Long term studies of depression: what is relevant for the physician?

Abstract

Following a meticulous review of long term studies of depression, we conclude that prolonging antidepressant medication after full recovery is clearly beneficial. In this article, we examine recent long term studies that reveal substantial evidence in this sense. However, we advise physicians to keep in mind that this prophylactic effect has been proven for a restricted population, i.e., patients showing recurrent depressive disorders with low comorbidity on axis 1, and having revealed a satisfying response to antidepressant agents during the acute phase of the index episode. This does not mean that antidepressant agents are not useful for patients showing other characteristics, but more studies are needed to assert this possible advantage. We also examine the limited data on chronic forms of depressive disorders. The effect of long term prescription is believed to be advantageous as long as the medication is taken; it has been demonstrated for up to 5 years. Full dosage is indicated even if the effect of active drug over placebo persists at lower doses. The differences between antidepressant agents appear minor and physicians should be more concerned about the long term tolerance of these drugs than their efficacy when choosing the appropriate medication for maintenance treatment. Physicians should also be aware of the greater risk of recurrence during the 6 months following the discontinuation of medication. This risk occurs regardless of the total length of prescription. The possibility that recurrence may be mistaken for withdrawal symptoms cannot be ruled out. Finally, the side-effects of antidepressant drugs are a major concern, particularly when extending the length of prescription. Even though the newer generation medications display a more favorable short-term side-effect profile, the effects of chronic use of these agents are still unclear. Therefore, the decision to extend treatment over several years requires comprehensive discussion with patients and cautious clinical monitoring to identify potential late-onset side effects.