ECT augmentation of clozapine for clozapine-resistant schizophrenia: A meta-analysis of randomized controlled trials

Predicting responses to electroconvulsive therapy in schizophrenia patients undergoing antipsychotic treatment: Baseline functional connectivity among regions with strong electric field distributions

This study explored imaging predictors of electroconvulsive therapy (ECT) outcome in schizophrenia patients based on pre-treatment functional connectivity (FC) within regions with strong ECT electric fields distribution. Forty-seven patients received standard antipsychotic drugs combined with ECT as well as two brain imaging sessions. Regions of interest (ROI) with strong electric field distribution were determined by ECT simulation. Using baseline functional connectivity between ROIs, a model was constructed to predict the percentage reduction of Positive and Negative Syndrome Scale (PANSS) scores. The strong electric fields were distributed in the orbital prefrontal lobe, medial temporal lobe, and other parts of the temporal lobe. Ten functional connectivity features within the electric field distribution areas showed a predictive ability for ECT outcome. The correlation coefficient between the predictive and real values of cross-validation was 0.7165. Among the predictive features, ECT induced a significant decrease in functional connectivity between the right amygdala and the left hippocampus. These results suggest that pretreatment functional connectivity patterns in brain regions with strong electric field distributions during ECT could be potential predictors of the efficacy of ECT augmentation in schizophrenia. These findings may help to improve individualized clinical treatment in the future.

Clozapine Combination and Augmentation Strategies in Patients With Schizophrenia -Recommendations From an International Expert Survey Among the Treatment Response and Resistance in Psychosis (TRRIP) Working Group

BACKGROUND

Evidence for the management of inadequate clinical response to clozapine in treatment-resistant schizophrenia is sparse. Accordingly, an international initiative was undertaken with the aim of developing consensus recommendations for treatment strategies for clozapine-refractory patients with schizophrenia.

METHODS

We conducted an online survey among members of the Treatment Response and Resistance in Psychosis (TRRIP) working group. An agreement threshold of ≥75% (responses "agree" + "strongly agree") was set to define a first-round consensus. Questions achieving agreement or disagreement proportions of >50% in the first round, were re-presented to develop second-round final consensus recommendations.

RESULTS

Forty-four (first round) and 49 (second round) of 63 TRRIP members participated. Expert recommendations at ≥75% agreement included raising clozapine plasma levels to ≥350 ng/ml for refractory positive, negative, and mixed symptoms. Where plasma level-guided dose escalation was ineffective for persistent positive symptoms, waiting for a delayed response was recommended. For clozapine-refractory positive symptoms, combination with a second antipsychotic (amisulpride and oral aripiprazole) and augmentation with ECT achieved consensus. For negative symptoms, waiting for a delayed response was recommended, and as an intervention for clozapine-refractory negative symptoms, clozapine augmentation with an antidepressant reached consensus. For clozapine-refractory suicidality, augmentation with antidepressants or mood-stabilizers, and ECT met consensus criteria. For clozapine-refractory aggression, augmentation with a mood-stabilizer or antipsychotic medication achieved consensus. Generally, cognitive-behavioral therapy and psychosocial interventions reached consensus.

CONCLUSIONS

Given the limited evidence from randomized trials of treatment strategies for clozapine-resistant schizophrenia (CRS), this consensus-based series of recommendations provides a framework for decision making to manage this challenging clinical situation.

A Rational Use of Clozapine Based on Adverse Drug Reactions, Pharmacokinetics, and Clinical Pharmacopsychology

Using Richardson and Davidson's model and the sciences of pharmacokinetics and clinical pharmacopsychology, this article reviewed the: (1) poor life expectancy associated with treatment-resistant schizophrenia (TRS), which may be improved in patients who adhere to clozapine; (2) findings that clozapine is the best treatment for TRS (according to efficacy, effectiveness and well-being); and (3) potential for clozapine to cause vulnerabilities, including potentially lethal adverse drug reactions such as agranulocytosis, pneumonia, and myocarditis. Rational use requires: (1) modification of the clozapine package insert worldwide to include lower doses for Asians and to avoid the lethality associated with pneumonia, (2) the use of clozapine levels for personalizing dosing, and (3) the use of slow and personalized titration. This may make clozapine as safe as possible and contribute to increased life expectancy and well-being. In the absence of data on COVID-19 in clozapine patients, clozapine possibly impairs immunological mechanisms and may increase pneumonia risk in infected patients. Psychiatrists should call their clozapine patients and families and explain to them that if the patient develops fever or flu-like symptoms, the psychiatrist should be called and should consider halving the clozapine dose. If the patient is hospitalized with pneumonia, the treating physician needs to assess for symptoms of clozapine intoxication since halving the dose may not be enough for all patients; consider decreasing it to one-third or even stopping it. Once the signs of inflammation and fever have disappeared, the clozapine dose can be slowly increased to the prior dosage level.

