Michikazu Sekine

Associations of job strain and working overtime with adverse health behaviors and obesity: evidence from the Whitehall II Study, Helsinki Health Study, and the Japanese Civil Servants Study

Adverse health behaviors and obesity are key determinants of major chronic diseases. Evidence on work-related determinants of these behavioral risk factors is inconclusive, and comparative studies are especially lacking. We aimed to examine the associations between job strain, working overtime, adverse health behaviors, and obesity among 45-60-year-old white-collar employees of the Whitehall II Study from London (n=3,397), Helsinki Health Study (n=6,070), and the Japanese Civil Servants Study (n=2,213). Comparable data from all three cohorts were pooled, and logistic regression analysis was used, stratified by cohort and sex. Models were adjusted for age, occupational class, and marital status. Outcomes were unhealthy food habits, physical inactivity, heavy drinking, smoking, and obesity. In London, men reporting passive work were more likely to be physically inactive. A similar association was repeated among women in Helsinki. Additionally, high job strain was associated with physical inactivity among men in London and women in Helsinki. In London, women reporting passive work were less likely to be heavy drinkers and smokers. In Japan, men working overtime reported less smoking, whereas those with high job strain were more likely to smoke. Among men in Helsinki the association between working overtime and non-smoking was also suggested, but it reached statistical significance in the age-adjusted model only. Obesity was associated with working overtime among women in London. In conclusion, job strain and working overtime had some, albeit mostly weak and inconsistent, associations with adverse health behaviors and obesity in these middle-aged white-collar employee cohorts from Britain, Finland, and Japan.

Analysis of factors that influence body mass index from ages 3 to 6 years: A study based on the Toyama cohort study

Abstract Background : The aim of the present study was to elucidate both environmental and behavioral factors that influence body mass index (BMI, kg/m2) among Japanese children from ages 3−6.

Morning-evening preference: sleep pattern spectrum and lifestyle habits among Japanese junior high school pupils.

We surveyed the sleep‐wake patterns and lifestyle habits in a sample of Japanese first to third year junior high school children (n=638, age 12 to 15 yrs), of whom 29.3% were evening type, 64.1% intermediate type, and 6.6% morning type in preference. The morningness‐eveningness (M‐E) score was lower (more evening typed), 16.1 vs. 15.4 in first compared to third year students. There were significant gender differences, with girls showing a greater evening preference. Evening preference was associated with longer sleep latency, shortened sleep duration during schooldays and weekends, bad morning feeling, and episodes of daytime sleepiness. In contrast, morning preference was associated with higher sleep drive and better sleep‐wake parameters and lifestyle habits. Our results suggest the morning preference should be promoted among junior high school children to increase the likelihood of more regular sleep‐wake patterns and lifestyle habits.

Lifestyle and Overweight Among Japanese Adolescents : The Toyama Birth Cohort Study

Objective To investigate the effects of lifestyle factors on overweight among Japanese adolescents. Methods We studied 5753 junior high school students (2842 boys and 2911 girls) aged 12 to 13 years. The students were residents of Toyama prefecture, Japan and completed a questionnaire about their height, weight, and lifestyle factors, in June and July 2002. Subjects with a body-mass index (BMI) higher than age- and sex-specific cut-off points were defined as obese. Parental overweight was defined as a BMI of 25 or higher. Logistic regression analysis was used to examine associations between lifestyle factors and overweight. Results Skipping breakfast, eating quickly, excessive eating, physical inactivity, and long hours of TV watching were positively and significantly associated with overweight in both sexes. There was a negative association between snacking and overweight in girls (P < 0.001); no such association was found in boys (P > 0.05). Nighttime snacking was negatively associated with overweight in boys and girls (P < 0.05). Extended video game playing (≥2 hours; OR = 2.00, P = 0.012) and short sleep duration (<7 hours; OR = 1.81, P = 0.004) were significantly associated with overweight in girls only. The respective risks of overweight that derived from the subjects’ fathers and mothers were 2.0 and 2.5 times, respectively, in boys and 1.9 and 3.0 times in girls. Conclusions Parental overweight, skipping breakfast, eating quickly, excessive eating, long hours of TV watching, long hours of video game playing, physical inactivity, and short sleep duration were associated with adolescent overweight. Furthermore, there were significant negative associations between adolescent overweight and snacking in girls and nighttime snacking in both sexes.

