Early childhood family instability and immune system dysregulation in adolescence.

Exposure to stress is one way in which social disadvantages during childhood may alter biological and psychological systems with long-term consequences. Family social and economic conditions are critical for early childhood development and exposure to difficult family conditions may have lasting physiological effects. However, there is little research linking early childhood conditions with physiological indicators of stress and system dysregulation in adolescence. In this study, we assess how family social and economic instability that occurred in early childhood (birth to age 5) is associated with immune system dysregulation in adolescence, as indicated by DNA shedding of the Epstein-Barr virus (EBV). We utilize a biomarker of EBV obtained through saliva, a non-invasive method of collecting immune-system biomarkers, in 674 adolescents 11-17 years old. Multivariable regression results indicated that experiences of moving into a new parent/caregiver household or moving in with a grandparent during early childhood was associated with an estimated 100% increase in EBV DNA shedding among prior EBV-infected adolescents. Other measures of early childhood family instability, total number of family structure changes and economic insecurity, were marginally significant. Contemporaneous family conditions were not associated with adolescents' EBV DNA shedding.