Loneliness Predicts Progression of Frailty in Married and Widowed, but Not Unmarried Community Dwelling Older Adults

BACKGROUND: Loneliness is highly prevalent among older adults and is associated with frailty. Most studies consider loneliness in isolation without consideration for structural and functional measures of social relationships - and longitudinal studies are scarce. OBJECTIVES: This study examined longitudinal associations between loneliness and frailty and analyzed how structural and functional social measures influence these associations. DESIGN: Linear mixed effects models examined longitudinal associations between loneliness and frailty assessed with the frailty index (scale 0-100). Models were adjusted for baseline age, gender, education, depressive symptoms, global cognition, and structural (e.g., social network, marital status), and functional social measures (e.g., social, cognitive, and physical activity, and social support). PARTICIPANTS: Loneliness and frailty data from 1,931 older adults without dementia at baseline from the Rush Memory and Aging Project were examined (mean age 79.6 ± 7.7 years, 74.9% female). MEASUREMENTS: Baseline loneliness assessed by the de Jong Gierveld Loneliness Scale was the predictor of interest. RESULTS: Frailty increased significantly over a mean follow-up period of 4.6 years. Effects of loneliness on frailty were modified by marital status. Loneliness predicted an additional accumulation of 0.37 and 0.34 deficits on the frailty index per year in married and widowed individuals respectively, compared to those who were not lonely (married: p=0.009, CI 0.09, 0.64; widowed: p=0.005, CI 0.1, 0.58). Loneliness did not predict frailty progression in unmarried individuals. CONCLUSIONS: Loneliness predicts frailty progression, highlighting the importance of social determinants on physical health in aging.