Remission in major depression with two antidepressant mechanisms: results from a naturalistic study

Background: Since remission should be the goal of the treatment of depression, the aims of this study were to evaluate the rate of remission obtained with SSRIs in routine clinical practice and to assess alternative treatments with a combined mechanism of action. Methods: The study involved a prospective naturalistic 6-month follow-up of 44 consecutive unipolar depressed (DSM-IV) outpatients. After 6 weeks of treatment with a SSRI, patients were classified as remitted (HAM-D-17 score ≤7), partial responders (≥50% reduction in HAM-D-17 score but still higher than 7) and non-responders. In case of non-response, an antidepressant with noradrenergic action (NaA) was added to the ongoing SSRI treatment or were switched to venlafaxine in monotherapy when NaA was contraindicated. Results: At 6 weeks, eight patients (18.1%) achieved full remission, nine patients (20.5%) were partial responders and 27 (61.4%) non responders. At the end of follow-up 31.8% (n=14) of the initial sample remained remitted with SSRIs, whereas 96.2% (26/27) of previous non-responders experienced remission with the alternative treatment. Non-responders to SSRIs in monotherapy were significantly more likely to show melancholic features and to have higher HAM-D-17 scores and lower GAF scores than remitted patients with SSRIs. Limitations: the observational and naturalistic design of the study determines inherent limitations. Conclusions: this study showed a low remission rate with SSRIs in the long-term treatment of more severe and melancholic depression, and the benefit of using treatments with a combined mechanism of action.