Background Approximately 30% of individuals with schizophrenia (SZ) are resistant to conventional antipsychotic drug therapy (AP). Of these, one third are also resistant to the second-line treatment, clozapine. Treatment resistance and refractoriness are associated with increased morbidity and disability, making timely detection of these issues critical. Variability in treatment responsiveness is partly genetic, but research has yet to identify variants suitable for personalizing antipsychotic prescriptions. Methods We evaluated potential associations between response to AP and candidate gene variants previously linked to schizophrenia or treatment response. Two groups of patients with SZ were evaluated; one receiving clozapine (n=135) and the other receiving another second-generation AP (n=61). Single-nucleotide polymorphisms (SNPs) in the genes OXT, OXTR, CNR1, DDC, and DRD2 were analyzed. Results Several SNPs were associated with response vs. resistance to AP or clozapine. Conclusions This is the first study of its kind in our admixed Chilean population to address the complete treatment response spectrum. We identified SNPs predictive of treatment-resistant schizophrenia in the genes OXT, CNR1, DDC, and DRD2.
A review about the putative mechanisms of action of electroconvulsive therapy in schizophrenia in human researchElectroconvulsive therapy (ECT) has multiple uses in psychiatry, but its mechanisms of action (MA) in patients with schizophrenia (PS) are poorly understood. We synthesize and discuss the available evidence in this regard. We conducted a search for primary human studies and systematic reviews searching MA of ECT in PS published in PubMed/Medline, SciELO, PsycInfo, and the Cochrane Library, including 24 articles. Genetic findings are scarce and inconsistent. At the molecular level, the dopaminergic and GABAergic role stands out. The increase in brain derived neurotrophic factor (BDNF) after ECT, is a predictor of positive clinical outcomes, while the change in N-acetyl aspartate levels would demonstrate a neuroprotective role for ECT. This intervention would improve inflammatory and oxidative parameters, thereby resulting in a symptomatic improvement. ECT is associated with an increase in functional connectivity in the thalamus, right putamen, prefrontal cortex and left precuneus, structures that play a role in the neural default mode network. A decrease in connectivity between the thalamus and the sensory cortex and an enhanced functional connectivity of the right thalamus to right putamen along with a clinical improvement have been reported after ECT. Moreover a volumetric increase in hippocampus and insula has been reported after ECT. These changes could be associated with the biochemical pathophysiology of schizophrenia. Most of the included studies are observational or quasi-experimental, with small sample sizes. However, they show simultaneous changes at different neurobiological levels, with a pathophysiological and clinical correlation. We propose that the research on ECT should be carried out from neurobiological dimensions, but with a clinical perspective.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.