Non-persistence with antidepressants results in poor benefit-risk trade-off. Although antidepressant use in youth is has increased markedly, few utilization studies have been conducted in this population. The objectives were to determine non-persistence with antidepressant treatment in the Quebec youth and identify factors associated with non-persistence.

A retrospective cohort study was conducted using the Quebec health databases (RAMQ). All children (2-14 year-old) and adolescents (15-19 year-old) who were new users of antidepressants between 1997 and 2005 were followed for up to 12 months after treatment initiation. Non-persistence was defined as treatment duration with any antidepressant of less than 6 months. Independent variables included i) treatment characteristics; ii) patient characteristics.

53% of children and 29% of adolescents who were dispensed antidepressants were males. Only 60% of children and 75% of adolescents had received a psychiatric diagnosis that may require antidepressants. SSRIs were less prescribed in children than in adolescents (33% vs. 59%) unlike tricyclics (51 % vs 20%). General practitioners were the main prescribers in adolescents but not in children. Overall, 58% of patients were non-persistent. Non-persistence was associated with low maintenance dosages, absence of medical follow-up and being prescribed tricyclics as opposed to SSRIs. [respectively, OR 1.2 (95%CI 1.1-1.3), OR 1.6 (95%CI 1.4-1.7), and OR 2.3 (95%CI 2-2.4)].

Children and adolescents appear to be two distinct sub-populations with respect to antidepressant use; adolescents being very similar to adults. However, factors associated with non-persistence are similar for both age groups.