circulatory diseases (I00-I99). The cumulative incidence of return-to-work due to mental disorders ranged from 66.7% in schizophrenia (F20) to 95.8% in bipolar affective disorders (F31). Death was rarely observed except for cases of neoplasms (C00-D48), of which the cumulative incidence of death reached 14.2% by 1.5 years.

Conclusions: Return-to-work and resignations occurred commonly within 1 year of sick leave among long-term sickness absentees in the Japanese private companies. Our findings may assist occupational physicians and employers in developing effective social protection schemes.

Background

Little is known about the role of economic recessions in the risk of cancer. Therefore, we evaluated the impact of the severe economic recession in Finland between 1991-1994 on the incidence of all cancers and cancer subtypes among middle-age and older population.

Methods

From the Kuopio Ischemic Heart Disease Risk Factor Study (KIHD), a population-based sample of 1620 women and men aged 53-73 years were examined between 1998-2001. The cancer-free participants completed a questionnaire on the possible impact of the 1990s recession in Finland on their lives. Incident cases of cancer were obtained through record linkage with the Finnish Cancer Registry. Cox proportional hazards regression was used to estimate hazard ratios (HR) of incident cancer events after adjusting for possible confounders.

Results

A total of 1096 cancer-free participants had experienced socioeconomic hardships due to the recession at the baseline. During 20 years of follow-up, 473 participants developed cancer. After adjustment for age, baseline socioeconomic position and lifestyle factors, the risk of all cancers was 32% higher among men who experienced socioeconomic hardships compared to those who did not (HR 1.32, 95%CI, 0.99-1.75, p=0.05). Prostate-genital cancer was 71% higher among men with hardships (n=103, HR=1.71, 95%CI, 1.06-2.74, p=0.02). No association was observed between socioeconomic hardships and subsequent risk of total or any subtype of cancer among women.

Conclusions:

The 1990s economic recession was associated with increased risk of all cancers, especially prostate-genital cancer among Finnish middle-age and older men, but no association with cancer was observed in women.

Background: To investigate associations between exposure to various trajectories of severe hypoglycemic events and risk of dementia in patients with type 2 diabetes.

Methods: In 2002–2003, 677618 patients in Taiwan were newly diagnosed as having type 2 diabetes. Among them, 35720 (5.3%) experienced severe hypoglycemic events during the 3-year baseline period following diagnosis. All patients were followed from the first day after baseline period to the date of dementia diagnosis, death, or the end of 2011. A group-based trajectory model was used to classify individuals with severe hypoglycemic events during the baseline period. Cox proportional hazard models with the competing risk method were used to relate dementia risk to various severe hypoglycemia trajectories.

Results: After a median follow-up 6.70 and 6.10 years for patients with and without severe hypoglycemia at baseline, respectively, 1952 (5.5%) individuals with severe hypoglycemia and 23492 (3.7%) without developed dementia during follow-up, for incidence rates of 109.80 and 61.88 per 10000 person-years, respectively. Four groups of severe hypoglycemia trajectory were identified with a proportion of 18.06%, 33.19%, 43.25%, and 5.50%, respectively for Groups 1 to 4. Groups 3 (early manifestation but with later decrease) and 4 (early and sustained manifestation) were associated with a significantly increased risk of dementia diagnosis, with a covariate-adjusted subdistribution hazard ratio of 1.22 (95% confidence interval, 1.14–1.31) and 1.25 (95% confidence interval, 1.02–1.54), respectively.

Conclusions: Our analysis highlighted that early manifestation of severe hypoglycemic events may contribute more than does late manifestation to the risk of dementia among individuals newly diagnosed as having type 2 diabetes.

Background: The impact of weight change, physical activity, and sedentary behavior on endometrial cancer risk among the Asian population is uncertain. We investigated the association of those factors with endometrial cancer risk among Japanese women with a low body mass index level.

Methods: We performed a large-scale nationwide cohort study consisting of 33,801 female participants aged 40–79 years. The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of incident endometrial cancer.

Results: The mean body mass index of participants was 22.8 kg/m². During a median follow-up of 14.8 years, 79 participants developed endometrial cancer. After adjustment for potential confounding factors, body mass index over 23.0 kg/m² was linearly associated with the risk of endometrial cancer. The HR per 5 kg/m² increase was 1.80 (95% CI, 1.28–2.54). Weight increment ≥+5 kg since age 20 was associated with an increased risk of endometrial cancer compared to a weight change of −5 to <+5 kg (multivariable HR 1.96; 95% CI, 1.12–3.40). Compared with females who were mainly sitting at the worksite, those who were mainly standing and moving were at lower risk; the multivariable HRs were 0.79 (95% CI, 0.39–1.59) and 0.46 (95% CI, 0.22–0.97), respectively (P for trend = 0.042). Hours of physical exercise, daily walking, and TV viewing were not associated with endometrial cancer risk.

