Antidepressant tolerability in anxious and depressed youth at high risk for bipolar disorder: a prospective naturalistic treatment study

Objective Depressive and anxiety disorders are common in youth who are at risk for bipolar disorder (i.e., youth who have at least one parent with bipolar disorder) and antidepressants are commonly prescribed as treatment. However, there are few data regarding the safety and tolerability of antidepressants in this population. Therefore, we sought to prospectively examine the effects of these medications in children and adolescents who are diagnosed with depressive or anxiety disorders and have a parent with bipolar I disorder. Methods Youth aged 9–20 years, with at least one parent with bipolar I disorder [high risk (HR)], were recruited (n = 118) and assessed using semi‐structured diagnostic interviews. Participants were prospectively evaluated using a modified version of the Longitudinal Interval Follow‐up Evaluation to assess changes in affective and anxiety symptoms and were treated naturalistically. Results Over the course of 43–227 weeks (mean duration of follow‐up: 106 ± 55 weeks), 21% (n = 25) of youth had antidepressant exposure and, of these, 57% (n = 12) had an adverse reaction (e.g., irritability, aggression, impulsivity, or hyperactivity) that led to antidepressant discontinuation. Those patients who experienced an adverse reaction were significantly younger than those who did not (p = 0.02) and discontinuation of antidepressant therapy secondary to an adverse event occurred at an average of 16.7 ± 17.4 weeks (median: 11 weeks, range: 2–57 weeks). Cox proportional hazard analyses yielded a hazard ratio of 0.725 (p = 0.03), suggesting that there is a 27% decrease in the likelihood of an antidepressant‐related adverse event leading to discontinuation with each one‐year increase in age. Conclusions Antidepressant medications may be poorly tolerated in youth with a familial risk for developing mania. Controlled studies further assessing treatments for depression and anxiety in HR youth are urgently needed.