Associations of changes in frailty with multiple chronic diseases in middle aged and elderly adults

Although the impact of baseline frailty status on chronic disease risks has been well-established, evidence on the associations between changes in frailty status and the incidence of new-onset chronic diseases remains limited.

A retrospective study of prospectively collected data from the China Health and Retirement Longitudinal Study (CHARLS) including 7 021 adults aged 45 years or older. Frailty status was evaluated by the Rockwood frailty index and classified as robust, pre-frail, or frail. Changes in frailty status were assessed by frailty status at baseline (2011) and the second survey (2013). All chronic diseases were identified by self-reported physician diagnosis. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% CIs.

Compared to stable robust participants, robust participants who progressed to pre-frail/frail status had significantly elevated risks of all chronic diseases studied (HRs: 1.38-2.73), except for cancer (HR: 1.32; 95% CI: 0.83-2.12). Pre-frail participants who progressed to frail status showed only significantly elevated risks of hypertension (HR: 1.34; 95% CI: 1.01-1.77) and memory disease (HR: 1.63; 95% CI: 1.11-2.39) compared to stable pre-frail participants. In contrast, pre-frail participants who recovered to robust status demonstrated decreased risks of CVD, heart disease, stroke, kidney disease, digestive disease, psychiatric disease, and memory disease than stable pre-frail participants (HRs: 0.39-0.66). Similarly, frail participants who recovered to robust/pre-frail status also showed decreased risks of CVD, stroke, diabetes, psychiatric disease, and memory disease compared to stable frail participants (HRs: 0.39-0.73).

Different changes in frailty status are associated with different risks of new-onset chronic diseases. Progression of frailty status increases risks of almost all chronic diseases, while recovery of frailty status decreases risks of approximately half of all chronic diseases.