Prevalência do polimorfismo G894T do gene da óxido nítrico sintase endotelial e sua associação com hipertensão arterial sistêmica: estudo de base populacional em mulheres do Nordeste Brasileiro

Abstract

Background: Hypertension is one of the most prevalent diseases in the world, accounting for millions of deaths each year. The reduction in the concentration of nitric oxide (NO) produced by the catalysis of endothelial nitric oxide synthase (eNOS) is associated with higher blood pressure (BP) levels. This reduction might be because of genetic polymorphisms. This study investigated the prevalence of the eNOS gene G894T polymorphism in women from northeast Brazil and its association with hypertension. Methods: This cross-sectional study included 810 women (aged 20-49 years). Sociodemographic, health, anthropometric, and BP data were collected. Hypertension was defined according to the following criteria: systolic BP≥140 mmHg, diastolic BP≥90 mmHg, the regular use of antihypertensive medication, or some combination therein. Epithelial cells from the cheek mucosa were obtained for DNA extraction. Genotyping was performed via real-time PCR. The measure of association was the prevalence ratio (PR) and its 95% CI as calculated via Poisson regression. Results: The frequencies of the GG, GT, and TT genotypes were 57.1%, 35.7%, and 7.2%, respectively. For each of these genotypes, the prevalence of hypertension in women was 17.9%, 23.6%, and 34.4%, respectively. Relative to the GG genotype, the PRs after adjusting for confounds were 1.24 (95%CI=0.95-1.61, p=0.11) for GT and 1.76 (95%CI=1.16-2.67, p<0.01) for TT. Conclusions: Women with the T allele are more susceptible to hypertension, possibly as a consequence of the lower metabolic production of NO. These findings highlight the need for greater care in the prevention of hypertension among individuals with this genetic polymorphism.