Socioeconomic Inequalities in Physical and Mental Functioning of British, Finnish, and Japanese Civil Servants: Role of Job Demand, Control, and Work Hours

In general, women report more physical and mental symptoms than men. International comparisons of countries with different welfare state regimes may provide further understanding of the social determinants of sex inequalities in health. This study aims to evaluate (1) whether there are sex inequalities in health functioning as measured by the Short Form 36 (SF-36), and (2) whether work characteristics contribute to the sex inequalities in health among employees from Britain, Finland, and Japan, representing liberal, social democratic, and conservative welfare state regimes, respectively. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40-60 years. We found that more women than men tended to have disadvantaged work characteristics (i.e. low employment grade, low job control, high job demands, and long work hours) but such sex differences were relatively smaller among employees from Finland, where more gender equal policies exist than Britain and Japan. The age-adjusted odds ratio (OR) of women for poor physical functioning was the largest for British women (OR = 2.08), followed by for Japanese women (OR = 1.72), and then for Finnish women (OR = 1.51). The age-adjusted OR of women for poor mental functioning was the largest for Japanese women (OR = 1.91), followed by for British women (OR = 1.45), and then for Finnish women (OR = 1.07). Thus, sex differences in physical and mental health was the smallest in the Finnish population. The larger the sex differences in work characteristics, the larger the sex differences in health and the reduction in the sex differences in health after adjustment for work characteristics. These results suggest that egalitarian and gender equal policies may contribute to smaller sex differences in health, through smaller differences in disadvantaged work characteristics between men and women.

Social class differences in health behaviours among employees from Britain, Finland and Japan: The influence of psychosocial factors

This study aims to examine social class differences in smoking, heavy drinking, unhealthy food habits, physical inactivity and obesity, and work-related psychosocial factors as explanations for these differences. This is done by comparing employee cohorts from Britain, Finland and Japan. Social class differences in health behaviours are found in the two western European countries, but not in Japan. The studied psychosocial factors related to work, work-family interface and social relationships did not explain the found class differences in health behaviours.

Association of Sleep Quality and Free Time Leisure Activities in Japanese and British Civil Servants

Association of Sleep Quality and Free Time Leisure Activities in Japanese and British Civil Servants: Ali Nasermoaddeli, et al. Department of Welfare Promotion and Epidemiology, Toyama Medical and Pharmaceutical University—Sleep disturbance as a pervasive health problem can directly affect the physical and psychological well‐being of individuals. Factors that positively relate to sleep quality can therefore improve healthy functioning. We examined whether leisure time activities are associated with sleep quality in two culturally different samples of civil servants. In this cross‐sectional study we evaluated 1,682 Japanese, in Toyama prefecture (T) city, and 6,914 British civil servants from the Whitehall II study undertaken in London. The Japanese version of Pittsburgh sleep quality index (PSQI‐J) was used in T city and Jenkins’ sleep problem scale was used in the Whitehall II study. Setting a validated cut‐off point of 5.5 for the PSQI‐J global score and the upper tertile point for the Jenkins’ sleep problem scale, we conducted logistic regression analysis to assess the association between leisure time activities and sleep quality. In both populations, those who participated in voluntary activities in clubs or organizations were significantly less likely to have poor sleep quality with Odds ratios (OR) and 95% confidence intervals (95%CI) of 0.73 (95%CI; 0.56–0.97) and 0.85 (95%CI; 0.76–0.95) in Japanese and British civil servants, respectively. Similar findings were apparent for visiting friends and relatives (ORs 0.60 (95%CI; 0.46–0.80) and 0.71 (95%CI; 0.56–0.90) for Japanese and British subjects, respectively). Our findings suggest that engagement in social leisure activities is associated with better sleep quality and consequently better general well‐being.

