Incidence of suicidal behaviour and violent crime following antidepressant medication: a Danish cohort study.

OBJECTIVE: To examine the incidence of suicidal and violent behaviour following initiation of antidepressant medication. METHOD: Cohorts of 997 911 conscripts and 95 794 patients with a first-time affective disorder were followed for purchase of antidepressant medication, suicide, suicide attempts and conviction for violent crime in Danish registries between 1997 through 2015. Incidence of outcomes was estimated for the first 28 days, 28-365 days or later after initiation of antidepressants or study entry. RESULTS: Of 16.5% of conscripts and 73.7% of patients with affective disorders initiated antidepressant medication. Incidence of suicide was 3-4 times higher during the first 28 days after initiation compared to the rates in the following year in both cohorts. A similar trend was seen among the untreated patients with affective disorders, whereas suicide incidence was stable at a low level among conscripts not treated with antidepressants. Incidence of attempted suicide was highest during the 28 days before and after initiation of antidepressants, while rates of violent crime were similar before and after initiation. These trends in incidence were independent of class of antidepressant. CONCLUSION: Higher rates of suicidal behaviour in the weeks following initiation of antidepressant medication probably reflect disease severity and a delay in mood response.

The association between antidepressant use and assisted reproductive technology (ART) treatment in Danish women: A national registry-based cohort study.

OBJECTIVE: To investigate (1) if antidepressant use among women in assisted reproductive technology (ART) treatment and among women without ART treatment influences cumulative live birth rates (CLBR) and number of initiated treatment cycles per woman, (2) whether women undergoing ART treatment are at higher risk of initiating use of antidepressants compared to women not having undergone ART, (3) if mothers after ART treatment have higher risk for postpartum use of antidepressants after ART treatment compared to mothers not having used ART treatment. STUDY DESIGN: A Danish nation-wide register-based cohort study including all women in ART treatment between 1995 through 2009 and an age-matched comparison group of women not having initiated ART treatment. In both groups, women had no previous children before study entry. The women were followed from time of initiating first ART treatment until time of permanent emigration (> 6 months), date of death, or end of follow-up by 31st of December 2009. Chi-square test was used to assess whether observed differences in CLBR between groups were significant. Adjusted incidence rates (IR) and incidence rate ratio (IRR) with 95 % confidence interval (CI) were calculated using Poisson regression analysis. The main outcome measures were: CLBR, number of initiated ART treatment cycles and IRR of initiating antidepressant use. RESULTS: Women using antidepressants before, during or after ART treatment were significantly older, had a lower CLBR and a lower mean number of initiated ART treatment cycles compared to women in ART treatment with no use of antidepressants. No significant difference was found in the incidence of initiating antidepressant use between women in ART treatment and the comparison group. However, when comparing only women with a live birth, significantly more women in ART treatment initiated antidepressant use in the postpartum period (adjusted incidence rate ratio (IRR) = 2.56 (95 % CI 1.98-3.30; p < 0.001)). CONCLUSION: Generally, women undergoing ART treatment are not at higher risk of initiating use of antidepressants compared with an age-matched comparison group not treated with ART. However, women with antidepressant medication use prior to ART initiate fewer ART treatments and have lower CLBR. Even though it has not been possible to adjust for all relevant confounders and our follow-up period only runs until the end of 2009, we still believe the results of this study to be highly relevant. According to our study, clinicians should be aware that women conceiving after ART treatment might experience an increased level of psychological strain during the postpartum period compared to mothers who conceived without ART.