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

To examine the incidence of suicidal and violent behaviour following initiation of antidepressant medication.

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.

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.

Higher rates of suicidal behaviour in the weeks following initiation of antidepressant medication probably reflect disease severity and a delay in mood response.