Perceived Social Support and Inflammatory Markers over the Life Course: Evaluating the Buffering vs. Direct Effects Hypotheses of Social Support Using the Multi-Ethnic Study of Atherosclerosis

Briana Mezuk, University of Michigan
Ana Diez Roux, University of Michigan
Teresa E. Seeman, University of California, Los Angeles
Mary Cushman, University of Vermont

The health benefits associated with social support may be due to its buffering effects on stress. In the Multi-Ethnic Study of Atherosclerosis, we used ANOVA and linear regression to assess the independent and interacting associations of perceived social support (PSS) and chronic stress on systemic inflammation as indicated by interleukin-6 (IL-6) and assessed whether these differed by gender and age-cohort. ANOVA indicated a main association of stress (P<0.017) but not PSS (P=0.661) with IL-6, and their interaction between not significant. Stratified analyses indicated the interaction between PSS and stress was only significant among the oldest cohort (aged 75-84) of men, such that greater stress was associated with higher IL-6 among those with low PSS (mean difference in IL-6 per SD of stress: 0.15pg/ml) but was not associated with IL-6 in those with high PSS (P for interaction: 0.039). PSS has little association, either through direct or stress-buffering pathways, on inflammation.