Dopamine sudden depletion as a model for mixed depression

Mood and behavior regulation: interaction of lithium and dopaminergic system

Lithium is one of the most effect mood-stabilizing drugs prescribed especially for bipolar disorder. Lithium has wide range effects on different molecular factors and neural transmission including dopaminergic signaling. On the other hand, mesolimbic and mesocortical dopaminergic signaling is significantly involved in the pathophysiology of neuropsychiatric disorders. This review article aims to study lithium therapeutic mechanisms, dopaminergic signaling, and the interaction of lithium and dopamine. We concluded that acute and chronic lithium treatments often reduce dopamine synthesis and level in the brain. However, some studies have reported conflicting results following lithium treatment, especially chronic treatment. The dosage, duration, and type of lithium administration, and the brain region selected for measuring dopamine level were not significant differences in different chronic treatments used in previous studies. It was suggested that lithium has various mechanisms affecting dopaminergic signaling and mood, and that many molecular factors can be involved, including brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB), β-catenin, protein kinase B (Akt), and glycogen synthase kinase-3 beta (GSK-3β). Thus, molecular effects of lithium can be the most important mechanisms of lithium that also alter neural transmissions including dopaminergic signaling in mesolimbic and mesocortical pathways.

Ralentissement psychomoteur et trouble bipolaire

La dimension thymique est souvent considérée – à juste titre – comme centrale dans les différentes phases observées dans les troubles bipolaires de l’humeur. Mais au-delà, une autre dimension, plus psychomotrice, apparaît comme un outil de description sémiologique des états dépressifs, (hypo)manes et mixtes et des phases dites de rémission. La mesure de cette dimension psychomotrice peut faire appel à des questionnaires, des tests neuropsychologiques ou des outils d’utilisation plus récente dans le domaine des troubles bipolaires comme l’actigraphie par exemple. Nous montrerons que ces différents outils permettent de modéliser les différents états de la pathologie comme des défauts d’inhibition/activation avec différents outputs comportementaux ou cognitifs. Ces mesures permettraient par exemple de distinguer les dépressions « pures » anergiques/hypo-actives des dépressions avec composante de mixité, toutes deux observées dans le cours évolutif des troubles bipolaires. Elles permettraient aussi potentiellement d’orienter le diagnostic vers des troubles unipolaires ou d’identifier des dimensions de bipolarité. Enfin, ces dimensions d’inhibition/activation pourraient relancer le débat autour de la place centrale de la dopamine comme ces différents états des troubles bipolaires. Certains modèles récents proposent notamment la notion de « déplétion soudaine » en dopamine pour expliquer les transitions entre divers états des troubles bipolaires, caractérisés pour les uns par le ralentissement psychomoteur et ou les autres par une sur-activation psychomotrice. Nous ouvrirons les perspectives sur les possibles usages des agonistes dopaminergiques dans la prise en charge des dépressions bipolaires, alors que ces traitements ont été jusqu’à récemment considérés comme contre-indiqués du fait des risques d’inversion de l’humeur.

Subjective response to antipsychotics in bipolar disorders: A review of a neglected area

Background:

The term “subjective response to antipsychotic” (SRA) refers to changes in the subjective state experienced due to antipsychotic (AP) exposition that is independent of the therapeutic or physical side effects of these drugs. This dimension of analysis has been extensively explored in schizophrenic disorders, finding that negative SRA is an early and independent predictor of compliance as well as a successful pathway to construct current theoretical frameworks of these disorders. There is an increasing use of AP in bipolar disorders’ treatment (BD) but no reviews on the topic have been published to date in this population. The aim of this work is to review published data of SRA in BD patients and to discuss their clinical and theoretical implications.

Methods:

An extensive search in online databases was performed. Reports were reviewed and included if they described SRA in BD or included instruments aimed to assess it. Reports of cognitive, sexual, motor autonomic side effects were excluded. Findings were summarized in a narrative fashion.

Results:

Nine reports fulfilled the inclusion criteria and were included in the revision, reporting data from 1282 BD patients. Among these, three were prospective studies and three explored relations between SRA and treatment compliance.

