The association of cumulative frailty with subsequent cognitive decline, dementia incidence, and all-cause mortality: a longitudinal cohort study.

BACKGROUND

Frailty is dynamic, but associations of cumulative frailty with later cognition, dementia, and death remain unclear.

METHODS

We analysed Waves 4-8 of the Survey of Health, Ageing and Retirement in Europe. Cumulative frailty was the area under the curve of five-component frailty scores across Waves 4-6. Cognitive change (Waves 7-8), incident dementia, and all-cause mortality were examined using adjusted linear mixed-effects and Cox models.

RESULTS

Cognitive, dementia, and mortality analyses included 11,846, 12,108, and 22,696 participants, respectively. Per 1-SD higher cumulative frailty, annual declines were faster in immediate memory (β = -0.009 SD/year; 95% CI -0.013 to -0.004), delayed memory (-0.005; -0.009 to -0.001), and global cognition (-0.007; -0.010 to -0.003). Versus robust participants, frail participants had higher risks of dementia (HR 5.307; 95% CI 3.504-8.036) and mortality (HR 2.922; 2.437-3.504); dementia associations persisted in competing-risk analysis. Nonlinear associations were observed for global cognition, dementia, and mortality.

CONCLUSION

Greater cumulative frailty was associated with faster cognitive decline and higher dementia and mortality risks, supporting repeated frailty assessment to identify vulnerable older adults.