The role of temperament and social support in depressive symptoms: A twin study of mid-aged women

Background: Although research has found that temperament and social support are associated with depression, these relationships have not been explored in conjunction with one another as they relate to depression using a genetically informative design. This study investigated how the association among the three constructs is mediated. Methods: The sample in this study consisted of 326 pairs of adult monozygotic and dizygotic twins drawn from the Swedish Twin Registry. Twins were mothers of adolescent from married or partnered relationships. The genetic and environmental contributions to the association were evaluated by self-reported measures of temperament, social support, and depressive symptoms. Results: Multivariate genetic model fitting revealed that a moderate portion of genetic influences were common among the three central constructs of harm avoidance, perceived social support, and depressive symptoms. Limitations: The results may not be generalizable to depressive disorders in clinical settings. The measures were self-reported from a cross-sectional study. Conclusions: The findings suggest that the heritable component may contribute to genetic influences on an individual's ability to secure social support and thus to genetic risk for depressive symptomatology in women