Electroconvulsive therapy augmentation in clozapine-resistant schizophrenia: a prospective, randomized study

Cortical electroconvulsive stimulation alleviates breeding-induced prepulse inhibition deficit in rats

In patients with medical-refractory schizophrenia electroconvulsive therapy (ECT), i.e., the induction of therapeutic seizures via cortical surface electrodes, is effectively used. Electroconvulsive stimulation (ECS) in rodents simulates ECT in humans and is applied to investigate the mechanisms underlying this treatment. Experimentally-induced reduced prepulse inhibition (PPI) of the acoustic startle response (ASR), i.e., the reduction of the startle response to an intense acoustic stimulus when this stimulus is shortly preceded by a weaker not-startling stimulus, serves as an endophenotype for neuropsychiatric disorders that are accompanied by disturbed sensorimotor gating, such as schizophrenia. Here we used rats selectively bred for high and low PPI to evaluate whether bifrontal cortical ECS would affect PPI. For this purpose, cortical screw electrodes were stereotactically implanted above the frontal cortex. After recovery ECS was applied for five consecutive days with stimuli of 1 ms pulse-width, 100 pulses/s, 1 s duration, ranging from 5.5 mA to 10 mA. PPI of ASR was measured one day before ECS, and on days 1, 7, and 14 after the last ECS. In rats with breeding-induced low PPI ECS increased PPI one week after stimulation. In contrast, ECS decreased PPI in rats with high PPI on the first day after stimulation. The reaction to the startle impulse was reduced by ECS without difference between groups. This work provides evidence that rats with breeding-induced high or low PPI could be used to further investigate the underlying mechanisms of ECT in neuropsychiatric disorders with disturbed sensorimotor gating like schizophrenia.

Transcutaneous noninvasive vagus nerve stimulation (tVNS) in the treatment of schizophrenia: a bicentric randomized controlled pilot study

Despite many pharmacological and psychosocial treatment options, schizophrenia remains a debilitating disorder. Thus, new treatment strategies rooted in the pathophysiology of the disorder are needed. Recently, vagus nerve stimulation (VNS) has been proposed as a potential treatment option for various neuropsychiatric disorders including schizophrenia. The objective of this study was to investigate for the first time the feasibility, safety and efficacy of transcutaneous VNS in stable schizophrenia. A bicentric randomized, sham-controlled, double-blind trial was conducted from 2010 to 2012. Twenty schizophrenia patients were randomly assigned to one of two treatment groups. The first group (active tVNS) received daily active stimulation of the left auricle for 26 weeks. The second group (sham tVNS) received daily sham stimulation for 12 weeks followed by 14 weeks of active stimulation. Primary outcome was defined as change in the Positive and Negative Symptom Scale total score between baseline and week 12. Various other secondary measures were assessed to investigate safety and efficacy. The intervention was well tolerated with no relevant adverse effects. We could not observe a statistically significant difference in the improvement of schizophrenia psychopathology during the observation period. Neither psychopathological and neurocognitive measures nor safety measures showed significant differences between study groups. Application of tVNS was well tolerated, but did not improve schizophrenia symptoms in our 26-week trial. While unsatisfactory compliance questions the feasibility of patient-controlled neurostimulation in schizophrenia, the overall pattern of symptom change might warrant further investigations in this population.

Delayed initiation of clozapine may be related to poor response in treatment-resistant schizophrenia

The aim of this retrospective chart-review study was to investigate the relationship between delayed commencement of clozapine and the level of response in treatment-resistant schizophrenia (TRS). We included 162 patients with schizophrenia who used clozapine. The mean delay until starting clozapine after fulfillment of the TRS criteria was 29 months. The delay was shorter in those who gained benefit from clozapine (P=0.04), those who were treated in a specialized psychosis outpatient unit (P=0.01), and in men (P=0.009), and it correlated with age (P<0.001). The delay in starting clozapine and the maximum clozapine dose were independent contributors toward the response to clozapine in the logistic regression analysis. Moreover, of those who gained considerable benefit from clozapine, the patients were younger (P=0.01), the duration of illness before clozapine treatment was shorter (P=0.001), and the numbers of adequate antipsychotic trials before the use of clozapine were fewer (P=0.05). Our findings suggest that efforts aimed at reducing the delay for starting clozapine may increase the effectiveness of clozapine in TRS.

