Retrospective analysis of serum valproate levels and need for an antidepressant drug

The number of past manic episodes is the best predictor of antidepressant-emergent manic switch in a cohort of bipolar depressed patients

The present study sought to identify factors associated with the onset of a manic or hypomanic episode during the month following a new antidepressant therapy in depressed bipolar patients. Patients receiving mood stabilizers for ≥3 months were screened from 400 French centers and were assessed for a 4-week period following prescription of a first or a new antidepressant. Of the 1242 included participants, 4.8% (n=60) experienced antidepressant-emergent manic switch (AEMS). AEMS was more frequently associated with lifetime manic, depressive, and total mood episodes, and with past AEMS. A higher score at two items of the Montgomery-Åsberg Depression Rating Scale (pessimistic and suicidal thoughts) were significantly associated with AEMS. Logistic regression analysis showed that the number of lifetime manic episodes and past AEMS were the two most factors associated with an AEMS. Having more than four past manic episodes was associated with a 2.84 fold increased risk of AEMS. Cumulative number of past mood episodes seems to be the most important factor for switching to a manic episode following antidepressants in patients with bipolar disorder. Longer-term studies are required to further delineate antidepressant causality from natural disease course.

Antidepressant-induced mania: an overview of current controversies

OBJECTIVE

The prevalence, characteristics, and possible risk factors associated with antidepressant-induced mania remain poorly described. The present review sought to identify published rates of antidepressant-induced mania and describe risk factors for its emergence.

METHODS

A MedLine search was conducted of journals that focused on mania or hypomania associated with recent antidepressant use. Data from published reports were augmented with relevant findings from recent clinical trials presented at scientific conferences.

RESULTS

Antidepressant-induced manias have been reported with all major antidepressant classes in a subgroup of about 20-40% of bipolar patients. Lithium may confer better protection against this outcome when compared with other standard mood stabilizers, although switch rates have been reported with comparable frequencies on or off mood stabilizers. Evidence across studies most consistently supports an elevated risk in patients with (i) previous antidepressant-induced manias, (ii) a bipolar family history, and (iii) exposure to multiple antidepressant trials.

CONCLUSION

About one-quarter to one-third of bipolar patients may be inherently susceptible to antidepressant-induced manias. Bipolar patients with a strong genetic loading for bipolar illness whose initial illness begins in adolescence or young adulthood may be especially at risk. Further efforts are needed to better identify high-vulnerability subgroups and differentiate illness-specific from medication-specific factors in mood destabilization.

Avoiding drug-induced switching in patients with bipolar depression

Antidepressant-induced switching is a major risk during the treatment of bipolar depression. Despite several clinical studies, questions remain regarding both the definition of these mood switches and the most appropriate therapeutic strategy to avoid this adverse effect. This review will first briefly consider the current guidelines for the acute treatment of bipolar depression. We will then review the mechanisms of action of antidepressant and mood stabilisers, and the switches induced by various types of antidepressant treatments, or triggered by antidepressant withdrawal, as well as by atypical antipsychotics. We then will address the risk of mood switch according to the type of mood stabiliser used. The propensity to mood switches in bipolar patients is subject to individual differences. Therefore we will describe both the clinical and biological characteristics of patients prone to mood switches under antidepressant treatment. However, the clinical characteristics of the depressive syndrome may also be a key determinant for mood switches. Various data help identify the most appropriate drug management strategies for avoiding mood switches during the treatment of bipolar depression. Selective serotonin reuptake inhibitors appear to be the drugs of first-choice because of the low associated risk of mood switching. Antidepressants must be associated with a mood stabiliser and the most effective in the prevention of switches seems to be lithium. Whatever the mood stabiliser used, effective plasma levels must be ensured. The optimal duration of antidepressant treatment for bipolar depression is still an open issue - prolonged treatments after recovery may be unnecessary and may facilitate mood elation. Moreover, some mood episodes with mixed symptoms can be worsened by antidepressants pointing to the need for a better delineation of the categories of symptoms requiring antidepressant treatment. Finally, as a result of this review, we suggest some propositions to define drug-induced switches in bipolar patients, and to try to delineate which strategies should be recommended in clinical practice to reduce as far as possible the risk of mood switch during the treatment of bipolar depression.