Abstract
BACKGROUND: Cardiovascular disease (CVD) disproportionately affects Black adults. Greater social networks (SNs), or social connectedness, may lower the risk of CVD events. This study determined the association of SNs and incident CVD and tested mediation by depressive symptoms, hypertension control, and diabetes control. METHODS AND RESULTS: We used the Social Network Index at exam 1 (2000-2004) to develop a continuous standardized SN score and binary categories (high versus low) among participants in the Jackson Heart Study (n=4686; mean age, 54.8 years). Surveillance of coronary heart disease, stroke, and heart failure events occurred after exam 1 (2005 for HF) until 2016. Using Cox proportional hazards regression, we estimated the association of SNs and CVD events by sex and tested the mediation of depressive symptoms, hypertension control, and diabetes control. Models adjusted for age, education, health behaviors, CVD comorbidities, and depressive symptoms. Among women, the SN score was associated with a lower hazard of stroke, coronary heart disease, and heart failure after full adjustment (hazard ratio [HR], 0.78 [95% CI, 0.64-0.95]; HR, 0.79 [95% CI, 0.71-0.88]; and HR, 0.78 [95% CI, 0.66-0.92], respectively). SN scores were also associated with a lower hazard of coronary heart disease in men (HR, 0.84 [95% CI, 0.75-0.94]) after full adjustment. High versus low SNs were associated with a lower hazard of coronary heart disease and heart failure among women after full adjustment. There was no evidence of mediation by depressive symptoms, diabetes control, and hypertension control. CONCLUSIONS: Higher SNs may lower the risk of CVD events, especially in women.