Abstract 172: Vascular Predictors Of Cognitive Impairment In Patients With And Without Cardiovascular Disease: Results From Nhanes 1998-2001.

Abstract

Objective: To assess predictors of cognitive dysfunction in a nationwide sample of adults 60 years or older with and without cardiovascular disease (CVD) Methods: In non-institutionalized US adults randomly selected to participate in the National Health and Nutrition Examination Survey (NHANES), we used the survey-collected digit symbol substitution test (DSST) score as a surrogate of cognitive function. Stratified analysis was performed to sort out the effects of CVD and vascular risk factors on the DSST score. Univariate logistic regression was used to identify significant associations that were used to create an adjusted multivariate analysis. Results: The studied sample included 1607 participants, mean age 70.1 ± 0.3 years, 43% men, 85% Non-Hispanic Whites, 7% Hispanic and 5% non-Hispanic Black. Vascular risk factors included hypertension (HTN) in 68%, Diabetes (DM) in 16%, Dyslipidemia in 75%, and current smoking in 12%. Cardiovascular disease was reported in 20.8% -- 3.2 % stroke, 16.5 % cardiac disease and 1.1% both. In univariate analysis, statistically significant predictors of a lower DSS score were age (β -0.92 per year), Hispanic and Non-Hispanic Black ethnicities compared to non-Hispanic whites (β -18.1 and β -15.0, respectively), HTN (β -6.1), DM (β -7.6) and CVD (β -7.5); greater education and income both predicted higher DSS scores (β 9.7 and 5.3, respectively). Multivariate analysis confirmed all associations with the exception of HTN (β -1.4, P=0.08). In this adjusted model, both stroke and cardiac disease were independent predictors of lower DSS score (β -5.3 and -2.2, respectively). Stratifying by CVD status using the same multivariate model, DM was the only modifiable vascular risk factor predicting lower DSS score in those without CVD (β -4.8, P=0.001), whereas HTN was associated with lower DSST score only in those who reported having CVD (β -4.6, P=0.05). Conclusion: We confirmed the deleterious effects of HTN and DM on cognition in this nationwide sample, but showed that DM was associated with worse cognition in those without reported CVD, while HTN had a significant negative impact on cognition only in those who already had CVD. The mechanisms underlying these differential associations need further study.