Patients With Congestive Heart Failure Show Greater Incidence Of Cognitive Impairment And Dementia

Abstract

<h3>Background</h3> Cardiac disease, including heart failure (HF) and coronary artery disease (CAD), has been associated with cognitive decline. However, whether there are differences in the association of HF and CAD for incidence of mild cognitive impairment (MCI) or dementia, compared with a reference group, has not been extensively studied. We sought to determine whether HF, CAD, and/or exercise capacity (EC) predicts incidence of MCI or dementia. <h3>Methods</h3> The Mayo Clinic Study of Aging (MCSA), a prospective, population-based cohort study, was probed for this study. At baseline and every 15-months thereafter, subjects were evaluated for MCI and dementia using a standardized protocol involving neuropsychological testing and neurological evaluation. We grouped participants by (1) presence of HF, (2) absence of HF but presence of CAD, and (3) absence of both HF and CAD. Peak workload during maximal exercise test was used to determine EC using metabolic equivalent (MET) equations. Exercise testing data was obtained from clinical records, using the test closest to MCSA enrollment. To evaluate association with incident MCI or dementia, cox proportional hazard models were used adjusted for age, sex, and other clinical predictors of cognitive decline. Participants with MCI at baseline were excluded for MCI analysis and included as an adjustment variable for dementia analysis. <h3>Results</h3> We included 5812 MCSA participants (female: 50%; age: 70±13). Of those, 819 (14%) had HF, 1246 (21%) had CAD without HF, and 3747 participants were without HF or CAD. There were 688 (12%) participants with MCI at baseline. Mean follow-up was 3.9±3.7yrs, with 705 incident cases of MCI (14%) and 272 cases of dementia (5%). The HF group, CAD group, and EC were significant predictors of MCI and dementia (see <b>Table and Figure</b>), however, after adjustments, only HF predicted MCI (Hazard ratio: 1.57; 95% CI: 1.25-1.97; p<0.001) and dementia (Hazard ratio: 1.54; 95% CI: 1.09-2.19; p<0.05) (see <b>Table</b>). <h3>Conclusion</h3> After adjustment for age and known predictors of cognitive decline, participants with HF showed greater incidence of MCI and dementia than participants with and without CAD. Conversely, multivariate adjustment attenuated the effect of CAD without HF and baseline EC on incidence of MCI and dementia.