Insertion/deletion polymorphism of the angiotensin-converting enryme gene in elderly patients with arterial hypertension and coronary heart disease

Abstract

Background It has been suggested that the insertion/deletion polymorphism (I/D) of the ACE gene is an independent risk factor for myocardial infarction (MI) and may be associated with pathogenesis of hypertension complications. It is not known however whether the correlation applies to all age grups. The objective of our study was therefore to examine the relationship between the I/D ACE polymorphism and severity of coronary atherosclerosis and MI history and hypertension, respectively, in elderly patients with CHD.
Methods The study was performed in 111 patients (73 males and 38 females) with CHD confirmed by coronary angiography, all were older than 65 years (mean age 69 4 years). 54% of subjects were hypertensive and 50% survived myocardial infarction. The polymerase chain reaction and agarose gel electrophoresis were used to determine the ACE I/D genotype.
Results The observed ACE genotype frequencies in our study group were 28% for DD, 54% for ID, 18% for II and were in Hardy-Weinberg equilibrium. There was no significant difference in the ACE genotype distribution between subjects with MI in history (DD - 29%, ID - 61%, II - 10%) and patients without MI (DD - 27%, ID - 49%, II - 24%, p=0.84). The DD genotype frequency was not significantly higher in hypertensive subjects ( DD - 36%, ID 45%, II - 19%) in comparison to normotensive patients (DD - 21%, ID - 60%, II - 19%, p = 0.13). In addition there was no association of the I/D polymorphism and the number of affected coronary arteries as determined by angiography. Segregation of the ACE genotypes was independent of common risk factors such as: age, body mass index, plasma cholesterol and triglicerydes, diabetes and smoking habits.
Conclusions The DD genotype of the ACE gene is not associated with angiographically proven coronary heart disease, myocardial infarction or hypertension status in older age group.