Abstract 18589: Disparities in Low Cognitive Function Score and Mortality Risk Among Older Adults in the United States

Abstract

Introduction: Low cognitive function predicts mortality in older adults. This study examined cognitive assessment disparities by age, sex, and race, and the association of low cognitive function with mortality. Methods: We analyzed data from the National Health and Nutrition Examination Survey (2011-2014) with linked mortality. Cognitive function was measured by the Digit Symbol Substitution Test (DSST), Consortium to Establish a Registry for Alzheimer's disease Word Test (CERAD), and Animal Fluency Test (AFT). Low cognitive function was defined as scoring below the 25th percentile. Cox regression models was used to assess the association with mortality. Results: The study included 3014 adults aged 60 or older (mean age: 69.7 years; 54.9% women; 9.2% Black, and 78.8% White). A total of 1192 participants had low cognitive function. Older age (70+), female sex, and Black race were associated with lower DSST scores by 11.7 (13.1-10.4) points, 3.4 (2.2-4.6) points, 14.7 (17.2- 12.1) points, respectively, compared with younger age (60-70), male, and White individuals. Low cognitive function was significantly associated with all-cause mortality (HR= 2.04, 95% CI: 1.47-2.81) and cardiovascular mortality (HR= 1.88, 95% CI: 1.41-2.50) after adjusting for age, sex, race/ethnicity, education, income, employment status, physical activity, and smoking. These associations were consistent across all measures of cognitive function. There were no significant interactions in HRs for mortality by age, sex, and race. Conclusions: In a community-based sample, cognitive dysfunction can double the risk of mortality. Whether this represents a marker or a mediator remains to be determined.