Atsuhiko Ota

Psychosocial job characteristics and insomnia: A prospective cohort study using the Demand-Control-Support (DCS) and Effort–Reward Imbalance (ERI) job stress models

OBJECTIVE To examine the prospective effects of psychosocial job characteristics evaluated with the Demand-Control-Support (DCS) and Effort-Reward Imbalance (ERI) models on insomnia. METHODS A prospective cohort study with a two-year observation was performed. The subjects were 1022 middle-aged (>or= 39 years) Japanese workers. The following associations were analyzed: high job strain, low social support, effort-reward imbalance, and overcommitment to work at the baseline with self-reported persistence and future onset of insomnia. RESULTS Among those who were insomniacs at the baseline (N=292), low social support [adjusted odds ratio (95% CI): 2.00 (1.18, 3.40)] and effort-reward imbalance [2.40 (1.13, 5.10)] at the baseline had a significant relationship to insomnia at the follow-up. Among those who were not insomniacs at the baseline (N=730), overcommitment to work [1.75 (1.16, 2.66)] and high job strain [1.72 (1.06, 2.79)] at the baseline were associated with insomnia at follow-up. CONCLUSIONS Prospective effects of psychosocial job characteristics on insomnia differed between its persistence and future onset. Proportionate reward for work effort and sufficient support at work assist recovery from insomnia, while overcommitment to work and high job strain cause future onset of insomnia.

Relationship of job stress with nicotine dependence of smokers--a cross-sectional study of female nurses in a general hospital.

The degree of nicotine dependence is an important predictor of successful cessation of smoking among smokers. Some investigators reported a possible relationship between reducing job stress and successful smoking cessation . This may be attributable to the effect of job stress on nicotine dependence. That is, high levels of job stress could produce and/or maintain high levels of nicotine dependence among smokers, and could result in difficulty in smoking cessation. If this hypothesis were true, workplace smoking cessation programs should take account of the influence of job stress on nicotine dependence, and measures to curb nicotine dependence resulting from coping with job stress should be introduced into the programs. There are, however, few reports that deal with the influence of job stress on the nicotine dependence of smokers in the workplace. Tobacco dependence is a multi-dimensional addiction that includes psychological and behavioral aspects of dependence on smoking or nicotine as well as physiological dependence 7, . It is important to measure various aspects of nicotine dependence separately. Two short and easyto-apply self-reporting questionnaires are frequently used to screen for nicotine dependence. They are the Fagerstrom Test of Nicotine Dependence (FTND) 2) and the Tobacco Dependence Screener (TDS). They evaluate different aspects of nicotine dependence. The FTND assesses the physiological aspects of nicotine dependence and is positively associated with the number of cigarettes smoked per day and the plasma level of nicotine and cotinine 2, . On the other hand, the TDS is closely correlated with the psychological aspects of nicotine dependence; a TDS score of 6 or greater indicates nicotine dependence diagnosed according to the International Classification of Diseases, 10 revision (ICD-10), and the Diagnostic and Statistical Manual of Mental Disorders, third edition revised (DSM-III-R), with sensitivity values of 95% and 79%, and specificity values of 81% and 66%, respectively. In addition, previous studies reported a poor concordance between the FTND score and the DSM-III-R diagnosis; Moolchan et al. showed that the highest kappa (at a cutoff of the FTND=7 or greater) was .205. The objective of this cross-sectional study was to examine the relationship between perceived job stress and nicotine dependence assessed with two self-reporting questionnaires (i.e., the FTND and TDS) completed by workers who smoked tobacco. Nurses were chosen as subjects in this study. They are health professionals with a reportedly high prevalence of smoking ; in addition, they are expected to act as role models for patients with a desire to quit smoking. Elkind has reported that certain peculiar characteristics associated with the hospital environment and the nursing process may contribute to the smoking habits of nurses. Nurses deserve special attention in developing a smoking cessation program which considers the influence of job stress on the smoking habit.

Psychosocial job characteristics and smoking cessation: A prospective cohort study using the Demand-Control-Support and Effort-Reward Imbalance job stress models

INTRODUCTION A prospective cohort study was conducted to examine the effects of psychosocial job characteristics on smoking cessation. Previous studies have failed to indicate consistently that psychosocial job characteristics predicted smoking cessation. Using the Demand-Control-Support (DCS) and Effort-Reward Imbalance (ERI) models simultaneously, we assessed psychosocial job characteristics more comprehensively than did previous researchers. METHODS This study was performed using a population derived from a corporate manufacturing group in Japan. At the baseline, 579 (41%) of 1,423 middle-aged (> or = 39 years) male employees were smokers. These male smokers were considered as the study subjects and were asked to undergo a follow-up examination after 2 years. Prospective analysis of the relationship between psychosocial job characteristics at the baseline and smoking cessation at the follow-up was performed. Job strain, social support, effort-reward imbalance, and overcommitment to work were assessed as psychosocial job characteristic factors. RESULTS The smoking cessation rate among the study subjects at the follow-up was recorded as 5% (31/579). No psychosocial job characteristic factors at the baseline were significantly related to smoking cessation at the follow-up. DISCUSSION Even with the simultaneous use of the DCS and ERI models, we did not find positive results in terms of the prospective effects of psychosocial job characteristics on smoking cessation. Considering the results of relevant previous studies and those of the present study, we suppose that psychosocial job characteristics could have essentially little effect on smoking cessation.

