The association of eNOS G894T polymorphism with metabolic syndrome and erectile dysfunction

Accumulated evidences have outlined the potential relation between insulin resistance and endothelial dysfunction. The impaired ability of endothelium to synthesize or release nitric oxide may provide a common pathophysiological mechanism in the development of metabolic syndrome (MtS) and erectile dysfunction (ED).

The aim of this article was to investigate the genetic susceptibility of endothelial nitric oxide synthase (eNOS) G894T polymorphism underlying the development of both disorders.

A total of 590 subjects with a mean (standard deviation) age of 55.3 years (4.1) were enrolled during a free health screening. Complete clinical data and questionnaires were taken for all subjects. Multivariate logistic regression analysis was used to determine the independent predictors of MtS and ED. The eNOS G894T polymorphism was determined using a polymerase chain reaction-restriction fragment length polymorphism method.

The definition of MtS was according to the modified criteria developed by the Bureau of Health Promotion in Taiwan. Patients with ED were defined as those having a five-item International Index of Erectile Function (IIEF-5) <21.

Our results showed that the eNOS 894T allele carriers had significantly higher prevalence of MtS and ED (odds ratio [OR]=1.64, 95% confidence interval [CI]=1.05∼2.56, P=0.02 and OR=1.76, 95% CI=1.11∼2.80, P=0.01, respectively) after adjustment for each other and age. Also the T allele carriers had significantly lower IIEF-5 score and more MtS components than G allele carriers (P<0.01 and P<0.01, respectively), which were significantly associated with an increment of the T allele number (P<0.05).

The eNOS 894T allele carriers are at greater risk for both MtS and ED, suggesting that eNOS G894T gene polymorphism might play an implication as a common genetic susceptibility factor to develop both disorders.