Depression and anxiety as mediators of the relationship between sleep disturbance and somatic symptoms among adolescents on a psychiatric inpatient unit.

Background: This study investigated the relationship between sleep disturbance and somatic symptoms among adolescents residing on a psychiatric inpatient unit. Given the evidence that sleep disturbance may precede the onset of depression and anxiety and the clear associations between mood and somatic symptoms, depression and anxiety were considered as potential mediators of this relationship. Gender was tested as a potential moderator of the relationship between sleep disturbance and depression and anxiety, respectively. Method: A convenience sample of 83 adolescents completed a packet of self-report measures after admission to the unit. Measures assessed depression, sleep disturbance, anxiety, and somatic symptoms. Mediation and moderation analyses were conducted using SPSS PROCESS macro. Results: With anxiety included as a covariate, the overall indirect effect of sleep disturbance on somatic symptoms through depression was significant. No significant moderation effects were found, although females reported significantly higher levels of sleep disturbance, depression, anxiety, and somatic symptoms than males. Conclusions: Results indicated that depression mediated the relationship between sleep disturbance and somatic symptoms above and beyond the effects of anxiety. These findings suggest that interventions aimed at reducing the negative effects of sleep disturbance should also target mood in this population. Individual differences including gender should be considered when developing interventions.