Association of Heart Rate Variability With Cognitive Performance: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND: Heart rate variability (HRV) is associated with vascular risk factors for dementia, but whether HRV is associated with specific domains of cognitive performance is unclear. METHODS AND RESULTS: In the Multi--Ethnic Study of Atherosclerosis (N=3018; mean age 59.3 +/- 9.2 years), we assessed the relationship of 10--second HRV to scores on tests of global cognitive performance (Cognitive Abilities Screening Instrument), processing speed ( Digit Symbol Coding), and working memory (Digit Span). HRV was computed as the SD of normal--normal intervals (SDNN) and root mean square of successive differences (RMSSD) at Exam 1 (2000-2002) and Exam 5 (2010-2012). Cognitive tests were administered at Exam 5. We report regression coefficients (ss [95% CI]) representing cognitive test score change per 2--fold increase in HRV. After adjustment for age, race/ethnicity, sex, education, apolipoprotein E genotype, and cardiovascular risk factors and incident disease, higher Exam 1 (ss=0.37 [0.06, 0.67]) and Exam 5 (ss=0.31 [0.04, 0.59]) SDNN were associated with better Cognitive Abilities Screening Instrument performance. Higher Exam 1 (ss= 0.80 [0.17, 1.43]) and Exam 5 (ss=0.63 [0.06, 1.20]) SDNN, and Exam 5 RMSSD (ss=0.54 [0.01, 1.08]) were associated with better Digit Symbol Coding performance. Finally, higher Exam 5 SDNN was associated with better Digit Span performance (ss= 0.17 [0.01, 0.33]). Associations were attenuated after adjustment for resting heart rate. CONCLUSIONS: Higher HRV is generally associated with better cognitive performance in this multi--ethnic cohort of aging adults, and further study of the relationship of autonomic function to cognition is warranted.