The moderating role of sleep hours in the relationship between childhood trauma and depressive symptoms: A longitudinal investigation

Although childhood trauma has been identified as one of the major risk factors for depression, the potential mechanisms behind this relationship remain less clear. As sleep disturbances are associated with both childhood trauma and depression, this study examined the moderating effects of sleep hours on this relationship. The sample consisted of young adults from an international longitudinal survey project (N = 146). Participants completed validated screening measures of childhood trauma and depressive symptoms and reported their sleep hours at baseline (T1), and then reported their depressive symptoms again at follow-up (T2) after 3 months. Multiple regression and moderation analyses were used to analyze the data. T1 childhood trauma was positively correlated to depressive symptoms at both T1 (r = 0.26, p < .01) and T2 (r = 0.21, p < .05). After controlling for demographic variables and T1 depressive symptoms, T1 sleep hours significantly predicted T2 depressive symptoms (β = 0.136, p = .038). Furthermore, the number of sleep hours moderated the effects of T1 childhood trauma on T2 depressive symptoms. T1 childhood trauma predicted T2 depressive symptoms only when sleep hours were low (B = 0.2056, p = .0075). This study provided evidence that childhood trauma was significantly associated with aggravated depressive symptoms under sleep deprivation. Proactive management of sleep problems might be beneficial to people with childhood trauma. Future studies are needed to evaluate sleep-focused interventions for childhood trauma survivors.