Antidepressant‐Induced Manic Conversion: A Developmentally Informed Synthesis of the Literature

Chronic exposure to imipramine induces a switch from depression-like to mania-like behavior in female serotonin transporter knockout rats: Role of BDNF signaling in the infralimbic cortex

BACKGROUND

Bipolar disorder (BD) is a highly burdensome psychiatric disorder characterized by alternating states of mania and depression. A major challenge in the clinic is the switch from depression to mania, which is often observed in female BD patients during antidepressant treatment such as imipramine. However, the underlying neural basis is unclear.

METHODS

To investigate the potential neuronal pathways, serotonin transporter knockout (SERT KO) rats, an experimental model of female BD patients, were subjected to a battery of behavioral tests under chronic treatment of the antidepressant imipramine. In addition, the expression of brain-derived neurotrophic factor (BDNF) and its downstream signaling was examined in the prefrontal cortex.

RESULTS

Chronic exposure to imipramine reduced anxiety and sociability and problem-solving capacity, and increased thigmotaxis and day/night activity in all animals, but specifically in female SERT KO rats, compared to female wild-type (WT) rats. Further, we found an activation of BDNF-TrkB-Akt pathway signaling in the infralimbic, but not prelimbic, cortex after chronic imipramine treatment in SERT KO, but not WT, rats.

LIMITATIONS

Repeated testing behaviors could potentially affect the results. Additionally, the imipramine induced changes in behavior and in the BDNF system were measured in separate animals.

CONCLUSIONS

Our study indicates that female SERT KO rats, which mirror the female BD patients with the 5-HTTLPR s-allele, are at higher risk of a switch to mania-like behaviors under imipramine treatment. Activation of the BDNF-TrkB-Akt pathway in the infralimbic cortex might contribute to this phenotype, but causal evidence remains to be provided.

Conversion from depression to bipolar disorder in a cohort of young people in England, 1999-2011: A national record linkage study

OBJECTIVE

To estimate the conversion rate from unipolar depression (ICD10 codes F32-F33) to bipolar disorder (BP) (ICD10 codes F31) in an English national cohort. It was hypothesised that early-onset BP (age <18 years) is a more severe form of the disorder, with a more rapid, and higher rate of conversion from depression to BP.

METHOD

This record linkage study used English national Hospital Episode Statistics (HES) covering all NHS inpatient and day case admissions between 1999 and 2011.

RESULTS

The overall rate of conversion from depression to BP for all ages was 5.65% (95% CI: 5.48-5.83) over a minimum 4-year follow-up period. The conversion rate from depression to BP increased in a linear manner with age from 10-14 years - 2.21% (95% C: 1.16-4.22) to 30-34 years - 7.06% (95% CI: 6.44-7.55) (F1,23=77.6, p=0.001, R(2)=0.77). The time to conversion was constant across the age range. The rate of conversion was higher in females (6.77%; 95% CI: 6.53-7.02) compared to males, (4.17%; 95% CI: 3.95-4.40) (χ(2)=194, p<0.0001), and in those with psychotic depression 8.12% (95% CI: 7.65-8.62) compared to non-psychotic depression 5.65% (95% CI: 5.48-5.83) (χ(2)=97.0, p<0.0001).

LIMITATIONS

The study was limited to hospital discharges and diagnoses were not standardised.

CONCLUSIONS

Increasing conversion rate from depression to bipolar disorder with age, and constant time for conversion across the age range does not support the notion that early-onset BP is a more severe form of the disorder.

Excessive mood elevation and behavioral activation with antidepressant treatment of juvenile depressive and anxiety disorders: a systematic review

BACKGROUND

The prevalence, characteristics and implications of excessive arousal-activation in children and adolescents treated with antidepressants for specific illnesses have not been systematically examined.

METHODS

We compared reports of antidepressant trials (n = 6,767 subjects) in juvenile depressive (n = 17) and anxiety disorders (n = 25) for consensus-based indications of psychopathological mood elevation or behavioral activation.

