Postoperative nausea and vomiting: The role of the dopamine D2 receptor TaqIA polymorphism.

Abstract

The risk of developing postoperative nausea and vomiting (PONV), apart from conventional risk factors, probably includes a genetic background. We examined the association of the DRD2 TaqIA polymorphism with PONV in a high-risk cohort of patients. A prospective, double-blind observational trial. Single-centre primary care in Western Germany. A total of 306 patients undergoing elective strabismus surgery under anaesthesia with etomidate/alfentanil/mivacurium (induction) and sevoflurane in air (maintenance). Nausea as well as retching/vomiting was recorded for 24 h postoperatively. The DRD2 TaqIA polymorphism (rs1800497) was genotyped using a Taqman assay and the relationship between DRD2 TaqIA polymorphism and PONV was examined by univariate and multivariate analysis. Regarding known risk factors for developing PONV, no patient with the A1A1 genotype (n = 15) had a history of PONV, while A1A2 carriers (n = 115) and A2A2 carriers (n = 176) had a history of PONV in 22.6 and 10.8% of patients, respectively (P = 0.005). Overall, the incidence of nausea was 40.1% and the incidence of vomiting/retching was 32.7%. Univariate analysis showed that postoperative nausea was not associated with TaqIA genotypes, but the incidence of retching/vomiting in A1A2 and A2A2 genotypes was more than 34% compared with zero in A1A1 genotypes (P = 0.022). Age, sex, smoking status and a history of PONV were independent predictors for nausea as well as for retching/vomiting, as expected, while DRD2 TaqIA polymorphism showed no independent significant impact. In a white cohort, the TaqIA A2 allele is significantly associated with a history of PONV, which may explain the increased incidence of PONV but has no further independent influence. German registry of clinical trials identifier: DRKS00005681.