The association of race, sex, and neighborhood disadvantage with baroreflex sensitivity in the U.S. POINTER Neurovascular ancillary study

Abstract

AbstractBackgroundThe arterial baroreflex maintains stable blood flow to the brain. Reduced baroreflex sensitivity for modulation of heart rate (BRS) has been observed in patients with Alzheimer’s disease (AD) and mild cognitive impairment and may be impacted by race, ethnicity, sex, and socioeconomic factors such as the Area Deprivation Index (ADI), a validated, neighborhood‐level composite index that incorporates 17 social determinants of health. However, these relationships have not been well described.MethodThis study utilized baseline data from 196 participants enrolled in the U.S. POINTER Neurovascular study, an ancillary to the parent U.S. POINTER multi‐site lifestyle intervention trial that adds assessments of autonomic function and vascular structure and function. BRS was calculated from continuous blood pressure and electrocardiogram recording using the slope of the regression line between changes in systolic blood pressure and RR interval values in the same direction, with higher BRS indicating better autonomic function. ADI scores ranging from 1 to 10 were calculated using 9‐digit zip codes, with 10 indicating the greatest disadvantage. Analysis of variance and linear regression were used to evaluate associations between measures of interest.ResultThe average age of the study population was 67.9 ± 5.4 years, 64 (17%) were males, and 60 (30.6%) identified as people of color (POC). Overall, the mean BRS was 9.2 ± 4.6 ms/mmHg, and the average ADI score was 4.56 ± 2.69 (range: 1 to 10), corresponding to a national ADI percentile of 40.7 ± 26.1 (range: 3 to 100). Less than a quarter of participants (n = 42, 21.4%) had an ADI percentile >67, indicating a moderate to high level of neighborhood disadvantage. White participants had lower BRS compared to POC (8.60 ± 4.49 vs. 10.60 ± 4.61 ms/mmHg, p = 0.0048). In a multiple regression model adjusting for demographics and ADI, sex (p = 0.0283), race and ethnicity (p = 0.0049), and education (p = 0.0196) were significantly associated with BRS, indicating better autonomic function in men, POC, and those with higher education. ADI was not associated with BRS.ConclusionRace, ethnicity, and education impact autonomic function. Further investigations are needed to assess the impact of other demographic and socioeconomic factors on neurovascular health.