Association of Cardiovascular Risk Burden With Risk and Progression of Disability: Mediating Role of Cardiovascular Disease and Cognitive Decline

Background Cardiovascular risk burden has been linked to cardiovascular disease (CVD) and cognitive decline, but its association with disability is unclear. We aimed to examined the association of cardiovascular risk burden assessed by the Framingham general cardiovascular risk score (FGCRS) with the risk and progression of disability and estimated the extent to which CVD and cognitive decline mediate this association. Methods and Results A total of 1480 older adults with no disabilities (mean age=79.32 +/- 7.38 years) from the Rush Memory and Aging Project were followed for up to 21 years. FGCRS at baseline was calculated and categorized into tertiles. Disability was assessed annually with activities of daily living. The number of CVDs was calculated by summing up the CVD events. Global cognitive function was assessed annually with a battery of 19 tests. Data were analyzed using the Cox model, linear mixed effects model, and mediation analysis. At the end of the follow-up, 713 (48.2%) participants developed disability. Compared with the lowest tertile of the FGCRS, the multiadjusted hazards ratios of disability were 1.34 (95% CI, 1.11-1.62) for the highest tertile. In addition, the highest FGCRS was associated with a change in activities of daily living score over time (beta=0.057; 95% CI, 0.021-0.093). The association between FGCRS and change in activities of daily living was 13.8% mediated by the accumulation of CVDs and 25.1% by cognitive decline, respectively. Conclusions Higher cardiovascular risk burden increased the risk of disability and accelerated its progression over time. CVD accumulation and cognitive decline may partially mediate the association.