Association between angiotensin-converting enzyme gene polymorphism and carotid atherosclerosis in elderly essential hypertension

Objective To investigate the relationship between insertion/deletion(I/D) polymorphism of angiotensin converting enzyme(ACE) gene and carotid atherosclerosis in elderly essential hypertension. Methods An I/D polymorphism in ACE gene was detected by polymerase chain reaction(PCR) in 126 cases of elderly essential hypertension(hypertension group) and 72 cases of healthy elders(control group).Based on the I/D polymorphism,the hypertension group was divided into three subgroups: DD type group(n=34),Ⅱ type group(n=42), and ID type group (n=50).The mean intimal-medial thickness (MIMT),Crouse score and plaques of carotid were measured by high-resolution ultrasonography for each of subgroups. Results No significant differences were observed between the hypertension group and control group in frequency of ACE genotype and alleles.Among three subgroups,DD genotype group had higher MIMT,more carotid plaques and higher Crouse score than those in Ⅱ genotype [( 0.95± 0.15) mm vs ( 0.85± 0.11) mm, 82.35% vs 57.14%,all P 0.05,and ( 7.13± 6.64) mm vs ( 2.63± 2.40) mm,P 0.01].Conclusion No association was indicated between ACE gene polymorphism and elderly essential hypertension.DD genotype may be a genetic marker responsible for the genetic predisposition to carotid atherosclerosis and vascular damage in essential hypertension.