Intergenerational transmission of depressive symptoms - The role of gender, socioeconomic circumstances, and the accumulation of parental symptoms

Background: The relationship between parental and offspring depression is well established. Evidence regarding the significance of gender, socioeconomic circumstances, and the accumulation of parental symptoms in intergenerational transmission is, however, mixed and scarce. Methods: Using a 20% random sample of Finns born between 1986 and 1996 (n=138,559), we performed a Cox proportional hazards regression to analyze the incidence of depressive symptoms between ages 15-20 by exposure to maternal and paternal depressive symptoms earlier in life. Depressive symptoms were inferred from antidepressant purchases and/or a diagnosis of depression at outpatient or inpatient health services. Results: Exposure to maternal depressive symptoms posed an equal risk for girls and boys (hazard ratio, HR, 2.09 vs. 2.28 respectively, p =0.077), whereas the effect of paternal depressive symptoms was weaker for girls (HR 1.77 vs. 2.22, p < 0.001). Parental socioeconomic status neither confounded nor moderated these effects. Dual exposure to both maternal and paternal depressive symptoms posed a larger risk than single exposure, and children exposed recurrently at ages 0-5 and 9-14 faced an elevated risk compared with those exposed at only one period. Limitations: Since depressive symptoms were inferred from prescription purchases and treatment records, we were unable to observe untreated depression or to determine the underlying condition the antidepressants were prescribed for. Conclusions: Our results support the idea that maternal depression affects both genders equally, whereas paternal depression affects girls less than boys. We show that parental depression and low socioeconomic status are mainly independent risk factors of adolescent depressive symptoms and do not cause an interactive effect. (C) 2016 Elsevier B.V. All rights reserved.