Persistent Low Positive Affect and Sleep Disturbance across Adolescence Moderate Link between Stress and Depressive Symptoms in Early Adulthood.

The purpose of this study was to characterize the association between recent major life events and depressive symptoms during early adulthood, and to determine whether adolescents with chronically low positive affect or persistent sleep disturbance were more vulnerable to the link between stress and depressive symptoms. Adolescents (n = 147; 63.9% female; 33.7% non-Hispanic white) were recruited in 10th-11th grade and re-assessed 2 and 4 years later. At each assessment, adolescents completed measures of positive affect and sleep disturbances. At the final assessment, participants reported on their exposure to major life events in the past 12 months. Exposure to more major life events in the past year was associated with greater depressive symptoms in early adulthood. Chronically low positive affect and persistent sleep disturbances throughout adolescence each independently moderated this relationship. Specifically, only participants reporting low positive affect across the three assessments showed a positive and significant association between major life events and depressive symptoms. Further, only participants reporting sleep disturbances at all three assessments showed a positive and significant association between major life events and depressive symptoms. Chronically low positive affect and persistent sleep disturbances during adolescence may be useful indicators of risk for depression during early adulthood. Further, interventions targeting adolescent sleep disturbances and improving positive affect may be useful in reducing the risk for depression following life stress during this high risk developmental phase.