Conclusions:

There is an asymmetry between the increase in the use of antipsychotics in BD and the lack of data regarding the SRA. Phenomenologically, SRA in BD is similar to that found in schizophrenic subjects. Some of these symptoms may be misdiagnosed as depressive symptoms. The existing data show that SRA has a strong correlation with treatment compliance as well as a promising way to develop theoretical paradigms for these disorders.

The Potential Utility of Aripiprazole Augmentation for Major Depressive Disorder with Mixed Features Specifier: A Retrospective Study

Objective

The present study aimed to observe potential benefit of aripiprazole augmentation in the treatment of major depressive disorder with mixed specifier (MDDM) in naturalistic treatment setting.

Methods

Data were collected from MDDM patients using a retrospective chart review for 8 weeks (week –8 and week 0) in routine practice. All patients were on current antidepressants upon starting of aripiprazole. Patients were treated without restriction of doses of aripiprazole. The primary endpoint was the mean change of Montgomery–Åsberg Depression Rating Scale (MADRS) total scores along with various secondary endpoint measures.

Results

In total 38 patients were analyzed. The changes of MADRS, Clinical Global Impression (CGI)-severity, Young Mania Rating Scale, Sheehan Disability Scale, and CGI-clinical benefit total scores from baseline to the endpoint were −7.1, −0.8, −4.9, −4.1, and −3.6, respectively (all p < 0.0001). At the endpoint, the responder and remitter rates by MADRS score criteria were approximately 32% and 21%, respectively.

Conclusion

The present findings have clearly shown the effectiveness and tolerability of aripiprazole augmentation for MDDM patients in routine practice. The present study warrants subsequent, adequately-powered, well-controlled studies for generalizability near future.

Dopaminergic agents in the treatment of bipolar depression: a systematic review and meta-analysis

OBJECTIVE

To systematically examine the effects of dopaminergic agents (modafinil, armodafinil, pramipexole, methylphenidate, and amphetamines) on bipolar depression outcomes.

METHODS

Meta-analysis of randomized controlled trials was performed to assess the efficacy and safety of treatment with dopaminergic agents in bipolar depression. In a secondary analysis, findings from both randomized controlled trials and high-quality observational studies were pooled by means of meta-analytic procedures to explore dopaminergic treatment-related new mania.

RESULTS

Nine studies (1716 patients) were included in our meta-analysis of randomized controlled trials. Treatment with dopaminergic agents for bipolar depression was associated with an increase in both response (1671 individuals, RR 1.25, 95% CI 1.05 to 1.50) and remission rates (1671 individuals, RR 1.40, 95% CI 1.14, 1.71). There was no evidence of an increased risk of mood switch associated with this treatment (1646 individuals, RR 0.96, 95% CI 0.49, 1.89). Our secondary analysis (1231 individuals) yielded a cumulative incidence of mood switch of 3% (95% CI 1.0, 5.0) during a mean follow-up period of 7.5 months.

CONCLUSIONS

Preliminary findings suggest that dopaminergic agents may represent a useful alternative for the treatment of bipolar depression, with no evidence for a related increase in the risk of mood destabilization during short-term follow-up.

Interaction between COMT rs5993883 and second generation antipsychotics is linked to decreases in verbal cognition and cognitive control in bipolar disorder

BACKGROUND

Second generation antipsychotics (SGAs) are increasingly utilized in Bipolar Disorder (BD) but are potentially associated with cognitive side effects. Also linked to cognitive deficits associated with SGA-treatment are catechol-O-methyltransferase (COMT) gene variants. In this study, we examine the relationship between cognition in SGA use and COMT rs5993883 in cohort sample of subjects with BD.

METHODS

Interactions between SGA-treatment and COMT rs5993883 genotype on cognition was tested using a battery of neuropsychological tests performed in cross-sectional study of 246 bipolar subjects.

