[Duration of antidepressant drug treatment and its determinants in France]

Practice guidelines recommend maintaining antidepressant treatment for a long duration (at least six months) after symptomatic improvement. In practice, treatment effectiveness is often jeopardized by non-persistence.

A retrospective cohort study was conducted on a standard sample representative of the members of the French universal health insurance system database, in order to assess antidepressant treatment duration in a real-life setting. 35,053 outpatients who initiated an antidepressant treatment in 2005-2006 were followed up until 2007. Incident antidepressant treatment was defined as no delivery of antidepressant in the six months prior to treatment initiation. Persistence to treatment was defined as antidepressant treatment duration of six months or more. Multivariate analyses were conducted in order to identify characteristics associated with persistence to treatment.

Most antidepressant treatments (n = 28,674; 81.8%) lasted for less than six months and more than half for 28 days at most (n = 20,377; 58.1%). Persistence to treatment was associated with older age (OR 1,13; 95% CI 1.11-1.15), female gender (1.22; 1.15-1.30), chronic disease (1.21; 1.13-1.31), not being on welfare (0.67; 0.60-0.74) and coprescription of anxiolytics (0.36; 0.33-0.38), antipsychotics (0.39; 0.35-0.43) or mood-stabilizers (0.45; 0.39-0.53). Prescribers' specialty was also associated with persistence. Treatments prescribed by general practitioners were less likely to be continued than those prescribed by psychiatrists (1.65; 1.47-1.86).

Non-persistence to antidepressant treatment is very frequent in France. Intervention programs aimed at increasing persistence should target physicians' training and patients' education.