INFLUENCE OF ANGIOTENSIN-II TYPE-1 RECEPTOR POLYMORPHISM ON AORTIC STIFFNESS IN NEVER-TREATED HYPERTENSIVE PATIENTS

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 contribu tion 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 inc luded in the study. Aortic distensibility was evaluated by measuring c arotid-femoral pulse wave velocity. Age, systolic and diastolic pressu re, and metabolic parameters were similar in the three genotypes. Puls e 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 r atio of total to high-density lipoprotein cholesterol in terms of the development of aortic stiffness. Thus, a positive correlation was obse rved between the ratio of total to high-density lipoprotein cholestero l and pulse wave velocity in AC and CC (r=.42, P<.001) but not AA pati ents. These results suggest that the AT(1) gene is involved in the dev elopment of aortic stiffness in hypertensive patients and could modula te the effects of lipids on large arteries.