Conclusions: Overweight and weight gain were positively associated with the risk of endometrial cancer, while worksite physical activity was inversely associated with the risk.

Background: Sedentary behaviors are prevalent among children and can have a detrimental effect on their health. Little is known about the influence of parental time on children’s sedentary behavior. This study examined the association between parental working hours and children’s sedentary time.

Methods: Cross-sectional data were drawn from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE) in 2010 and 2011. Participants were 886 children aged 7–18 years and their parents. The primary outcome was self-reported sedentary time after school that comprised screen time and non-screen time. The main explanatory variable was parental working hours. We used multiple regression analysis adjusting for sociodemographic factors.

Results: Children’s mean sedentary time was 222 (standard deviation [SD], 123) min/day; 144 (SD, 108) min/day screen time and 78 (SD, 65) min/day non-screen time. Children whose mothers worked ≥20 hours/week had 28 (95% CI, 9 to 48) min/day longer sedentary time than children of homemakers (240 min/day vs 214 min/day). The longer maternal working hours, the longer sedentary time (P for trend <0.01). In contrast, children whose fathers worked ≥48 hours/week had 82 (95% CI, −156 to −7) min/day shorter sedentary time than children of non-working fathers (179 min/day vs 264 min/day). When limited to children whose fathers worked, there was no statistically significant association between children’s sedentary time and paternal working hours.

Conclusions: Children with mothers who work long hours or fathers not working tend to sit more. Supplementing the shortages in resources for childcare may be necessary among those families.

Background: To investigate the causal link between early-life exposures and long-term health consequences, we established the Tianjin Birth Cohort (TJBC), a large-scale prospective cohort in northern China.

Methods: TJBC aims to enroll 10,000 families with follow-ups from pregnancy until children’s six year-old. Pregnant women and their spouses were recruited through a three-tier antenatal healthcare system at early pregnancy, with follow-ups at mid-pregnancy, late pregnancy, delivery, 42 days after delivery, 6 months after delivery, and each year until 6 years old. Antenatal/neonatal examination, biological samples and questionnaires were collected.

Results: From August 2017 to January 2019, a total of 3,924 pregnant women have already been enrolled, and 1,697 women have given birth. We observed the prevalence of gestational diabetes mellitus as 18.1%, anemia as 20.4%, and thyroid hypofunction as 2.0%. In singleton live births, 5.6% were preterm birth (PTB), 3.7% were low birth weight, and 7.3% were macrosomia. Based on current data, we also identified maternal/paternal factors which increased the risk of PTB, including paternal age (OR 1.07; 95% CI, 1.01–1.14 for each year increase), vaginal bleeding during pregnancy (OR 2.82; 95% CI, 1.54–5.17) and maternal early-pregnancy BMI (OR 1.08; 95% CI, 1.01–1.15 for each kg/m² increase).

Conclusion: TJBC has the strength of collecting comprehensive maternal, paternal, and childhood information. With a diverse range of biological samples, we are also engaging with emerging new technologies for multi-omics research. The study would provide new insight into the causal link between macro/micro-environmental exposures of early life and short/long-term health consequences.

Background: Marital transitions are associated with adverse health events, such as mortality and cardiovascular disease. Since marital transitions (eg, becoming widowed) are unavoidable life events, it is necessary to identify modifiable intermediate outcomes. Thus, we examined the association between marital transitions and vegetable intake among middle-aged and older Japanese adults.

Methods: This longitudinal study included Japanese adults aged 40–79 years who received an annual health checkup between 2007 and 2011 (baseline) and 5 years later (follow-up). Marital transitions were classified as whether and what type of transition occurred during the 5-year period and comprised five groups: consistently married, married to widowed, married to divorced, not married to married, and remained not married. Changes in total vegetable, green and yellow vegetable, and light-colored vegetable intake from baseline to follow-up were calculated using the Food Frequency Questionnaire.

Results: Data from 4,813 participants were analyzed (mean age, 59.4 years; 44.1% women). Regarding marital transitions, 3,960 participants were classified as “consistently married,” 135 as “married to widowed,” 40 as “married to divorced,” 60 as “not married to married,” and 529 as “remained not married.” Multivariable linear regression analysis revealed that compared to consistently married, married to widowed was inversely associated with the change in total vegetable intake (β = −16.64, SE = 7.68, P = 0.030) and light-colored vegetable intake (β = −11.46, SE = 4.33, P = 0.008).