Neuromodulation Treatments for Schizophrenia

Schizophrenia is a psychiatric disorder that causes great suffering and debilitation worldwide. We have a multitude of medications that are effective for psychosis. However, these have not been successful in treating the negative and cognitive symptom domains of schizophrenia. These symptoms are responsible for the larger part of functional impairments that result from schizophrenia. In addition, there are many patients for whom no significant improvement is achieved even in the positive symptom domain. Hence, other treatment modalities have been explored to help these patients. Electroconvulsive therapy and transcranial magnetic stimulation are two of the most promising adjunct treatment methods for medication resistant schizophrenia. Electroconvulsive therapy is the gold standard treatment for catatonias whether associated with schizophrenia, mood disorders or other non-psychiatric disorders. Although not effective for negative symptoms, electroconvulsive therapy provides substantial augmentation to antipsychotic medications in improving positive symptoms and overall severity. Electroconvulsive therapy should be considered more often in patients with inadequate response to antipsychotic medications even when they do not have prominent affective symptoms. Transcranial magnetic stimulation has emerged as a promising useful therapeutic tool in targeting medication resistant auditory hallucinations and negative symptoms. Transcranial magnetic stimulation has proven to be very safe and well-tolerated by the patients in spite of its labor intensiveness. The incorporation of transcranial magnetic stimulation to routine clinical use awaits further studies to substantiate its efficacy and to optimize and customize treatment parameters to individual patients and their symptom patterns. Moreover, combining transcranial magnetic stimulation with electroconvulsive therapy to synergize their likely different mechanisms of action is another exciting possibility.

Combined use of clozapine and ECT: a review

OBJECTIVE

This paper aims to review the available evidence for the use of clozapine and electroconvulsive therapy (ECT) in combination.

METHODOLOGY

Electronic searches were carried out to identify reports describing the combined use of clozapine and ECT.

RESULTS

Forty reports including 208 patients were identified. The majority of reports were in the form of case reports and case series, with few retrospective and open-label studies. The majority of patients were aged between 18 and 65 years and diagnosed with schizophrenia or schizoaffective disorder. Most of the patients refractory to clozapine were started on ECT as an augmentation therapy; however, in some reports, both ECT and clozapine were started concurrently, and in few cases clozapine was started after ECT. In terms of effectiveness, 37.5-100% patients improved in short-term, and sustained long-term improvement (3 weeks to 24 months) was described in few studies. In terms of the side-effect profile, five patients each had delirium and tachycardia and only four patients were described to have prolonged seizures. Overall, the combination was considered effective and safe.

CONCLUSION

There is evidence for the effectiveness and safety of the clozapine-ECT combination and it should be used in patients with treatment-resistant schizophrenia who do not respond to clozapine.

Transcranial magnetic stimulation, transcranial direct current stimulation and electroconvulsive therapy for medication-resistant psychosis of schizophrenia

PURPOSE OF REVIEW

Despite adequate antipsychotic treatment, 20-30% of patients with schizophrenia fail to obtain remission from psychosis. Physical stimulation treatments may provide an alternative therapy. In this review, we summarize the most recent studies regarding repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS) and electroconvulsive therapy (ECT) for medication-resistant psychosis in schizophrenia.

RECENT FINDINGS

Stimulation techniques in the treatment of medication-resistant psychosis have shown inconsistent results. Initial results of rTMS for auditory verbal hallucinations (AVH) were promising, but three recent large randomized controlled trials (RCTs) show similar results of rTMS as placebo. tDCS has shown initial promise as a treatment for AVH, but only in case studies and in two small RCTs. Larger studies are needed to define its efficacy. Although psychotic symptoms generally decrease after ECT, its efficacy has not been demonstrated in comparison with placebo.

SUMMARY

Although previous meta-analyses indicate significant mean effect sizes for rTMS for intractable AVH, three recent large RCTs indicate no effect compared with placebo. The use of tDCS for resistant AVH and ECT for intractable psychosis has shown some initial promise, but adequately sized placebo-controlled RCTs are now needed. Taken together, the evidence for physical stimulation techniques to relieve medication-resistant psychosis is currently weak.

Schizophrenia: when clozapine fails

PURPOSE OF REVIEW

This article reviews the recent evidence for therapeutic strategies for patients with treatment-resistant schizophrenia (TRS) not responding to or only partially responding to clozapine.

RECENT FINDINGS

A number of pharmacological and nonpharmacological biological approaches for clozapine-resistant TRS have been evaluated in clinical trials. Among these, the evidence supporting clozapine augmentation by pharmacological approaches is weak and the reported benefits were modest at best. However, the results of a recent randomized trial suggest that electroconvulsive therapy (ECT) may be efficacious for the short-term treatment of patients with clozapine-resistant TRS.

SUMMARY

There is currently insufficient evidence for efficacy of pharmacological augmentation strategies to clozapine. ECT may be a promising option, but further research is necessary to confirm its long-term effects. Moreover, further controlled studies are warranted to clarify the potential of other biological and psychosocial approaches to serve as adjuvant treatments in patients with clozapine-resistant TRS.