Subjective Well-Being and Active Life Expectancy in Japan: Evidence From a Longitudinal Study.

Background and Objectives: Existing research has suggested that older adults in Japan enjoy phenomenal physical health status, but they have poor subjective well-being (SWB). Limited empirical evidence exists, however, on how physical health and SWB intersect and are linked to the lives of older men and women in Japan. Using the concept of health expectancy, this study examines the role of SWB, as measured by life satisfaction, in the mortality and morbidity experiences of Japanese adults aged 65 years and older. Research Design and Methods: We used the nationally representative Nihon University Japanese Longitudinal Study of Aging, 1999-2009. Our measurement of morbidity is disability, based on difficulty in activities in daily living (ADLs) and instrumental ADLs. We use the Interpolation of Markov Chains approach to compute life expectancy (LE), LE without disability (active LE), and LE with differing severity of disability for those who are satisfied with life and for those who are not. Results: We documented significant differences in LE and active LE by the state of life satisfaction among older adults in Japan. Men and women who are satisfied with life are expected to live longer and spend more years without having disability compared to those who are not satisfied. We found no differences in the length of life with disability of differing severity by the state of life satisfaction. Discussion and Implications: Our results highlight the important role of SWB at older ages in Japan, because it is directly related to the physical health of its aging population. Fully understanding the health of the older population requires research that focuses on both objective and subjective dimensions of well-being.