Social integration and risk of mortality among African-Americans: the Jackson heart study

Evidence suggests that greater social integration is related to lower mortality rates. However, studies among African-Americans are limited. We examined whether higher social integration was associated with lower mortality in 5306 African-Americans from the Jackson Heart Study, who completed the Berkman-Syme Social Network Index in 2000-2004 and were followed until 2018.

We estimated hazard ratios (HR) of mortality by categories of the Social Network Index (i.e., high social isolation, moderate social isolation [reference group], moderate social integration, high social integration) using Cox proportional hazard models. Covariates included baseline sociodemographics, depressive symptoms, health conditions, and health behaviors.

Compared with moderate isolation, moderate integration was associated with an 11% lower mortality rate (HR = 0.89, 95% confidence interval [CI] 0.77, 1.03), and high integration was associated with a 25% lower mortality rate (HR = 0.75, 95% CI 0.64, 0.87), controlling for sociodemographics and depressive symptoms; compared with moderate isolation, high isolation was related to a 34% higher mortality rate (HR = 1.34, 95% CI 1.00, 1.79). Further adjustment of potential mediators (health conditions and health behaviors) only slightly attenuated HRs (e.g., HR_{moderate integration} = 0.90, 95% CI 0.78, 1.05; HR_{high integration} = 0.77, 95% CI 0.66, 0.89).

Social integration may be a psychosocial health asset with future work needed to identify biobehavioral processes underlying observed associations with mortality among African-Americans.