OBJECTIVETo explore the relationship between the 7th exon G894T mutation of endothelial nitric oxide synthase (eNOS) gene and overweight in patients with essential hypertension.

METHODSTotally, 116 patients with essential hypertension taking no medications and 136 normotensives were selected from a steel workers as study subjects. Polymerase chain reaction and restriction fragment length polymorphism were performed to detect mutation of the 7th exon G894T. Additive model was used to analyze interaction between G894T mutation and overweight on hypertension. Population attributable risk percent (PAR%) for them, etiologic fraction, was applied to their contribution to hypertension.

RESULTSThere was a positive interaction between G894T mutation and overweight on essential hypertension, with an index of interaction of 1.99 and attributable interaction percent of 30.76%. Their pure attributable interaction percent was 36.38%. Multiple logistic regression analysis showed that there still was positive interaction between G894T mutation and overweight on essential hypertension, adjusted for age, sex, smoking and alcohol drinking. Index of their attributable interaction was 2.85, with attributable interaction percent of 39.97%, also adjusted for the above-mentioned factors. Their pure attributable interaction percent was 46.49% and PAR% was estimated as about 15% under certain condition.

CONCLUSIONSInteraction between mutation of the 7th exon G894T of eNOS gene and overweight played an important role in essential hypertension of the studied population. Control of body weight in the population with both G894T mutation and overweight could markedly decrease their risk of hypertension.