[Pharmacotherapy of schizophrenia]

BACKGROUND

Schizophrenia is a severe psychiatric disorder with variable therapeutic responses, the etiology and pathophysiology of which require further elucidation.

OBJECTIVE

To review which pharmacological options are effective and safe and for which treatment goals in schizophrenia.

MATERIAL AND METHODS

Narrative review of the pharmacological therapy of adults diagnosed with schizophrenia.

RESULTS

Despite heterogeneous therapeutic responses, to date only dopamine antagonists or partial agonists are approved for the treatment of schizophrenia. The efficacy of antipsychotic agents differs only gradually, with the exception of clozapine for treatment-resistant schizophrenia, whereas undesired adverse effects are more variable. Those antipsychotic agents that show gradual efficacy advantages in meta-analyses of acute and maintenance treatment (clozapine, amisulpride, olanzapine, risperidone) are also those where at least one undesired adverse effect is most severely expressed. Antipsychotic adverse effects occur in subgroups of patients and are generally tolerable or treatable, whereas the "side effect" of untreated schizophrenia affects almost all patients, including relapses, psychosocial deterioration, secondary treatment resistance and increased mortality. Therefore, in patients with a confirmed diagnosis of schizophrenia, a lifelong continuous therapy is currently most likely indicated, ideally with antipsychotic agents for which adherence is directly measurable and improved. In the case of treatment resistant clozapine is the agent of choice, followed by electroconvulsive therapy, which also has the best evidence as augmentation treatment in cases of clozapine resistance.

CONCLUSION

New therapeutic agents with improved efficacy and tolerability as well as effectiveness for negative symptoms and cognitive disturbance are needed.

The neurobiology of treatment-resistant schizophrenia: paths to antipsychotic resistance and a roadmap for future research

Treatment-resistant schizophrenia (TRS), the persistence of positive symptoms despite ≥2 trials of adequate dose and duration of antipsychotic medication with documented adherence, is a serious clinical problem with heterogeneous presentations. TRS can vary in its onset (at the first episode of psychosis or upon relapse), in its severity, and in the response to subsequent therapeutic interventions (i.e., clozapine, electroconvulsive therapy). The heterogeneity of TRS indicates that the underlying neurobiology of TRS may differ not only from treatment-responsive schizophrenia but also among patients with TRS. Several hypotheses have been proposed for the neurobiological mechanisms underlying TRS, including dopamine supersensitivity, hyperdopaminergic and normodopaminergic subtypes, glutamate dysregulation, inflammation and oxidative stress, and serotonin dysregulation. Research supporting these hypotheses is limited in part by variations in the criteria used to define TRS, as well as by the biological and clinical heterogeneity of TRS. Clinical trial designs for new treatments should be informed by this heterogeneity, and further clinical research is needed to more clearly understand the underlying neurobiology of TRS and to optimize treatment for patients with TRS.

Serum BDNF Levels are Not Associated with the Antidepressant Effects of Nonconvulsive Electrotherapy

OBJECTIVE

Brain-derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of depression and in the antidepressant response. This study examined whether changes in serum BDNF levels are associated with the antidepressant effects of nonconvulsive electrotherapy (NET).

METHODS

For BDNF analyses, serum samples were collected from 20 patients with treatment-refractory depression (TRD) and from 20 healthy controls. Serum samples were also collected from patients following a course of NET.

RESULTS

Although significantly lower baseline serum BDNF levels were observed in TRD patients than in healthy controls, no changes in serum BDNF levels were found in TRD patients after a course of NET compared to baseline. No significant association was found between serum BDNF levels and depression severity.

CONCLUSION

Serum BDNF levels appear to have no clinical utility in the prediction of the antidepressant effects of NET in patients with TRD. Future studies of higher quality and with larger sample sizes are needed to confirm these findings.

Clozapine augmentation strategies

Clozapine is established as the gold standard for antipsychotic treatment of patients suffering from treatment-resistant schizophrenia. Over virtually 3 decades, the level of inadequate response to clozapine was found to range from 40% to 60%. A heightened interest developed in the augmentation of clozapine to try to achieve response or maximize partial response. A large variety of drug groups have been investigated. This article focuses on the meta-analyses of these trials to discover reasonable evidence-based approaches to the management of patients not responding to clozapine.

Clinical Course, Neurobiology and Therapeutic Approaches to Treatment Resistant Schizophrenia. Toward an Integrated View

Despite considerable psychotherapeutic advancement since the discovery of chlorpromazine, almost one third of patients with schizophrenia remain resistant to dopamine-blocking antipsychotics, and continue to be exposed to unwanted and often disabling side effects, but little if any clinical benefit. Even clozapine, the superior antipsychotic treatment, is ineffective in approximately half of these patients. Thus treatment resistant schizophrenia (TRS), continues to present a major therapeutic challenge to psychiatry. The main impediment to finding novel treatments is the lack of understanding of precise molecular mechanisms leading to TRS. Not only has the neurobiology been enigmatic for decades, but accurate and early detection of patients who are at risk of not responding to dopaminergic blockade remains elusive. Fortunately, recent work has started to unravel some of the neurobiological mechanisms underlying treatment resistance, providing long awaited answers, at least to some extent. Here we focus on the scientific advances in the field, from the clinical course of TRS to neurobiology and available treatment options. We specifically emphasize emerging evidence from TRS imaging and genetic literature that implicates dysregulation in several neurotransmitters, particularly dopamine and glutamate, and in addition genetic and neural alterations that concertedly may lead to the formation of TRS. Finally, we integrate available findings into a putative model of TRS, which may provide a platform for future studies in a bid to open the avenues for subsequent development of effective therapeutics.

