What do trajectories of childhood socioeconomic status tell us about markers of cardiovascular health in adolescence?

OBJECTIVE The current study examined trajectories of socioeconomic status (SES) throughout childhood and their relationship to markers of cardiovascular health in adolescence. The goal was to determine whether early-life SES, current SES, cumulative SES, and/or social mobility best explained the relationship between SES experiences across an adolescent's life span and current blood pressure (BP), heart rate (HR), and body mass index (BMI). DESIGN One hundred two adolescents completed cardiovascular health assessments including systolic blood pressure, diastolic blood pressure, HR, and BMI. Parents reported on family SES, indicating the number of bedrooms in the family home for each year of the child's life. RESULTS Using Jones, Nagin, and Roeder's semiparametric group-based method, four distinct trajectories of childhood SES were identified. Trajectory groups were differentially related to adolescents' systolic blood pressure and diastolic blood pressure. A trajectory showing low early-life SES that increased through childhood was associated with the highest BP in adolescence. Partial correlation analyses specifically examining the various life-course scenarios similarly indicated that early-life SES was the strongest predictor of adolescents' BP. Trajectories of childhood SES were unrelated to HR and BMI. CONCLUSIONS Of the life-course models that we tested, an early-life SES model best explained adolescents' current BP. These findings point toward early-life developmental processes as potential candidates for explaining the relationship between SES and risk factors related to cardiovascular disease. They suggest that interventions designed to reduce SES health disparities should take place early in a child's life.