The Association between Depression Symptoms and Disability Outcomes in Older Adults at Risk for Mobility Decline

Objective To assess the association between depression symptoms and physical functioning and participation in daily life over two years in older adults at risk for mobility decline. Design A secondary analysis of a two-year observational data from the Boston Rehabilitative Impairment Study of the Elderly (Boston RISE). Setting Nine primary care clinics within a single health care system. Participants Participants (N=432; mean age 76.6 ± 7.0, 65-96 years; 67.7% women) were community-dwelling adults (>65 years) at risk of mobility decline. Interventions Not applicable. Main Outcome Measures Secondary data analyses of the Late Life Function and Disability Instrument (LLFDI) (primary outcome), Short Physical Performance Battery (secondary outcome), Patient Health Questionnaire-9 (PHQ-9) (predictor). Measures were administered at baseline, 12, and 24 months. Participants completed a self-report survey asking about 16 medical comorbidities and demographic information was collected at baseline. Results Participants had an average PHQ-9 score of 1.3±3.1, range 0-24 at baseline. 29% of participants reported a history of depression. Greater depression symptoms were associated with lower physical functioning (Unstandardized beta [B] = -0.14, SE = 0.05, p = .011) and restricted participation (frequency subscale: B = -0.21, SE = 0.11, p =.001; limitation subscale: B = -0.45, SE= 0.04, p <.001) cross-sectionally, over two years. PHQ-9 was not significantly associated with the rate of change of LLFDI over two years. Conclusions Treating depression in primary care may be an important strategy for reducing the burden of functional limitations and participation restrictions at any one time. Further research is needed on treatment models to co-target depression and physical functioning among at-risk older adults.