Abstract
BACKGROUND: Researchers have emphasized the importance of examining how different factors affect men's and women's functional status over time. To date, the literature is unclear about whether sex affects the rate of change in disability in middle to older age. Researchers have further emphasized the importance of examining how different factors affect men's and women's functional status over time. We examined (a) sex differences in disability trends and (b) the determinants of the rate of change in disability for men and women 50 years and older. METHODS: This study utilized the Taiwan Longitudinal Study on Aging Survey, a nationally representative database (four waves of survey data 1996-2007, N = 3429). We modeled and compared the differences in disability trends and the influences of determinants on trends among men and women using multiple-indicator and multiple-group latent growth curves modeling (LGCM). Equality constraints were imposed on 10 determinants across groups. RESULTS: Once disability began, women progressed toward greater disability 18% faster than men. Greater age added about 1.2 times the burden to the rate of change in disability for women than men (p < 0.001). More comorbidities also added significantly more burden to baseline disability and rate of change in disability among women than men (p < 0.001), but women benefited more from higher education levels in lower baseline disability and slower rate of change. Having a better social network was associated with lower baseline disability among women only (p < 0.05). For both men and women, physically active leisure-time activities were beneficial in lower baseline disability (p (men and women) < 0.001) and rate of change in disability (p (men) < 0.01; p (women) < 0.05), with no significant differences between groups. CONCLUSIONS: Age may widen the sex gap in the rate of change in disability. However, both sexes benefit from participating in leisure-time activities. Promoting health literacy improves health outcomes and physical function among women.