Gender differences in the relationship between self-rated health (SRH) and 6-year mortality risks among the elderly in Japan

The purpose of this study was to investigate the relationship between SRH and mortality among 784 non-institutionalized community-living elderly in Japan from 1995 to 2001. The data were collected by face-to-face interviews. The direct effect was estimated by the ratio of regression coefficient of two adjacent models (full model entered all covariates to total effect of SRH), and composed of the direct and indirect effect. Cox analysis stratified by gender was employed to examine the relationship between SRH and mortality. At follow-up in 2001, 148 (18.9%) died, and 636 (81.1%) were alive. Mortality rates were significantly increased with worsening SRH responses for men, but not for women. Men had a significant dose–response association between SRH and mortality, in comparison with fair or poor SRH, the odds ratio for good SRH were multiplied by 0.63 and 0.48, respectively. The magnitude of the direct effect of SRH on mortality was much larger in men (95.7%) than in women (52.5%). These findings suggest that SRH may be more strongly and directly associated with mortality in men, compared to women. Further researches are needed to explore the relationship between the changes in SRH and mortality among elderly people.