Conclusion: Our findings suggest that being widowed could result in a reduced intake of vegetables. Hence, dietary counseling according to marital situation is necessary.

Aims. As the proportion of visceral (VAT) to subcutaneous adipose tissue (SAT) may contribute to type 2 diabetes (T2D) development, we examined this relation in a cross-sectional design within the Multiethnic Cohort that includes Japanese Americans known to have high VAT. The aim was to understand how ectopic fat accumulation differs by glycemic status across ethnic groups with disparate rates of obesity, T2D, and propensity to accumulate VAT.

Methods. In 2013-16, 1,746 participants aged 69.2 (2.7) years from five ethnic groups completed questionnaires, blood collections, and whole-body DXA and abdominal MRI scans. Participants with self-reported T2D and/or medication were classified as T2D, those with fasting glucose >125 and 100-125 mg/dL as undiagnosed cases (UT2D) and prediabetes (PT2D), respectively. Using linear regression, we estimated adjusted means of adiposity measures by T2D status.

Results. Overall, 315 (18%) participants were classified as T2D, 158 (9%) as UT2D, 518 (30%) as PT2D, and 755 (43%) as normoglycemic (NG) with significant ethnic differences (p<0.0001). In fully adjusted models, VAT, VAT/SAT, and percent liver fat increased significantly from NG, PT2D, UT2D, to T2D (p<0.001). Across ethnic groups, the VAT/SAT ratio was lowest for NG participants and highest for T2D cases. Positive trends were observed in all groups except African Americans, with highest VAT/SAT in Japanese Americans.

Conclusions. These findings indicate that VAT plays an important role in T2D etiology, in particular among Japanese Americans with high levels of ectopic adipose tissue, which drives the development of T2D to a greater degree than in other ethnic groups.

Objective

Prevalence of stunting is frequently used as a marker of population-level child undernutrition. Parental height varies widely in low- and middle-income countries (LMIC) and is also a major determinant of stunting. While stunting is a useful measure of child health, with multiple causal components, removing the component attributable to parental height may in some cases be helpful to identify shortcoming in current environments.

Methods

We estimated maternal height-standardized prevalence of stunting (SPS) in 67 LMIC and parental height-SPS in 20 LMICs and compared with crude prevalence of stunting (CPS) using data on 575,767 children under-five from 67 Demographic and Health Surveys (DHS). We supplemented the DHS with population-level measures of other child health outcomes from the World Health Organization’s (WHO) Global Health Observatory and the United Nations’ Inter-Agency Group for Child Mortality Estimation. Prevalence of stunting was defined as percentage of children with height-for-age falling below -2 z-scores from the 2006 WHO growth standard.

Findings

The average CPS across countries was 27.8% (95% CI: 27.5 to 28.1) and the average SPS was 23.3% (95% CI: 23.0 to 23.6). The rank of countries according to SPS differed substantially from the rank according to CPS. Guatemala, Bangladesh, and Nepal had the biggest improvement in ranking according to SPS compared to CPS, while Gambia, Mali, and Senegal had the biggest decline in ranking. Guatemala had the largest difference between CPS and SPS with a CPS of 45.2 (95% CI: 43.7 to 46.9) and SPS of 14.1 (95% CI: 12.6 to 15.8). Senegal had the largest increase in the prevalence after standardizing maternal height, with a CPS of 28.8% (95% CI: 25.8 to 30.2) and SPS of 31.6% (95% CI: 29.5 to 33.8). SPS correlates better than CPS with other population-level measures of child health.

Conclusions

Our study suggests that CPS is sensitive to adjustment for maternal height. Maternal height, while a strong predictor of child stunting, is not amenable to policy interventions. We showed the plausibility of SPS in capturing current exposures to undernutrition and infections in children.

Background: Inflammation is thought to be a risk factor for kidney disease. However, discussion is controversial whether inflammatory status is either a cause or an outcome of chronic kidney disease. We aimed to investigate the causal relationship between high-sensitivity C-reactive protein (hs-CRP) and estimated glomerular filtration rate (eGFR) using mendelian randomization (MR) approaches.

Methods: A total of 10,521 participants of the Japan Multi-institutional Collaborative Cohort Study was analyzed in this study. We used two-sample MR approaches (the inverse-variance weighted (IVW), the weighted median (WM), and the MR-Egger method) to estimate the effect of genetically determined hs-CRP on kidney function. We selected four and three hs-CRP associated single nucleotide polymorphisms (SNPs) as two instrumental variables (IV): IV_CRP and IV_Asian, based on SNPs previously identified in European and Asian populations. IV_CRP and IV_Asian explained 3.4% and 3.9% of the variation in hs-CRP, respectively.