Job Strain and Sleep Quality in Japanese Civil Servants with Special Reference to Sense of Coherence

Job Strain and Sleep Quality in Japanese Civil Servants with Special Reference to Sense of Coherence: Ali Nasermoaddeli, et al. Department of Welfare Promotion and Epidemiology, Toyama Medical and Pharmaceutical University—The combination of poor sleep quality and high job strain may provoke poor health status. Meanwhile, a sense of coherence (SOC), composed of comprehensibility, manageability and meaningfulness has been associated with adoptive measures in responding to life stress. In this study we investigated the impact of job strain on the sleep quality in civil servants and the extent to which SOC affects their sleep quality. In this cross‐sectional study we evaluated 1682 civil servants working in departments related to the municipality of T city in Toyama prefecture, Japan, in the spring of 2001. Using the validated Japanese versions of Pittsburgh sleep quality index (PSQI‐J), SOC‐13 and a self‐reported questionnaire providing information on psychosocial stress in the workplace, we conducted logistic regression analysis to assess the impact of low and high SOC (differentiating by the median score) on sleep quality in different levels of job strain. Using a cut‐off point of 5.5 in the PSQI‐ J global score, high job strain subjects were less likely to have good sleep quality (Odds ratio=0.62; 95% confidence interval: 0.44‐0.86) compared with those with lower levels of strain at the workplace after adjusting for potential confounders. Compared with high job strain/low SOC subjects, high job strain/high SOC civil servants were likely to have better sleep quality (Odds ratio=2.12; 95%CI: 1.08‐4.19) after adjusting for age, sex, employment category, level of education and negative affectivity. Increasing psychological stress at the workplace may decrease sleep quality in Japanese civil servants, but a high sense of coherence may attenuate the adverse impact of job strain on sleep quality.

Obesity and cardiac autonomic nerve activity in healthy children: Results of the toyama birth cohort study

ObjectivesTo determine the relationship between obesity and cardiac autonomic nerve activity in healthy children.Methods16 healthy male children comprising of 9 nonobese and 7 obese subjects (body mass index > 19.1 kg/m2) aged 8–9 years were selected. Electrocardiograms were measured for 10 min. under controlled ventilation (0.25 Hz) in the supine position. Consecutive 256-second RR interval data were transformed by the Fast Fourier Transform method into power spectral data. Very low frequency (VLF; 0.003–0.04 Hz), low frequency (LF; 0.04–0.15Hz), high frequency (HF; 0.15–0.40Hz), and total power (TP; 0.003–0.40Hz) were calculated and transformed into a natural logarithm (In). Normalized units (nu) were also calculated as follows: LFnu=LF/(TP-VLF)x100. HFnu=HF/(TP-VLF)x100. Low/high-frequency ratio (LHR) was calculated as LF divided by HF. Unpaired t test was performed to compare the 2 groups.ResultsTP In and HFnu, reflecting cardiac parasympathetic nerve activity, in obese children were significantly lower than those in nonobese children. In contrast, LFnu and LHF, reflecting cardiac sympathetic nerve activity, in obese children were significantly higher than those in nonobese children.ConclusionsThese findings suggest that obese children have higher sympathetic nerve activity and lower parasympathetic nerve activity than nonobese children.

Association of Smoking Behavior and Socio-Demographic Factors, Work, Lifestyle and Mental Health of Japanese Civil Servants

Association of Smoking Behavior and Socio‐Demographic Factors, Work, Lifestyle and Mental Health of Japanese Civil Servants: Lizhen Hu, et al. Department of Welfare Promotion and Epidemiology, Graduate School of Medical Sciences, University of Toyama—Few studies have examined the individual and social impact of smoking behavior in the Japanese population. The purpose of this study was to clarify the association between smoking behavior and socio‐demographic factors, lifestyle, mental health and work characteristics of Japanese civil servants. A self‐administered questionnaire survey of 1,439 employees (821 men and 618 women) aged 20–64 yr was conducted in a local government department in 2001. The questionnaire included items on socio‐demographic factors, education level, grade of employment, lifestyle, affect balance scale, and work characteristics. Smoking status was divided into current smoker, ex‐smoker and never smoked. Multiple logistic regression analysis was performed to evaluate the relationship between smoking and the other items. Men presented a higher smoking prevalence rate than women (53.1% vs. 4.9%). In men, a strong relationship between current smoker and advanced age (40 yr or older), low education level, less physical activity, irregular breakfast and negative affect balance was found. Among men with a low education, the prevalence of smoking cessation was significantly lower in comparison to men with a high education. In women, being young (20–29 yr), unmarried (single or other), having a hobby, and irregular breakfast were associated with smoking behavior. Furthermore, smoking cessation was significantly associated with having a hobby and negative affect balance. The above results suggest that socio‐demographic, lifestyle and mental health characteristics are independently associated with current smoking. These factors should be considered in smoking cessation policies as program components.