Relationship between life style and mortality among atomic bomb survivors
METHODS: Items in the questionnaire included distance of the exposed place from the hypocenter, smoking, drinking, exercise, health checkup and mental health conditions. We dichotomized the distance from the hypocenter: less than 2 km, and 2 km or over. Mental health conditions were assessed by 12-item version of General Health Questionnaire. In 13,048 survivors finally remained for the analysis, 3,448 died from 1 April 2003 through 31 March 2012; 1,138 died from cancer, 899 from circulatory system diseases and 1,351 from other diseases. We analyzed the effects of smoking, drinking, exercise, health checkup and mental health conditions on mortality separately using Cox proportional hazard model after adjusting for sex, age and the dichotomized distance from the hypocenter.
RESULTS: In the comparison of survivors without and with exercise, the hazard of death from cancer in the former group was 1.24-fold of that in the latter group (95% confidence interval: 1.10-1.40), the hazard of death from circulatory system in the former group was 1.50-fold of that in the latter group (1.30-1.72), and the hazard of death from other causes in the former group was 1.53-fold of that in the latter group (1.37-1.72).Similarly, in the comparison of survivors without and with health checkup, the hazard of death from cancer in the former group was 1.16-fold of that in the latter group (0.96-1.41), the hazard of death from circulatory system in the former group was 1.50-fold of that in the latter group (1.25-1.82), and the hazard of death from other causes in the former group was 1.37-fold of that in the latter group (1.17-1.60).
CONCLUSIONS: More detailed survey is needed to confirm the present results.