Association between the ADRA2A 1291 C/G polymorphism and the metabolic syndrome

Background: Studies have found an association between the ADRA2A 1291 C/G polymorphism and antipsychoticinduced weight gain. A possible association with the metabolic syndrome has not been studied. Objectives: To investigate the association between the ADRA2A 1291 C/G polymorphism and the metabolic syndrome. Methods: A cross-sectional design was used to assess the association between ADRA2A 1291 C/G genotype and the metabolic syndrome in patients diagnosed with schizophrenia or related disorders. Patients ≥18 years, were eligible for inclusion. Setting This study included patients from three pooled comparable patient populations from the northern part of the Netherlands. Main outcome measures Primary endpoint was prevalence of the metabolic syndrome. Statistical analysis The association between carriership of the variant 1291 Gallele and prevalence of the metabolic syndrome was investigated with logistic regression. Data were investigated for confounding effects of age, HTR2c-genotype, ethnicity, DSM-IV diagnosis, sex and antipsychotic drugs. Results: 470 patients, mainly male (68%) and Caucasian (94%) were included. There was no significant association between carriership of the variant 1291 G-allele and prevalence of the metabolic syndrome (OR 0.73;95% CI 0.49-1.15). Exploratory analysis showed an association between carriership of the variant 1291 G-allele and a reduced prevalence of the metabolic syndrome in patients not currently using antipsychotics (OR 0.05; 95%CI 0.003-0.97, p 0.048). Conclusions: This study shows that the ADRA2A 1291 C/G polymorphism does not appear to be a strong predictor for long term occurrence of the metabolic syndrome in patients using antipsychotic drugs. The results found in the population not currently using antipsychotics require further investigation.