Health-related Quality of Life among Community-dwelling Elderly People in the General Populations of the US and Japan

Background Japanese live longer than Americans, but whether elderly Japanese enjoy better health-related quality of life (HRQOL) than elderly Americans is unknown. Objective To compare HRQOL between community-dwelling elderly Japanese and Americans using population data. Design, Setting, and Participants Retrospective, cross-sectional study using nationwide survey data of 706 US and 491 Japanese subjects aged 65 years or above. Main outcome measures The 36-Item Short-Form Health Survey. Results Elderly Japanese had higher physical-related HRQOL scores (physical functioning, role-physical, bodily pain, vitality) and social functioning than elderly Americans. The disparity of physical functioning scores between the two populations was greater in the higher-aged groups. Medical conditions were surveyed using a self-report questionnaire. More than 76% of elderly Americans reported having two or more medical conditions compared with 39% of Japanese. Only 8.3% of elderly Americans reported having no medical condition, compared with 28% of Japanese. Multivariate analyses suggest that the number of medical conditions is the most important independent predictor for physical functioning scores. In addition, mental health-related HRQOL scores (mental health, general health perceptions, and role-emotional) were lower in Japanese than in the Americans. Conclusions Community-dwelling elderly Americans had lower physical functioning and more comorbid conditions than similarly aged Japanese.