Social frailty increases the risk of all-cause mortality: a longitudinal analysis of the English Longitudinal Study of Ageing

Objectives Social frailty is a common condition in older people, but its consequences are largely unknown. Therefore, in this longitudinal analysis, we aimed to investigate the association between social frailty and risk of all-cause mortality in a large sample of older people. Design Longitudinal, cohort. Settings and participants Older people participating to the English Longitudinal Study of Ageing (ELSA). Methods Social frailty was defined based on financial difficulty, household status, social activity, and contacts with other people: social frailty was defined as ≥2 points, social pre-frailty (1 point), and robustness (0 points). Survival status during ten years of follow-up was assessed using administrative data. Cox proportional hazard models were used to estimate adjusted hazard ratios (HR) and 95 % confidence intervals (95 % CI) of the association between social frailty status and all-cause mortality. Results At baseline, compared to social robust participants, social frail subjects reported a significant higher presence of potential risk factors for all-cause mortality. During the ten years of follow-up, after adjusting for 10 potential confounders, social frailty at baseline (vs. robustness) was associated with a significantly higher risk of death (HR = 1.31; 95 % CI: 1.04–1.64; p = 0.02), whilst social pre-frail was not. Among the single factors contributing to social frailty, poverty increased the risk of all-cause mortality by approximately 60 % (HR = 1.60; 95 % CI: 1.33–1.93; p < 0.0001) as well as living alone (HR = 1.46; 95 % CI: 1.10–1.94; p = 0.009). Conclusions and implications Social frailty was significantly associated with all-cause mortality in a large cohort of older people, highlighting the importance of identifying this phenomenon in older adults to inform targeted intervention efforts.