[A prospective dual-cohort study on the association between frailty index outcomes and cardiovascular disease onset risk in elderly diabetic populations].

This study evaluated the association between frailty index (FI) transitions and the risk of incident cardiovascular disease (CVD) in older adults with diabetes. A total of 891 and 827 diabetic participants were enrolled from the China Health and Retirement Longitudinal Study (CHARLS) and the English Longitudinal Study of Ageing (ELSA), with 439 and 344 incident CVD cases documented during follow-up, respectively. Participants were classified into seven FI transition patterns. Cox proportional hazards models were used to assess the relationship between FI transitions and CVD incidence, while Fine-Gray subdistribution hazard models were applied to account for competing risks. Fixed-effects models were employed to meta-analyze the results from both cohorts and calculate pooled hazard ratios (HR) with 95% confidence intervals (CI). The two-cohort meta-analysis revealed that, compared with the "robust➝robust" group, the "pre-frail➝frail" group (HR=2.04, 95%CI: 1.66-2.51), the "frail➝frail" group (HR=2.03, 95%CI: 1.63-2.53), and the "robust➝pre-frail/frail" group (HR=1.60, 95%CI: 1.32-1.94) had significantly higher risks of incident CVD (all P<0.001). In the Fine-Gray competing-risk models treating non-CVD death as the competing event, the pooled meta-analysis yielded corresponding subdistribution HR (sHR) of 1.90 (95%CI: 1.55-2.33), 1.87 (95%CI: 1.50-2.31), and 1.50 (95%CI: 1.23-1.83) for the same three groups, respectively. In conclusion, deterioration to or persistence of frailty is associated with an elevated risk of CVD in older adults with diabetes, and these associations remained robust after competing-risk validation.