Redefining antidepressant efficacy toward long-term recovery

Most studies of antidepressant therapy assess short-term or acute phase eff icacy and tolerability. However, 30% to 50% of patients with major depressi on will experience a relapse during the 4 to 6 months following treatment o f a depressive episode. Patients who do not remit fully during the acute ph ase of therapy are at particularly high risk for relapse. Tn addition, 75% to 80% of patients will experience recurrent depression during their Lifeti me. Thus, full remission and long-term recovery, rather than short-term res ponse, are the desired outcomes from antidepressant treatment. There is a n eed for prospective, long-term studies to investigate the response and reco very to antidepressant therapy. Research conducted by our group at the Univ ersity of Pittsburgh has demonstrated that the rate of recurrence can be si gnificantly reduced across 3 to 5 years of continuous treatment with imipra mine. Although relatively little research on longer term, preventative phar macotherapy has been conducted, studies with newer agents including selecti ve serotonin reuptake inhibitors (SSRIs), nefazodone, and mirtazapine also indicate a lower relapse rate with active drug compared with placebo. The l ong-term efficacy of venlafaxine has been demonstrated in both an extension study and a recent prospective, double-blind discontinuation study. There is increasing evidence that antidepressants, including the serotonin-norepi nephrine reuptake inhibitor (SNRI) venlafaxine, are well tolerated and effe ctive options for longer term therapy.