Association of Cognitive Function with Mortality and Cardiovascular Risk

Abstract Background Cognitive impairment is associated with mortality. However, evidence using population‐based studies is scarce, is limited to one cognitive assessment, and lacks the inclusion of non‐fatal adverse health outcomes. Therefore, we aimed this study to (i) investigate the association of cognitive function with mortality and cardiovascular risk and (ii) determine whether cognitive tests improve the risk‐stratification of endpoints beyond conventional risk factors. Methods We analyzed 946 participants aged ≥55y from a population‐based study who underwent cognitive function and were followed for fatal and nonfatal endpoints between 2001‐2016. Conventional risk factors included age, sex, education, body mass index, smoking, alcohol, antihypertensive treatment, office systolic and diastolic blood pressure, serum total cholesterol, diabetes mellitus, and previous history of cardiovascular diseases. Cognitive function examination included the mini‐mental state examination (MMSE) and selective reminder tests ([SRT], total retrieval, long‐term retrieval, and delayed recall). Our primary endpoint was total mortality and major adverse cardiovascular endpoints (MACE). Statistics included Cox proportional models and the generalized R 2 statistic to test model fit. Results The mean age was 66.3±7.5 years old and 640 (67.6%) were women. During a median follow‐up of 8.5 years, 267 participants died and 187 experienced MACE. The incidence of mortality and MACE per quartiles of MMSE and SRT ranged from 13.1 (95% confidence interval [CI], 8.7‐18.9) to 23.8 (95% CI, 18.3‐30.4) among participants with the highest quartile and from 28.8 (95% CI, 14.9‐47.7) to 43.8 (26.3‐66.2) among participants with the lowest quartile. A lower MMSE score was associated with a higher risk of mortality (hazard ratios [HR] per each ‐4.3 lower MMSE, 1.23; 95% CI, 1.02‐1.48) and MACE (HR, 1.27; 95% CI, 1.09‐1.47). A lower SRT‐delayed recall score was associated with 1.19 (95% CI, 1.04‐1.37) and 1.24 (95% CI, 1.04‐1.46) higher folds of mortality and MACE endpoints. On top of conventional risk factors, the inclusions of MMSE and SRT improved the model performance ( R 2 ranged from 0.51% to 1.65%; P ≤0.028). Conclusions In this population‐based study, cognitive impairment is associated with mortality and CV risk. Given the aging global population, the assessment of cognitive function might help reduce the risk of major preventable health outcomes.