Results: Using the IV_CRP, genetically determined hs-CRP was not significantly associated with eGFR in the IVW and the WM methods (estimate per 1 unit increase in ln(hs-CRP), 95%CI: 0.000, –0.019 to 0.020 and –0.003, –0.019 to 0.014). For IV_Asian, we found similar results using the IVW and the WM methods (estimate, 95% CI: –0.005, –0.020 to 0.010 and –0.004, –0.020 to 0.012). The MR-Egger method also showed no causal relationships between hs-CRP and eGFR (IV_CRP: –0.008, –0.058 to 0.042; IV_Asian: 0.001, –0.036 to 0.036).

Conclusions: Our two-sample MR analyses with different IVs did not support a causal effect of hs-CRP on eGFR.

Background: Obesity and its health consequences will dominate health care systems in many countries during the next decades. However, the body mass index (BMI) optimum in relation to all-cause mortality is still a matter of debate.

Material and Methods: Data of the Vorarlberg Health Monitoring & Prevention Program (VHM&PP, 1985–2005) and data provided by the Main Association of Austrian Social Security Institutions (MAASSI, 2005–2015) were analyzed. Information was available on age, sex, smoking status, measured height and weight, and mortality. Generalized additive models were used to model mortality as a function of BMI, calendar time, age, and follow-up.

Results: In MAASSI (N = 282,216, 46.0% men), men and women were on average 2.7 years older than in VHM&PP (N = 185,361, 46.1% men). Average BMI was slightly higher in men (26.1 vs 25.7 kg/m²) but not in women (24.6 vs 24.7 kg/m²). We found an interactive effect of age and follow-up on the BMI optimum. Over age 35 years in men and 55 years in women, the BMI optimum decreased with length of follow-up. While keeping covariates fixed, BMI optimum increased slightly between 1985 and 2015 in men and women, 24.9 (95% CI, 23.9–25.9) to 26.4 (95% CI, 25.3–27.3), and 22.4 (95% CI, 21.7–23.1) to 23.3 (95% CI, 22.6–24.5) kg/m², respectively.

Conclusion: Age and length of follow-up have a pronounced effect on the BMI associated with the lowest all-cause mortality. After controlling for age and length of follow-up, the BMI optimum increased slightly over 30 years in this large study sample.

Background: The association between overweight and chronic musculoskeletal pain may vary by anatomical site and be modified by hypertension status. This study examined the associations between overweight and low back and knee pains and their effect modification by hypertension status.

Methods: We conducted a community-based cross-sectional study involving 2,845 adults (1,080 men and 1,765 women) aged 40–89 years. Chronic knee pain (CKP) and low back pain (CLBP) lasting more than 3 months were categorized into more or less severe pain. Odds ratios (ORs) and 95% confidence intervals (CIs) of the association between overweight and more or less severe CKP and CLBP were determined using logistic regression and stratified by hypertension status. Adjustment variables were age, sex, area, hypertension, smoking and drinking status, inactivity, job category, mental stress, depression, and overall CKP or CLBP.

Results: Overall, 288 (10.1%) and 631 (22.2%) adults had more and less severe CKP, respectively, and 284 (10.0%) and 830 (29.2%) had more and less severe CLBP, respectively. Overweight was associated with overall CKP and more or less severe CKP, regardless of hypertension status. Overweight was not associated with overall CLBP; its association was more pronounced for more severe CLBP. The association between overweight and more severe CLBP was evident among non-hypertensives (multivariable OR 1.72; 95% CI, 1.09–2.71); however, that between overweight and less severe CLBP was not evident (multivariable OR 1.07; 95% CI, 0.73–1.56).

Conclusions: As hypertension may attenuate the association between overweight and CLBP, we should consider hypertension status for proper management of CLBP among overweight individuals.

Background: The Japan Multi-institutional Collaborative Cohort (J-MICC) study was launched in 2005 to examine gene–environment interactions in lifestyle-related diseases, including cancers, among the Japanese. This report describes the study design and baseline profile of the study participants.

Methods: The participants of the J-MICC Study were individuals aged 35 to 69 years enrolled from respondents to study announcements in specified regions, inhabitants attending health checkup examinations provided by local governments, visitors at health checkup centers, and first-visit patients at a cancer hospital in Japan. At the time of the baseline survey, from 2005 to 2014, we obtained comprehensive information regarding demographics, education, alcohol consumption, smoking, sleeping, exercise, food intake frequency, medication and supplement use, personal and family disease history, psychological stress, and female reproductive history and collected peripheral blood samples.

