Peers' parental education and cardiovascular disease risk in adulthood: The mediating role of health-related behaviors.

Rationale: Although there is a growing body of empirical evidence on the relationship between peers' parental education and adolescents' educational outcomes, little is known about whether exposure to highly educated peers' parents is associated with improved physical health in adulthood.

Objective: This study investigated the relationship between the education level of peers' parents (Wave I) and the risk of developing cardiovascular disease (CVD) in adulthood (Wave IV). Moreover, we considered a set of health-related behaviors (Wave II) as the underlying mechanisms linking peers' parental education to later-life physical health such as substance use (smoking, binge drinking, and marijuana use) and other lifestyle behaviors (physical activity, sedentary behavior, and unhealthy dietary habits).

Methods: Data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), spanning respondents' adolescence to adulthood, were used. To address the endogenous school selection problem and account for the unobserved school-level confounders, this study exploited quasi-experimental within-school/across-cohort variation in peer composition. To formally test for mediation, Sobel tests were conducted.

Results: The results of this study revealed that independent of own parents' education levels, exposure to higher levels of peers' parental education is associated with a lower CVD risk score in adulthood. For a one-standard-deviation increase in peers' parental education-that is, about a 0.98-year increase in grademates' parental educational attainment, a CVD risk in adulthood increased by about 6.2%. Our mediation analyses showed that part of this association is explained by a decrease in substance use (27% for smoking, 10% for binge drinking, and 11% for marijuana use). In contrast, none of the other lifestyle behaviors evaluated significantly mediated the association.

Conclusion: The study's findings suggest that the role of peers' parents should not be overlooked when developing health-promoting interventions for adolescents. Policymakers and practitioners may wish to increase opportunities for students to benefit from health-related social learning from their peers' highly educated parents.