RESULTS

Rates of excessive arousal-activation during treatment with antidepressants were at least as high in juvenile anxiety (13.8%) as depressive (9.79%) disorders, and much lower with placebos (5.22 vs. 1.10%, respectively; both p < 0.0001). The antidepressant/placebo risk ratio for such reactions in paired comparisons was 3.50 (12.9/3.69%), and the meta-analytically pooled rate ratio was 1.7 (95% confidence interval: 1.2-2.2; both p ≤ 0.001). Overall rates for 'mania or hypomania', specifically, were 8.19% with and 0.17% without antidepressant treatment, with large drug/placebo risk ratios among depressive (10.4/0.45%) and anxiety (1.98/0.00%) disorder patients.

CONCLUSIONS

Risks of excessive mood elevation during antidepressant treatment, including mania-hypomania, were much greater than with placebo, and similar in juvenile anxiety and depressive disorders. Excessive arousal-activation in children or adolescents treated with antidepressants for anxiety as well as depressive disorders calls for particular caution and monitoring for potential risk of future bipolar disorder.

Antidepressant-associated mood-switching and transition from unipolar major depression to bipolar disorder: a review

OBJECTIVES

Compare reported rates of mood-shifts from major depression to mania/hypomania/mixed-states during antidepressant (AD)-treatment and rates of diagnostic change from major depressive disorder (MDD) to bipolar disorder (BPD).

METHODS

Searching computerized literature databases, followed by summary analyses.

RESULTS

In 51 reports of patients diagnosed with MDD and treated with an AD, the overall risk of mood-switching was 8.18% (7837/95,786) within 2.39 ± 2.99 years of treatment, or 3.42 (95% CI: 3.34-3.50) %/year. Risk was 2.6 (CI: 2.5-2.8) times greater with/without AD-treatment by meta-analysis of 10 controlled trials. Risk increased with time up to 24 months of treatment, with no secular change (1968-2012). Incidence rates were 4.5 (CI: 4.1-4.8)-times greater among juveniles than adults (5.62/1.26 %/year; p<0.0001). In 12 studies the overall rate of new BPD-diagnoses was 3.29% (1928/56,754) within 5.38 years (0.61 [0.58-0.64] %/year), or 5.6-times lower (3.42/0.61) than annualized rates of mood-switching.

CONCLUSIONS

AD-treatment was associated with new mania-like responses in 8.18% of patients diagnosed with unipolar MDD. Contributions to mood-switching due to unrecognized BPD versus mood-elevating pharmacological effects, as well as quantitative associations between switching and later diagnosis of BPD not associated with AD-treatment remain uncertain.

LIMITATIONS

Rates and definitions of mood-switching with ADs varied greatly, exposure-times rarely were precisely defined, and there was little information on predictive associations between mood-switches and BPD-diagnosis.

Effectiveness and tolerability of citalopram for the treatment of depression and anxiety disorders in children and adolescents: an open-label study

To assess the effectiveness and tolerability of citalopram for the acute treatment of children and adolescents suffering from depression and/or anxiety disorders. As much as 78 outpatients, aged 7-18 years with a diagnosis of depressive and/or anxiety disorder, completed an 8-week open trial with citalopram (20-40 mg/day). Outcome, side effects and suicidality were assessed weekly to bi-weekly using appropriate rating scales. At endpoint 56% of subjects were found to be responders (Clinical Global Impression-Improvement [CGI-I] Scale <or= 2). Subjects with less severe psychopathology and subjects with anxiety disorders showed a more favorable response. As much as 43% of depressed and 51% of anxious subjects had a 50% or greater reduction in scores on our secondary outcome measures, Children's Depression Rating Scale-Revised (CDRS-R) and Screen for Child Anxiety Related Emotional Disorders (SCARED). Most reported adverse events were mild to moderate and did not affect medication adherence. No increase in suicidality was observed during the study. Citalopram was moderately effective, generally well tolerated and safe for the acute treatment of depressed and anxious children and adolescents.