Results: The baseline survey included 92,610 adults (mean age: 55.2 [standard deviation, 9.4] years, 44.1% men) from 14 study regions in 12 prefectures. The participation rate was 33.5%, with participation ranging from 19.7% to 69.8% in different study regions. The largest number of participants was in the age groups of 65–69 years for men and 60–64 years for women. There were differences in body mass index, educational attainment, alcohol consumption, smoking, and sleep duration between men and women.

Conclusions: The J-MICC Study collected lifestyle and clinical data and biospecimens from over 90,000 participants. This cohort is expected to be a valuable resource for the national and international scientific community in providing evidence to support longer healthy lives.

Background: Cancer incidence in Fukushima Prefecture, especially thyroid cancer, has been a public concern, since the Tokyo Electric Power Company Fukushima Daiichi Nuclear Power Plants accident following the Great East Japan Earthquake on March 11, 2011; however, cancer incidence for Fukushima residents before and after the accident based on a population-based cancer registry (PBCR) has not been known worldwide.

Methods: We obtained the corrected-incidence data for invasive cancers newly diagnosed from 2008 through 2015 from the Fukushima Cancer Registry. We checked data quality indicators for PBCRs to confirm comparability. We calculated age-standardized annual incidence and mortality of cancer for all-site, thyroid, and leukemia by calendar year and sex, as we did for Tochigi Prefecture and all of Japan as references for comparison. We applied joinpoint trend analysis to test an apparent trend in incidence and mortality.

Results: The corrected incidence data from the Fukushima Cancer Registry had sufficient quality comparable to other PBCRs. For the age-standardized annual incidence by sex and cancer type in Fukushima and Tochigi, we did not detect any joinpoint in trend with statistical significance. Cancer incidence gently increased from 2008 through 2015 nationwide. Incidence and mortality of cancer for Fukushima before the accident was very close to that for Tochigi.

Conclusions: We interpreted the incidence statistics of cancer for Fukushima residents from 2008 through 2015. Our results will provide fundamental statistics for subsequent researchers to assess the relationship between the disaster and cancer incidence among Fukushima residents in the long term.

Background: There have been few community-based epidemiological studies in which the prevalence of exogenous hormone use, including the use of oral contraceptives (OCs) and hormone replacement therapy (HRT), has been accurately assessed in Japan.

Methods: We have been conducting repeated surveys of participants in the Japan Nurses’ Health Study (JNHS), as a nationwide prospective cohort study, since 2001. We determined the prevalence of exogenous hormone use at baseline and during a 10-year follow-up period. A total of 15,019 female nurses participated in the JNHS follow-up cohort. We determined the prevalence of OC use in 14,839 women <60 years of age at baseline and the prevalence of HRT use in 7,915 women, excluding premenopausal women, at the last time they answered a questionnaire. The duration of HRT use was estimated using the Kaplan-Meier method.

Results: Six percent of the participants used OCs. The proportion of HRT users who stopped HRT before the baseline survey, the proportion of women using HRT during the follow-up period, and the proportion of all of the participants who had used HRT were 3.2%, 10.6%, and 13.8%, respectively. The median duration of HRT use was 2 years.

Conclusions: The lifetime prevalences of exogenous hormone use during this prospective study conducted in Japanese nurses were 6.0% for OCs and 13.8% for HRT. The information obtained in this study will be useful for clarification of the association between exogenous estrogen exposure and estrogen-related diseases as future research.

Background: Limited epidemiological evidence has suggested a positive relationship between night shift work and the risk of cancer. Herein, we investigated the prospective association between different forms of work schedule and the risk of numerous cancers and all-cause cancer among Japanese men and women.

Methods: This cohort study included 45,390 working men and women aged 40–79 years and registered in the Japan Collaborative Cohort Study (JACC Study). The Cox proportional hazards models were used to calculate the hazard ratios (HRs) and their 95% confidence intervals (CIs) for incident cancer among those who reported engagement in night work and rotating shift work for their longest occupations compared with day work.

Results: Within a median follow-up duration of 14.2 years, 2,283 (9.4%) men and 1,309 (4.5%) women developed cancer. Among men, rotating shift work was significantly associated with increased risk of esophageal cancer (HR 2.47; 95% CI, 1.42–4.31) and decreased risk of liver cancer (HR 0.54; 95% CI, 0.30–0.98). Also, rotating shift work tended to be associated with the increased risk of prostate cancer (HR 1.42; 95% CI, 0.95–2.12). Night work and rotating shift work were not related to the risk of all-cause cancer in either sex.

Conclusion: Rotating shift work might contribute to the increased risk of esophageal cancer and prostate cancer and the decreased risk of liver cancer among Japanese men.