Aging Issues in Japan and Taiwan
A Cross-national Comparison between Japan and Taiwan on Age Trajectories of Life Satisfaction and Depressive Symptoms from Midlife to Older Adulthood
Paper Presentation in a Themed Session Yun An Chen
The growth in the number of older persons within Taiwan and Japan creates considerable challenges relating to the aging experiences across countries. Although older age is easily complicated by comorbidities, older adults in different cultures are exposed to different social and medical environments and are shaped with variant resilience. The aging experiences between Taiwanese and Japanese in terms of life satisfaction and depressive symptoms are not known. This study analyzes participants enrolled in the 1996 Taiwan Longitudinal Study on Aging (TLSA, N=5,131), the National Survey of the Japanese Elderly (NSJE, N=2,429), and their follow-up data every three to four years till 2007. Results show that Japanese seniors initially show a melancholy (Taiwan: 4.288, Japan: 8.112) relative to the elderly in Taiwan, but their satisfaction with life is similar (Taiwan: 2.127, Japan: 2.207). However, changes in the elderly in Taiwan did not significantly improve melancholic scores, while it slightly increased for older Japanese. Life satisfaction increased during aging in Taiwanese elderly but decreased in Japanese elderly. The effect of generations also affects the psychological well-being of the elderly in Taiwan and Japan. In terms of depressive symptoms, the elderly in Taiwan over seventy-six years on average increased by about three points and the elderly in Japan increased by about one point. Depressive symptoms of the elderly in Taiwan is mainly influenced by generation rather than aging, while the Japanese melancholy is affected by age and generation.
Cognitive Ageing in Taiwan and Japan: The Age and Cohort Effect
Paper Presentation in a Themed Session Hsiang Min Huang
Taiwan is one of the fastest aging countries, and Japan has the highest proportion of older adults in the world. Although longitudinal patterns of change for cognitive function are well-documented in the literature, only a scarce amount of research examines those patterns with age trajectories and conduct cross-national comparison. Additionally, existing studies are limited by their modeling approach, which generally delineates long-term change by time (year) but not by age. Complicated by the heterogeneous age constitutions of the older populations at baseline and over time, the existing approach generally cannot clarify if changes in the long-term observations overtime were due to age or cohort effect. This study using two comparable nationally representative datasets in Taiwan and Japan with participants from the Taiwan Longitudinal Study on Aging (TLSA) and the National Survey of the Japanese Elderly (NSJE). Hierarchical linear model was used to clarify the longitudinal changes in cognitive function. Age and cohort model tested the cognitive impairment trajectories for older adults assessed with Short Portable Mental State Questionnaire (SPMSQ). Results show that the Japanese elderly seem to have better cognitive function than Taiwanese elderly during aging, and the elderly in Taiwan have significantly decreased cognitive function scores with age, whereas Japan does not. The effects of cohorts also affect the cognitive function of the elderly in Taiwan and Japan. For example, among the elderly people after the age of eighty-five, Taiwan dropped an average of about four points on average while Japan only dropped about 2.5 points.
Are Age Trajectories of Physical Function from Midlife to Older Adulthood Similar between Japan and Taiwan?
Paper Presentation in a Themed Session Ching Ju Chiu
Physical function is one of the most critical predictors for quality of life during older adulthood. Gaps in research documenting age trajectory of functional health not only limit our ability to access aging quality across countries but also diminish the practicality of culturally adapted aging policies. This study delineates age trajectories of limitations in physical function, including activities of daily living (ADLs), intellectual activities of daily living (IADLs), mobility, and frailty from midlife to older age. The study analyzes two nationally representative older adults' surveys in Taiwan and in Japan, the Taiwan Longitudinal Study on Aging, TLSA 1996-2007 and the National Survey of the Japanese Elderly, NSJE 1996-2006, and employs multilevel modeling and cohort sequential design. Results show that Taiwanese elderly reported significantly higher limitations in ADLs and frailty than Japanese elderly at the same age. In addition, significant increases in limitations in ADLs and IADLs were observed at a younger age in Taiwan than in Japan, starting from sixty-six in Taiwan but from seventy-one in Japan. Furthermore, limitations in both IADLs and mobility increased significantly with greater age in Taiwan than in Japan. There were 1.46 (p<.05) and 1.85 (p<.001) fold, respectively. The gap between the disability of Taiwanese and Japanese elderly was more obvious in older generations/cohorts. Taking the eighty-five-year-old generation as an example, Taiwanese elderly reported 6.687 limitations in ADLs, while Japan only reported 2.046, and similarly, 9.290 v.s. 3.834 in IADLs, 14.652 v.s. 5.600 in mobility, and 1.873 v.s.1.601 in frailty.