Duloxetine-induced hypomania: case report and brief review of the literature on SNRIs-induced mood switching

Manic switching during antidepressant treatment has been reported with every class of antidepressant drugs. Serotonin-noradrenaline reuptake inhibitors (SNRIs) have been increasingly used for the treatment of unipolar and bipolar depression and are well tolerated and sufficiently effective because of their dual mechanism of action. A case of duloxetine-induced hypomania in a non-bipolar patient is presented, and a brief review of all cases of SNRIs' induced mania and hypomania has been carried out. The available data suggest that SNRIs, especially venlafaxine, can induce mood switching in patients with bipolar depression and in certain patients with unipolar depression, but the potential of duloxetine and milnacipran to induce manic or hypomanic symptoms cannot be disregarded. Switching appears to be dose-related and treatment initiation with lower doses and upward titration when needed may be preferable in selected cases and may help minimizing the risk of mood switching.

Psychopharmacologic treatment of pediatric major depressive disorder

RATIONALE

The role of pharmacotherapy in the treatment of major depressive disorder (MDD) in youth has received much attention in recent years due to concerns of efficacy and safety of the antidepressants for the treatment of MDD in youth.

OBJECTIVES

This review describes the existing published and unpublished literature regarding the efficacy and short-term safety of the antidepressants and decision-making process required for the use of these medications for youth with MDD. In addition, current continuation and maintenance treatments are discussed.

RESULTS

In general, nine depressed youth must be treated with an antidepressant to obtain one clinical response above that achieved with placebo. To date, fluoxetine has showed the most consistent positive treatment effects. Depressed youth had also acutely responded to other antidepressants, but the response to placebo has also been high. Overall, the antidepressants are well tolerated, but 1-3 children and adolescents of 100 taking antidepressants showed onset or worsening of suicidal ideation and, more rarely, suicide attempts.

CONCLUSIONS

There is a positive risk-benefit ratio for the use of antidepressants in the acute treatment of depressed youth. First-line antidepressant treatment with-or without-specific types of psychotherapy is indicated for youth with MDD of at least moderate severity. All youth taking antidepressants must be closely monitored for suicidality and medication side effects. Many youth will likely require psychotherapy or additional medication treatments to address comorbid disorders. Treatments to prevent relapses and recurrences require further study.

Antidepressants and suicidal behavior in bipolar disorder

Patients with bipolar disorder are at very high risk for suicidal ideation, non-fatal suicidal behaviors and suicide and are frequently treated with antidepressants. However, no prospective, randomized, controlled study specifically evaluating an antidepressant on suicidality in bipolar disorder has yet been completed. Indeed, antidepressants have not yet been shown to reduce suicide attempts or suicide in depressive disorders and may increase suicidal behavior in pediatric, and possibly adult, major depressive disorder. Available data on the effects of antidepressants on suicidality in bipolar disorder are mixed. Considerable research indicates that mixed states are associated with suicidality and that antidepressants, especially when administered as monotherapy, are associated with both suicidality and manic conversion. In contrast, growing research suggests that antidepressants administered in combination with mood stabilizers may reduce depressive symptoms in patients with bipolar depression. Further, the only prospective, long-term study evaluating antidepressant treatment and mortality in bipolar disorder, although open-label, found antidepressants and/or antipsychotics in combination with lithium, but not lithium alone, reduced suicide in bipolar and unipolar patients (Angst F, et al. J Affect Disord 2002: 68: 167-181). We conclude that antidepressants may induce suicidality in a subset of persons with depressive (and probably anxious) presentations; that this induction may represent a form of manic conversion, and hence a bipolar phenotype, and that lithium's therapeutic properties may include the ability to prevent antidepressant-induced suicidality.