Abstract
PURPOSE: Physical health-related quality of life (HRQoL) is associated with adverse health outcomes, including hospitalizations and all-cause mortality. However, little is known about how physical HRQoL changes over time in older people and the predictors of this trajectory. This study (a) identified trajectories of physical HRQoL among older people and (b) explored whether economic factors, social health or stressful life events impact physical HRQoL trajectories. METHOD: A cohort of 12,506 relatively 'healthy' community-dwelling Australians aged ≥ 70 years (54.4% females), enrolled in the ASPREE Longitudinal Study of Older Persons (ALSOP) study and was followed for six years. Economic factors, social health and life events in the last 12 months were assessed through a questionnaire at baseline. Physical HRQoL was measured by using the 12-item short form at baseline and annual follow-ups. Growth mixture and structural equation modelling were used to identify physical HRQoL trajectories and their predictors. RESULTS: Four physical HRQoL trajectories were identified-stable low (7.1%), declining (9.0%), stable intermediate (17.9%) and stable high (66.0%). Living in more disadvantaged areas, having a lower household income, no paid work, no voluntary work, loneliness and stressful life events (i.e. spousal illness, friend/family illness, financial problem) were associated with a 10%-152% higher likelihood of being in the stable low or declining physical HRQoL trajectory than the stable high group. CONCLUSION: Specific stressful life events had a greater impact on adverse physical HRQoL trajectories in older people than other factors. Volunteering may prevent physical HRQoL decline and requires further investigation.