The results of this study imply the potential role of CYP2D6 genotyping in personalizing risperidone therapy in patients with schizophrenia to reduce the incidence of adverse extrapyramidal symptoms.
The aim of the presentation was to evaluate the impact of CYP2D6 genotype on psychopathological and extrapyramidal symptoms in a group of Slovenian outpatients with schizophrenia or schizoaffective disorder in stable remission, who were receiving long-term maintenance therapy.
We found a non-significant over-representation of poor metaboliser genotypes among cases, but a significant association between the mutant homozygous genotype for CYP2D6*4 (odds ratio (OR) 4.1, 95% confidence interval (CI) 1.01-16, permutated P value 0.01) and the heterozygous genotype for CYP2D6*6 (OR 5.4, 95% CI 1.13-18, permutated P value 0.003) and the risk of suffering EPS.3.
Furthermore, there were no differences in the risperidone/9-hydroxyrisperidone ratio, clinical improvements and extrapyramidal symptoms among cyp2D6 genotypes.