生活習慣病に潜む心理社会的ストレス(パネルディスカッション : 生活習慣病と心身医学,2007年,第48回日本心身医学会総会(福岡))  [in Japanese] Psychosocial Stress in Diseases Related to Lifestyles(Panel Discussion : Diseases Related to Lifestyles and Psychosomatic Medicine)  [in Japanese]

心理社会的ストレスは生活習慣病の発症や途中経過に深く関与している.日本で策定されたメタボリックシンドロームの診断基準は,各項目が健康診断で簡便に測定でき,動脈硬化を原因とする心血管疾患を明確なエンドポイントにしているので,生活習慣の予防的戦略が立てやすくなった.今こそ公衆衛生学と臨床医学が一致団結して生活習慣病に取り組むチャンスであり,心身医学はその牽引役になりえる.パネルディスカッションでは心理社会的ストレスの1つとして職場ストレスに注目した.任期制雇用研究者が定年制雇用研究者と比べ,労働時間が長く疲労を頻繁に自覚していることを明らかにした.また5年間のコホート調査により,任期制雇用研究者が定年制雇用研究者と比べ,総コレステロールを経年的に増加させてHDLコレステロールを経年的に減少させる可能性を示した.生活習慣の予防のためには,個人ベースだけのアプローチだけでなく,職域を含む集団ベースのアプローチも重要となる.

Background : In Japan, heart disease and cerebral vascular disease are the second and third leading causes of death, respectively, following neoplasm. Unhealthy lifestyles exacerbate risk factors for cardiovascular disease, which may be closely associated with psychosocial stress. Stress is the term used to define the body's physiological and/or psychological reaction to circumstances that require behavioral adjustment. According to the Japanese National Survey of Health in 2004, 49% of those 12 years or older reported experiencing stress in their daily lives. In this survey, the subjects answered "yes" if they perceived stress in any of 28 domains including work, family and neighborhood relations as well as living-, social-, financial-, and health-related situations. Concerning a Japanese working population, overtime work and a variety of work-related stresses have been reported to increase cardiovascular risks such as hypertension and dyslipidemia. The risks may be apparent under the psychosocial pressure of unstable employment. The aim of this study was to assess the impact of term-limited employment systems on changes in cardiovascular risks and health-related lifestyles, using data from annual health examinations over a 5-year period. Methods : The subjects were 554 male researchers (375 term-limited and 179 tenure-track, aged 33 to 42 years) participating in annual health examinations at an institute during 2001 to 2005. The outcomes were physical factors (body mass index, blood pressure, serum cholesterol, and blood hemoglobin Ale) and behavioral factors (smoking, alcohol consumption, exercise, breakfast intake, sleep, and working hours). Multiple regression analyses of a random effects model were performed, including employment status (term-limited or tenure-track), year of examination, age, and interaction of employment status and year of examination as independent variables. Results : Term-limited status was associated with an annual increase in the serum total cholesterol level (p=0.013) and an annual decrease in the high-density-lipoprotein level (p=0.002). No significant differences were found between the term-limited and tenure-track researchers in annual changes of health-related behaviors, but the termlimited researchers tended to work more hours (p=0.020), compared with the tenure-track researchers. Conclusions : These results imply that health-care practitioners in the workplace need to pay attention to the cardiovascular risks of term-limited employees in association with overtime work. According to a guideline of the "Comprehensive Program for the Prevention of Health Impairment Due to Overwork (2002)" published by the Japanese Ministry of Health, Labour and Welfare, Japanese employers are required to limit extra working hours to less than 45 per month. It is important to monitor the health status of term-limited employees carefully, paying particular attention to excessive overwork based on the published guidelines. This approach could reduce the risks of cardio-vascular diseases in the workplace, and further studies are needed to focus on the health of term-limited employees.