Quality of Life among Community-Dwelling Middle-Aged and Older Adults: Function Matters More than Multimorbidity

Objectives: Quality of life stands for the comprehensive assessment for health conditions and the central concerns in the seniors' care. The inter-relationship between health-related quality of life (HRQoL) and multimorbidity among community-dwelling healthy older adults remains uncertain. Methods: Data of 1839 participants from the I-Lan Longitudinal Aging Study were excerpted for analysis. Functional status and HRQoL were measured by the Functional Autonomy Measurement System and the Chinese version of 12-item Short-Form Health Survey version 2. Poor HRQoL was defined as lowest quintile of physical and mental components summaries (PCS and MCS). Multivariable linear and logistic regression analysis were applied to explore associations between variables of interest. Results: Adjusted for potential confounders, multivariable linear regression showed that multimorbidity and functional impairment were negatively associated with PCS (13 coefficients -1.8 vs. -8.4) and MCS (13 coefficients -1.9 vs. -4.8). Logistic regression affirmed similar associations that the odds of being poor HRQoL were 1.6 (95% CI 1.1-2.2) for multimorbidity, and 5.4 (95% CI 2.8-10.3) for functional impairment in PCS; 1.9 (95% CI 1.4-2.6) for multimorbidity and 6.0 (95%CI 3.2-11.5) for functional impairment in MCS. Adjusted for depressive symptoms and cognitive performance, functional impairment was significantly associated with poor physical component (OR:4.68, 95% CI: 0.35-19.34, p<0.001) and mental component in HRQoL (OR:2.4, 95% CI: 1.1-5.5, p=0.032), but the associations were insignificant in multimorbidity. Conclusions: Findings from the study strengthened the importance of functional performance on HRQoL among community-living middle-aged and older adults, which is essential in community health promotion activities and health service programs.