Differential Effects of Power Rehabilitation on Physical Performance and Higher-level Functional Capacity among Community-dwelling Older Adults with a Slight Degree of Frailty

BACKGROUND Evidence is still insufficient regarding the effects of Power Rehabilitation (PR) on physical performance and higher-level functional capacity of community-dwelling frail elderly people. METHODS This nonrandomized controlled interventional trial consisted of 46 community-dwelling elderly individuals with light levels of long-term care needs. They were allocated to the intervention (I-group, n = 24) and control (C-group, n = 22) groups. Of them, 32 persons (17 in the l-group; 15 in the C-group) (median age, 77 years; sex, 28% male) completed the study. The l-group subjects underwent PR twice a week for 12 weeks. The outcomes were physical performance (muscle strength, balance, flexibility, and mobility) and higher-level functional capacity as evaluated by the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) and the level of long-term care need as certified by the public long-term care insurance. RESULTS The l-group demonstrated a significant improvement in the measured value of the timed up-and-go test (median change, a decrease of 4.4 seconds versus a decrease of 0.2 seconds, p = 0.033) and the timed 10-meter walk (a decrease of 3.0 seconds versus an increase of 0.2 seconds, p = 0.007) in comparison with the C-group. No significant change was observed in the TMIG-IC scores or in the level of long-term care need in the l-group. CONCLUSION PR improved mobility of community-dwelling frail elderly people; however, such improvement did not translate into higher-level functional capacity. Our findings demonstrate the difficulty in transferring the positive effects associated with PR into an improvement in higher-level functional capacity.

The Effort-reward Imbalance work-stress model and daytime salivary cortisol and dehydroepiandrosterone (DHEA) among Japanese women

We examined the influence of work-related effort–reward imbalance and overcommitment to work (OC), as derived from Siegrists Effort–Reward Imbalance (ERI) model, on the hypothalamic–pituitary–adrenocortical (HPA) axis. We hypothesized that, among healthy workers, both cortisol and dehydroepiandrosterone (DHEA) secretion would be increased by effort–reward imbalance and OC and, as a result, cortisol-to-DHEA ratio (C/D ratio) would not differ by effort–reward imbalance or OC. The subjects were 115 healthy female nursery school teachers. Salivary cortisol, DHEA, and C/D ratio were used as indexes of HPA activity. Mixed-model analyses of variance revealed that neither the interaction between the ERI model indicators (i.e., effort, reward, effort-to-reward ratio, and OC) and the series of measurement times (9:00, 12:00, and 15:00) nor the main effect of the ERI model indicators was significant for daytime salivary cortisol, DHEA, or C/D ratio. Multiple linear regression analyses indicated that none of the ERI model indicators was significantly associated with area under the curve of daytime salivary cortisol, DHEA, or C/D ratio. We found that effort, reward, effort–reward imbalance, and OC had little influence on daytime variation patterns, levels, or amounts of salivary HPA-axis-related hormones. Thus, our hypotheses were not supported.

Nicotine dependence and smoking cessation after hospital discharge among inpatients with coronary heart attacks

This study focuses on the predictability of two alternative questionnaires for nicotine dependence, i.e., the Fagerstrom Tolerance Questionnaire (FTQ) and the Tobacco Dependence Screener (TDS), each of which represents a different aspect of dependence, among patients with coronary heart disease (CHD). Twenty-nine male inpatients that had been newly diagnosed as CHD were followed up for 30 weeks after hospital discharge. The baseline information included age, number of cigarettes per day, years of smoking, disease type (angina pectoris [AP] or acute myocardial infarction [AMI), whether they had received a briefing on smoking cessation, the FTQ, and the TDS. At 30 weeks after hospital discharge, 19 (66%) were abstainers. The group with a high TDS score (of 6 or greater) was significantly less likely to quit smoking than the group with a low TDS score (p=0.046). The FTQ score was not significantly different between the abstainers and non-abstainers. The subjects with AP were significantly less likely to quit smoking than those with AMI (p=0.021). Multiple logistic regression analysis showed that belonging to the high-TDS group and being diagnosed as AP were significantly associated with failure in smoking cessation (p<0.05). The present study suggests that the TDS may have higher predictability than the FTQ concerning smoking cessation among CHD inpatients.