Can the Positive and Negative Syndrome scale (PANSS) differentiate treatment-resistant from non-treatment-resistant schizophrenia? A factor analytic investigation based on data from the Pattern cohort study

Treatment-Resistant Schizophrenia (TRS) and Non-Treatment-Resistant Schizophrenia (NTRS) may represent different subtypes of schizophrenia. However, few studies have investigated their PANSS symptom dimensions by Exploratory (EFA) or Confirmatory (CFA). Data from the present study are derived from 1429 patients of the Pattern study. TRS was defined by the use of clozapine in the previous year whereas NTRS by the use of non-clozapine antipsychotics ("by proxy"). Factors were chosen based on the Kaiser criterion and considered valid when loadings were greater than or equal to 0.5. The fit to the data was evaluated by CFA in comparison with well-established PANSS models, using fit indexes. The EFA yielded similar five-factor model in both groups: Negative, Positive, Anxiety/Depression, Cognitive and Excited. CFA showed a satisfactory, but not perfect, fit to the data, as compared with the previous PANSS factor analytic models. Despite the limitations regarding the 'by proxy' definition of TRS, the results of the present study show that there are no differences in the factorial structure of PANSS in patients with TRS and NTRS.

Electroconvulsive Therapy and Schizophrenia: A Systematic Review

Electroconvulsive therapy (ECT) is a remarkably effective treatment for major depressive disorder, but is less commonly utilized for treatment of psychotic disorders. Recent literature indicates that ECT can be a useful strategy for a wide range of psychotic disorders, including treatment-resistant schizophrenia. The purpose of this review is to examine the extant literature on ECT in schizophrenia with a primary focus on its efficacy, its impact on cognitive function, the role of maintenance ECT, and the potential role of neuroimaging biomarkers to provide more precise ECT treatment strategies. We evaluated the available literature, with a particular focus on prospective, randomized trials. Our review suggests that ECT can be an effective treatment strategy in this severely ill patient population. Studies suggest that while ECT in schizophrenia is a safe treatment modality, the potential for cognitive impairment must always be carefully weighed. The use and investigation of new biomarker strategies for the pharmacological treatment of schizophrenia, and the extension of these approaches to ECT are also discussed.

Exploration of Treatment-Resistant Schizophrenia Subtypes Based on a Survey of 204 US Psychiatrists

OBJECTIVE

To explore and describe potential subgroups within the treatment-resistant schizophrenia (TRS) population, using data from a survey of US psychiatrists.

METHODS

Psychiatrists completed an online survey of demographic/clinical characteristics and treatment history for two of their patients with TRS. Patients were stratified according to number of suicide attempts, number of hospitalizations, employment status, and TRS onset time frame.

RESULTS

Of the 408 patients with TRS described by psychiatrists, 37.5% had ≥1 suicide attempt, 78.9% had ≥2 hospitalizations, 74.5% were unemployed, 45.0% had TRS onset within 5 years of first treatment (a further 8.0% had TRS from first treatment), and 31.5% had TRS onset after 5 years (15.5% unknown). Patients with ≥1 (vs 0) suicide attempts had statistically significantly more psychiatric (3.6 vs 2.2) and physical (2.2 vs 1.6) comorbidities. Patients with ≥2 (vs ≤1) hospitalizations were statistically significantly more likely to have hallucinations, conceptual disorganization, social withdrawal, and cognitive dysfunction, and had more psychiatric (3.0 vs 1.9) and physical (2.0 vs 1.1) comorbidities. Unemployed (vs employed) patients were statistically significantly more likely to have delusions, hallucinations, blunted affect, social withdrawal, and cognitive dysfunction, and had more psychiatric (2.9 vs 2.3) and physical (2.1 vs 1.2) comorbidities. Patients with TRS onset ≤5 (vs >5) years were statistically significantly younger (35.0 vs 43.7 years), less likely to have hallucinations and social withdrawal, and had fewer psychiatric (2.6 vs 3.3) and physical (1.7 vs 2.3) comorbidities.

CONCLUSIONS

Greater clinical burden in TRS is associated with greater illness severity and chronicity markers, suggesting a dimensional gradient from non-TRS to mild-moderate and more severe forms of TRS. Time to onset of TRS may have implications for outcomes, with data indicating greater burden in those with late-onset TRS. Accumulation of illness over time may be more important than time to onset.