title: HTR2C gene polymorphisms and the metabolic syndrome in patients with schizophrenia: a replication study.
abstract: In a previous study, we found an association between 5-hydroxytryptamine (serotonin) receptor 2C (HTR2C) polymorphisms and the occurrence of the metabolic syndrome in patients using antipsychotics. In the current study, we set out to replicate our findings in another sample of patients and to explore in a pooled analysis of both samples the influence of the effect of individual antipsychotics. Data for this cross-sectional study came from 2 different samples, the original sample (n = 112) and the replication sample (n = 164). Primary end point was the prevalence of the metabolic syndrome as classified by a modified version of the National Cholesterol Education Program's Adult Treatment Panel III. Primary determinants were polymorphisms in the promoter region of the HTR2C gene [HTR2C:c.1-142948(GT)n, rs3813929 (-759 C/T), and rs518147 (-697 G/C)] and an intragenic polymorphism (rs1414334:C>G). The variants of HTR2C:c.1-142948(GT)n (odds ratio [OR], 1.69; 95% confidence interval [CI], 0.75-3.81) and rs1414334 (OR, 2.35; 95% CI, 0.96-5.77) were not significantly associated with the metabolic syndrome in the replication sample but did show significance in the pooled analysis (OR, 2.09; 95% CI, 1.12-3.91; and OR, 2.35; 95% CI, 1.19-4.62, respectively). The variant rs1414334 C allele was specifically associated with the metabolic syndrome in patients using clozapine (OR, 9.20; 95% CI, 1.95-43.45) or risperidone (OR, 5.35; 95% CI, 1.26-22.83). This study extends previous findings to a larger sample of patients and implicates specific antipsychotic drugs. The increased risk for the metabolic syndrome is particularly strong in carriers of the rs1414334 C allele using clozapine or risperidone.
authors.affiliation: Division of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands.
authors.forename: Hans
authors.initials: H
authors.lastname: Mulder
authors.forename: Dan
authors.initials: D
authors.lastname: Cohen
authors.forename: Hans
authors.initials: H
authors.lastname: Scheffer
authors.forename: Christine
authors.initials: C
authors.lastname: Gispen-de Wied
authors.forename: Johan
authors.initials: J
authors.lastname: Arends
authors.forename: Frederik W
authors.initials: FW
authors.lastname: Wilmink
authors.forename: Barbara
authors.initials: B
authors.lastname: Franke
authors.forename: Antoine C G
authors.initials: AC
authors.lastname: Egberts
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use; D003024:Clozapine / Q000009:adverse effects / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000235:genetics*; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D044405:Receptor, Serotonin, 5-HT2C / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012306:Risk; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use; D012559:Schizophrenia / Q000150:complications / Q000188:drug therapy / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D044405:Receptor, Serotonin, 5-HT2C; D003024:Clozapine; D018967:Risperidone