Prospective study of seaweed consumption and thyroid cancer incidence in women: the Japan collaborative cohort study.

Excess intake of iodine is a suspected risk factor for thyroid cancer. Previous epidemiological research from Japan reported that daily intake of seaweed was associated with a four-fold higher risk in postmenopausal women, whereas others reported a null association. A major source of iodine intake in Japan is from edible seaweeds, and it is reported to be among the highest in the world. We examined the association between seaweed intake frequency and the risk of thyroid cancer in women in the Japan Collaborative Cohort Study followed from 1988 to 2009. Seaweed intake, together with other lifestyle-related information was collected using a self-administered questionnaire at baseline. Seaweed intake frequency was categorized as follows: 1–2 times/week or less, 3–4 times/week, and almost daily. Hazard ratios and the 95% confidence intervals of thyroid cancer incidence according to seaweed intake frequency were estimated using Cox proportional hazards regression. During 447 876 person-years of follow-up (n=35 687), 94 new cases of thyroid cancer were identified. The crude incidence rate was 20.9 per 100 000 person-years. The hazard ratio of thyroid cancer in women who consumed seaweed daily compared with women who ate it 1–2 times/week or less was 1.15 (95% confidence interval: 0.69–1.90, P for trend=0.59). Further analyses did not indicate any association between seaweed intake and the risk of thyroid cancer on statistically adjusting for potential confounding variables as well as on stratification by menopausal status. The present study did not find an association between seaweed intake and thyroid cancer incidence in premenopausal or in postmenopausal women.

Psychological job strain, social support at work and daytime secretion of dehydroepiandrosterone (DHEA) in healthy female employees: cross-sectional analyses

Evidence is limited concerning the influences of high psychological job strain and low social support at work on daytime secretion of dehydroepiandrosterone (DHEA), which demonstrates anti-cortisol effects. We carried out a cross-sectional study to examine the associations of job strain and social support with daytime secretion amounts of DHEA and cortisol and daytime variation of the cortisol-to-DHEA ratio (C/D ratio) in healthy female workers. Study subjects comprised 115 healthy female nursery school teachers. Area under the curve with respect to ground (AUCG) of salivary DHEA, cortisol and C/D ratio was calculated for estimation of daytime secretion and variation. Social support scores were negatively associated with daytime DHEA secretion (standardized partial regression coefficient = −0.343, P < 0.001 by multiple linear regression analysis). This association remained significant when daytime cortisol secretion was additionally adjusted. Social support was not associated with daytime variation of the C/D ratio. Significant association between social support and daytime cortisol secretion was not confirmed. Job strain was not associated with DHEA, cortisol or the C/D ratio. In summary, we found that daytime DHEA secretion was increased in healthy workers with low social support, perhaps independent of daytime cortisol secretion.

Depictions of smoking in recent high-grossing Japanese movies

Some have argued that depictions of smoking in movies are factors that trigger the initiation of adolescent smoking.1–6 Previous studies on this topic were carried out mostly in the United States. There are few data on the depiction of smoking in Japanese movies. In Japan, smoking is highly prevalent among adolescents and adults.7 8 In this study, we examined the frequency with which smoking is depicted in recent high-grossing Japanese movies. The 10 highest-grossing Japanese movies in each year from 2000 to 2006 were viewed. The box-office receipts were based on the records of the Motion Picture Association …

The association between objective measures of residence and worksite neighborhood environment, and self-reported leisure-time physical activities: The Aichi Workers' Cohort Study

The possible effects of a neighborhoods built environment on physical activity have not been studied in Asian countries as much as in Western countries. The present study cross-sectionally examined the relationship between geographic information system (GIS) measured residence and worksite neighborhood walkability, and the number of parks/green spaces and sports facilities within a 1 km radius of home and workplace, with self-reported leisure-time habitual (3–4 times per week or more) walking and moderate-to-vigorous intensity habitual exercise among local government workers aged 18 to 64 years living in an urban-suburban area of Aichi, Japan in 2013. A single-level binomial regression model was used to estimate the multivariable odds ratios (ORs) and 95% confidence intervals (95% CIs). Of the 1959 male and 884 female participants, 288 (15%) and 141 (16%) reported habitual walking, respectively, and 18% and 17% reported habitual exercise, respectively. Compared with women who resided in neighborhood with a walkability index of 4–30, those living in an area with that of 35–40 were significantly more likely to engage in leisure-time habitual exercise (multivariable OR: 1.70, 95% CI: 1.08–2.68). Marginally significant positive associations were found between leisure-time habitual exercise and the residential neighborhoods number of parks/green spaces among women, as well as the number of sports facilities among men. In conclusion, a residential neighborhood environment characterized by higher walkability may contribute to the initiation or maintenance of moderate-to-vigorous intensity leisure-time exercise among working women living in an urban-suburban area of Japan.