THE COMBINED EFFECT OF CYP2D6 AND DRD2 Taq1A POLYMORPHISMS ON THE ANTIPSYCHOTICS DAILY DOSES AND HOSPITAL STAY DURATION IN SCHIZOPHRENIA INPATIENTS (OBSERVATIONAL NATURALISTIC STUDY)

Background: To assess the correlation between the antipsychotics (AP) mean daily doses, hospital stay duration and CYP2D6, DRD2 polymorphisms in naturalistic study. Subjects and methods: CYP2D6 polymorphisms *3, *4, *5, *6, *1XN and DRD2/ANKK1 Taq1A polymorphisms were genotyped in a cohort of 226 Caucasian schizophrenic inpatients. AP daily doses, hospital stay duration and AP treatment duration were taken from medical records. To compare mean daily doses of AP among CYP2D6 PMs, EMs, UMs and DRD2/ANKK1 Taq1A carriers the actual AP doses were converted to chlorpromazine (CPZ) equivalents and DDD (defined daily dose). Results: Significant correlation (p=0.004) between CYP2D6 metabolic activity and AP mean daily doses was observed only among DRD2/ANKK1 Taq1A polymorphic allele carriers: 250.53 (95%CI: 154.90-346.17), 473.82 (95%CI: 426.99-520.64) 602.77 (95%CI: 469.65-735.88) CPZ equivalents in PMs, EMs and UMs, consequently. PMs with DRD2/ANKK1 Taq1A CT genotype received significantly lower doses of AP comparing to CC genotype (p=0.02). Mean hospital stay duration of PMs+UMs was significantly higher comparing to EMs (66.4 days (95% CI: 56.9-75.8) vs 50.2 days (95%CI: 45.5-54.7); p=0.047). Conclusions: In a cohort of schizophrenia inpatients CYP2D6 metabolic activity affects mean AP daily dose only in the presence of DRD2 Taq1A polymorphic allele. CYP2D6 metabolic activity correlates independently from DRD2 Taq1A polymorphism with hospital stay duration. Subpopulation of schizophrenia inpatients with altered CYP2D6 activity (PMs and UMs) carriers of Taq1A polymorphisms needs special attention of clinicians in aligning of AP treatment

Genetic Predisposition to Schizophrenia and Depressive Disorder Comorbidity

Background: Patients with schizophrenia have an increased risk of depressive disorders compared to the general population. The comorbidity between schizophrenia and depression suggests a potential coincidence of the pathophysiology and/or genetic predictors of these mental disorders. The aim of this study was to review the potential genetic predictors of schizophrenia and depression comorbidity. Materials and Methods: We carried out research and analysis of publications in the databases PubMed, Springer, Wiley Online Library, Taylor & Francis Online, Science Direct, and eLIBRARY.RU using keywords and their combinations. The search depth was the last 10 years (2010–2020). Full-text original articles, reviews, meta-analyses, and clinical observations were analyzed. A total of 459 articles were found, of which 45 articles corresponding to the purpose of this study were analyzed in this topic review. Results: Overlap in the symptoms and genetic predictors between these disorders suggests that a common etiological mechanism may underlie the presentation of comorbid depression in schizophrenia. The molecular mechanisms linking schizophrenia and depression are polygenic. The most studied candidate genes are GRIN1, GPM6A, SEPTIN4, TPH1, TPH2, CACNA1C, CACNB2, and BCL9. Conclusion: Planning and conducting genome-wide and associative genetic studies of the comorbid conditions under consideration in psychiatry is important for the development of biological and clinical predictors and a personalized therapy strategy for schizophrenia. However, it should be recognized that the problems of predictive and personalized psychiatry in the diagnosis and treatment of schizophrenia and comorbid disorders are far from being resolved

Association of a Single-Nucleotide Variant rs11100494 of the NPY5R Gene with Antipsychotic-Induced Metabolic Disorders

Background: The usage of antipsychotics (APs) is the most robust and scientifically based approach in the treatment of schizophrenia spectrum disorders (SSDs). The efficiency of APs is based on a range of target receptors of the central nervous system (CNS): serotoninergic, dopaminergic, adrenergic, histaminergic and cholinergic. Metabolic disorders are the most severe adverse drug reactions (ADRs) and lead to cardiovascular diseases with a high rate of mortality in patients with SSDs. Neuropeptide Y receptor Y5 (NPY5R) is known in the chain of interaction to target receptors for APs, agouti-related peptide receptors and proopiomelanocortin receptors. We studied the association of the single-nucleotide variants (SNVs) rs11100494 and rs6837793 of the NPY5R gene, and rs16147, rs5573, rs5574 of the NPY gene, with metabolic disorders in Russian patients with SSDs. Methods: We examined 99 patients with SSDs (mean age—24.56 years old). The mean duration of APs monotherapy was 8 weeks. The biochemical blood test included levels of glucose, cholesterol, lipoproteins, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein and albumin. Anthropometry included weight, height, waist circumference and hip circumference. We used real-time PCR to study the carriage of major and minor alleles of the SNV rs11100494 (1164C>A) of the NPY5R gene (chromosome localization—4q32.2). Group 1 comprised 25 patients with SSDs taking APs with a change in body weight of more than 6% since the start of APs therapy. Group 2 comprised 74 patients with SSDs taking APs with a change in body weight of less than 6% since the start of APs therapy. Results: We show the significance of genetic risk factors (carriage of major allele C of SNV rs11100494 of the NPY5R gene) for the development of AP-induced weight gain in Russian patients with SSDs. The allele C predisposes to AP-induced weight gain (OR = 33.48 [95% CI: 12.62; 88.82], p-value < 0.001). Additionally, the results of our study demonstrate that first-generation APs (FGAs) are more likely to cause an increase in serum transaminase levels but are less likely to increase body weight. Second-generation APs (SGAs) are more likely to cause weight gain and changes in serum glucose levels. Conclusion: Our study shows the predictive role of the allele C of SNV rs11100494 of the NPY5R gene in the development of AP-induced weight gain. However, we did not find a significant association between biochemical markers and this SNV in Russian patients with SSDs