Importance: Chronic stress has been posited to contribute to racial disparities in cardiovascular health. Investigation of whether neighborhood- and individual-level stressors mediate this disparity is needed.

Objective: To examine whether racial differences in ideal cardiovascular health (ICH) are attenuated by experiences with neighborhood- and individual-level stressors within a racially and geographically diverse population sample.

Design, setting, and participants: This cross-sectional study examined data from 7720 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study who completed the second in-home visit (2013-2016). The REGARDS study is a population-based, longitudinal study of 30 239 non-Hispanic Black and non-Hispanic White adults aged 45 years or older at baseline (2003-2007). Data for the present study were analyzed from June to July 2021 and in March 2022.

Exposures: Neighborhood physical environment (eg, excessive noise, violence; scored from 7-28, with higher scores indicating more problems), neighborhood safety (scored as very safe, safe, or not safe), neighborhood social cohesion (eg, shared values; scored from 5-25, with higher scores indicating higher cohesion), perceived stress (eg, coping; scored from 0-16, with higher scores indicating greater perceived stress), and the experience of discrimination (yes or no).

Main outcomes and measures: Ideal cardiovascular health (ICH), measured as a composite of 4 health behaviors (cigarette smoking, diet, physical activity, body mass index) and 3 health factors (blood pressure, cholesterol, and glucose levels).

Results: The sample included 7720 participants (mean [SD] age, 71.9 [8.3] years; 4390 women [56.9%]; 2074 Black participants [26.9%]; and 5646 White participants [73.1%]). Black participants compared with White participants reported higher perceived stress (mean [SD] score, 3.2 [2.8] vs 2.8 [2.7]) and more often reported discrimination (77.0% vs 24.0%). Black participants also reported poorer neighborhood physical environment (mean [SD] score, 11.2 [3.8] vs 9.8 [2.9]) and social cohesion (mean [SD] score, 15.5 [2.0] vs 15.7 [1.9]) and more often reported their neighborhoods were unsafe (54.7% vs 24.3%). The odds of having a high total ICH score (ie, closer to ideal) were lower for Black adults compared with White adults, both overall (adjusted odds ratio [AOR], 0.53; 95% CI, 0.45-0.61) and by gender (men: AOR, 0.73 [95% CI, 0.57-0.93]; women: AOR, 0.45 [95% CI, 0.37-0.54]). In mediation analyses, the racial disparity in total ICH score was attenuated by neighborhood physical environment (5.14%), neighborhood safety (6.27%), neighborhood social cohesion (1.41%), and discrimination (11.01%). In stratified analyses, the factors that most attenuated the racial disparity in total ICH scores were neighborhood safety among men (12.32%) and discrimination among women (14.37%). Perceived stress did not attenuate the racial disparity in total ICH scores.

Conclusions and relevance: In this cross-sectional study of Black and White US adults aged 45 years and older, neighborhood-level factors, including safety and physical and social environments, and individual-level factors, including discrimination, attenuated racial disparities in cardiovascular health. Interventional approaches to improve ICH that separately target neighborhood context and discrimination by gender and race are warranted.