Quality of Life and Disability-free Survival in the Elderly: The Locomotive Syndrome and Health Outcome in Aizu Cohort Study.

The Short Form 12 Survey (SF-12) three-component model is used to compute health-related quality of life (QoL): it includes physical, mental, and role-social QoL. We asked whether the SF-12 three-component model is associated with disability-free survival. People ≥65 years old were included ( = 2634). SF-12 scores were assessed at baseline. The outcome was a composite of loss of independence (LoI) and death. LoI was defined using Japan's long-term care insurance categories. Hazard ratios (HRs) for LoI or death were estimated using Cox proportional hazards models. Better physical QoL was inversely associated with LoI or death (adjusted HR per 10-point increase: .88 [95% CI: .81-.96]), but mental QoL was not. Better role-social QoL was inversely associated with LoI or death only among participants with higher than average physical QoL (adjusted HR per 10-point increase: .79 [95% CI: .65-.96], for interaction = .04). Physical QoL was associated with disability-free survival, and role-social QoL was associated with disability-free survival among those with better physical QoL.