Duration and timing of depression and risk of family dissolution: A register-based cohort study of newly-formed Danish families

Depression is detrimental to partnership stability. However, it remains unclear if and how the duration and timing of depression affect the risk of family dissolution. We conducted a Danish register-based cohort study of newly-formed cohabiting and married couples in 2008 and 2009, who were followed from the second year after family formation. Depressive episodes were defined by individual-level prescription patterns of antidepressant drugs (ATC codes N06A) in either partner. Family dissolution was characterized by the discontinuation of a shared residential address. Using Longitudinal Targeted Minimum Loss-based Estimation, we estimated the risk of family dissolution after 5 years of follow-up under various lengths and timings of depressive episodes. There were 102,335 families included. The covariate-adjusted risk of family dissolution in families without depressive episodes was 30.0 % (95 % CI 29.6–30.4 %) and 35.5 % (95 % CI 29.5–41.5 %) in families with at least one depressive episode during follow-up. The risk of family dissolution increased with the duration of depressive episodes to 42.2 % (95 % CI 40.8–43.6 %) for five coherent years of depression. Depression shortly after family formation carried higher risk of family dissolution; this risk was 42.3 % (95 % CI 38.4–46.3 %) for depression experienced in the first year of family formation versus 32.9 % (95 % CI 31.8–34.0 %) in the fifth year of family formation. Proxy measures of depression by antidepressant prescriptions fails to identify milder depression. Annual measures of family dissolution precluded more fine-grained analyses of time-intervals. Depression is disruptive to family stability, particularly with longer duration and early onset after family formation. •Depression substantially increased the risk of family dissolution.•Enduring depressive episodes was increasingly detrimental to relationship stability.•The dissolution-risk was higher in families where depression presented early after family formation.