Influence of Angiotensin II Type 1 Receptor Polymorphism on Aortic Stiffness in Never-Treated Hypertensive Patients

Abstract
Abstract Several clinical and experimental studies have suggested a significant role of angiotensin II in the development of alterations of small and large arteries. The present study was designed to assess the contribution of polymorphism (corresponding to an A 1166 →C transversion) of the angiotensin II type 1 receptor (AT 1 ) gene to aortic stiffness. One hundred thirty-four never-treated hypertensive patients were included in the study. Aortic distensibility was evaluated by measuring carotid-femoral pulse wave velocity. Age, systolic and diastolic pressure, and metabolic parameters were similar in the three genotypes. Pulse wave velocity was 11.4±2.5 m/s in AT 1 AA homozygotes, 12.5±3.2 m/s in AC heterozygotes, and 14.7±4.0 m/s in CC homozygotes ( P =.003, P <.001 after adjustment for age, blood pressure, and body mass index). Moreover, an interaction was found between AT 1 genotype and the ratio of total to high-density lipoprotein cholesterol in terms of the development of aortic stiffness. Thus, a positive correlation was observed between the ratio of total to high-density lipoprotein cholesterol and pulse wave velocity in AC and CC ( r =.42, P <.001) but not AA patients. These results suggest that the AT 1 gene is involved in the development of aortic stiffness in hypertensive patients and could modulate the effects of lipids on large arteries.