RESULTS

The mean age of our sample was 40.15 years and was comprised of 70 % female subjects. Significant demographic differences included gender, hospitalizations, benzodiazepine/antidepressant use and BD-type diagnosis. Linear regressions showed that the COMT rs5993883 GG genotype predicted lower verbal learning (p = 0.0006) and memory (p = 0.0026) scores, and lower scores on a cognitive control task (p = 0.004) in SGA-treated subjects. Interestingly, COMT GT- or TT-variants showed no intergroup cognitive differences. Further analysis revealed an interaction between SGA-COMT GG-genotype for verbal learning (p = 0.028), verbal memory (p = 0.026) and cognitive control (p = 0.0005).

CONCLUSIONS

This investigation contributes to previous work demonstrating links between cognition, SGA-treatment and COMT rs5993883 in BD subjects. Our analysis shows significant associations between cognitive domains such as verbal-cognition and cognitive control in SGA-treated subjects carrying the COMT rs5993883 GG-genotype. Prospective studies are needed to evaluate the clinical significance of these findings.

Behavioral and emotional adverse events of drugs frequently used in the treatment of bipolar disorders: clinical and theoretical implications

BACKGROUND

Behavioral and emotional adverse events induced by drugs commonly prescribed to patients with bipolar disorders are of paramount importance to clinical practice and research. However, no reviews on the topic have been published so far.

METHODS

An extensive search was performed. Reports were reviewed if they described behavioral side effects related to pharmacological treatments for bipolar disorders in healthy subjects or patients with different neuropsychiatric disorders. For this review, lithium, antipsychotics, anticonvulsants and selective serotonin reuptake inhibitors were included.

RESULTS

Apathy or emotional blunting, diminished sexual desire, and inability to cry were reported to be associated with exposure to selective serotonin reuptake inhibitors. Neuroleptic-induced deficit syndrome/emotional detachment and obsessive-compulsive symptomatology and decision-making modifications. A lithium-related amotivational syndrome was also reported in the literature. Furthermore, hypersexuality and obsessive-compulsive symptoms have been noted in subjects treated with lamotrigine.

LIMITATIONS

Primary studies on drug-related adverse events are scant so far and most of the data currently available derive from case reports. Moreover, most of the evidence reviewed is based on studies performed on healthy subjects and patients with neuropsychiatric conditions other than bipolar disorders.

DISCUSSION

There is a remarkable dearth of data on behavioral adverse events of pharmacological treatment for bipolar disorders. However, the pieces of evidence available at present, though scant and scattered, suggest that different behavioral adverse events may be related to pharmacological treatment for these disorders. The implications of these findings for research and management of patients with mood disorders are discussed.

Depression and impulsivity as pathways to violence: implications for antiaggressive treatment

BACKGROUND

Difficulties with affect regulation and impulse control have a strong influence on violence. The objective of this study was to determine whether baseline depression and impulsivity predict aggression and whether they predict differential response to antiaggressive treatment. This is important, as we lack knowledge as to the selection of antipsychotics for the treatment of aggression.

METHODS

Physically aggressive inpatients with schizophrenia who received an evaluation of depression and impulsivity at baseline were randomly assigned in a double-blind, parallel group, 12-week trial to clozapine, olanzapine, or haloperidol. Trait impulsivity was measured by the Barratt Impulsiveness Scale; depression by the Positive and Negative Syndrome Scale Depression factor. The number and severity of aggressive events, as measured by the Modified Overt Aggression Scale (MOAS), were the outcome measures.

RESULTS

Baseline depression and impulsivity predicted higher levels of aggression, as measured by the MOAS total score, over the 12-week treatment period across all 3 medication groups. In addition, there was a strong interaction effect between baseline depression/impulsivity and medication grouping in predicting MOAS score. In particular, when higher depression and impulsivity were present at baseline, patients on haloperidol presented with more aggression than patients on the other 3 medications.

CONCLUSIONS

Depression and impulsivity are important predictors of aggression and of differential response to antiaggressive treatment. This is most likely due to the medications' dissimilar neurotransmitter profiles. By identifying patients who will respond better to a given medication, we will be able to develop individualized strategies for the treatment of violent behavior.