A prospective multicenter assessor-blinded randomized controlled study to compare the efficacy of short versus long protocols of electroconvulsive therapy as an augmentation strategy to clozapine in patients with ultra-resistant schizophrenia (SURECT study)

Efficacy of Rivastigmine Augmentation on Positive and Negative Symptoms, General Psychopathology, and Quality of Life in Patients with Chronic Schizophrenia: A Randomized Controlled Trial

The study aimed to assess Rivastigmine augmentation on positive and negative symptoms (PNSs), general psychopathology, and quality of life in patients with chronic Schizophrenia. A double-blind, parallel-design, randomized, placebo-controlled trial of 60 schizophrenia patients was conducted. Intervention group received rivastigmine 3 mg/day + Treatment as Usual (TAU) and the control group: TAU + placebo. Negative and positive symptoms, general psychopathology; and quality of life were measured using Positive and Negative Symptom Scale (PANSS) and Manchester Short Assessment of Quality of Life (MANSA). T-test, ANOVA, and the general univariate linear model tests were used for the analyses. Out of 60 participants, 52 (86.6%) were male. At baseline, no significant relationship was found for demographic and clinical characteristics between intervention and control groups. Between-group analysis indicated that all outcome measures PNSs, general psychopathology symptoms, and QoL score in rivastigmine group was significantly improved (p = 0.001). According to within-group analysis, a significant association was found between Rivastigmine and placebo groups in PNSs (p < 0.05). Rivastigmine augmentation improved PNSs and psychopathology in schizophrenia patients. However, no significant association found for improving the life quality after 8 weeks treatment.

Neuropsychological differences between treatment-resistant and treatment-responsive schizophrenia: a meta-analysis

Antipsychotic treatment resistance affects up to a third of individuals with schizophrenia. Of those affected, 70-84% are reported to be treatment resistant from the outset. This raises the possibility that the neurobiological mechanisms of treatment resistance emerge before the onset of psychosis and have a neurodevelopmental origin. Neuropsychological investigations can offer important insights into the nature, origin and pathophysiology of treatment-resistant schizophrenia (TRS), but methodological limitations in a still emergent field of research have obscured the neuropsychological discriminability of TRS. We report on the first systematic review and meta-analysis to investigate neuropsychological differences between TRS patients and treatment-responsive controls across 17 published studies (1864 participants). Five meta-analyses were performed in relation to (1) executive function, (2) general cognitive function, (3) attention, working memory and processing speed, (4) verbal memory and learning, and (5) visual-spatial memory and learning. Small-to-moderate effect sizes emerged for all domains. Similarly to previous comparisons between unselected, drug-naïve and first-episode schizophrenia samples v. healthy controls in the literature, the largest effect size was observed in verbal memory and learning [dl = -0.53; 95% confidence interval (CI) -0.29 to -0.76; z = 4.42; p < 0.001]. A sub-analysis of language-related functions, extracted from across the primary domains, yielded a comparable effect size (dl = -0.53, 95% CI -0.82 to -0.23; z = 3.45; p < 0.001). Manipulating our sampling strategy to include or exclude samples selected for clozapine response did not affect the pattern of findings. Our findings are discussed in relation to possible aetiological contributions to TRS.

Clozapine: Why Is It So Uniquely Effective in the Treatment of a Range of Neuropsychiatric Disorders?

Clozapine is superior to other antipsychotics as a therapy for treatment-resistant schizophrenia and schizoaffective disorder with increased risk of suicidal behavior. This drug has also been used in the off-label treatment of bipolar disorder, major depressive disorder (MDD), and Parkinson's disease (PD). Although usually reserved for severe and treatment-refractory cases, it is interesting that electroconvulsive therapy (ECT) has also been used in the treatment of these psychiatric disorders, suggesting some common or related mechanisms. A literature review on the applications of clozapine and electroconvulsive therapy (ECT) to the disorders mentioned above was undertaken, and this narrative review was prepared. Although both treatments have multiple actions, evidence to date suggests that the ability to elicit epileptiform activity and alter EEG activity, to increase neuroplasticity and elevate brain levels of neurotrophic factors, to affect imbalances in the relationship between glutamate and γ-aminobutyric acid (GABA), and to reduce inflammation through effects on neuron-glia interactions are common underlying mechanisms of these two treatments. This evidence may explain why clozapine is effective in a range of neuropsychiatric disorders. Future increased investigations into epigenetic and connectomic changes produced by clozapine and ECT should provide valuable information about these two treatments and the disorders they are used to treat.