Remission Rates With 3 Consecutive Antidepressant Trials: Effectiveness for Depressed Outpatients

Objective: This effectiveness study assessed remission rates in patients who had the opportunity to receive up to 3 antidepressant trials if unresponsive.

Method: One hundred seventy-one consecutive outpatients entered 1 of 3 studies for the treatment of major depressive disorder (DSM-IV criteria) from January 1999 through December 2001. This group primarily received fluoxetine as a first treatment in trials lasting 6 to 12 weeks (a small number received gepirone). If unimproved, patients received a second or third trial (primarily clinician’s choice). A standard criterion to determine remission–a score of 7 or less on the 17-item Hamilton Rating Scale for Depression–was used. In order to contrast remission rates with first-generation antidepressants, patients’ outcomes in a previously published study that compared placebo, phenelzine, and imipramine were also examined (N = 420).

Results: In an intent-to-treat analysis, 66% (113/171) of patients who were treated with second-generation antidepressants and 65% (275/420) of patients who were treated with first-generation antidepressants eventually achieved remission.

Conclusions: Remission rates in the effectiveness study are approximately 20% higher than the rates usually cited, a result of our choice to examine outcome following 3 treatment trials. This choice is dictated by good clinical practice. The usual procedure when comparing treatment modalities is to assess outcome after a single antidepressant trial. The cumulative high remission rates suggest antidepressants are effective and should encourage more patients to seek treatment and physicians to develop techniques to improve patient adherence.