Background The DD genotype of the angiotensin-converting enzyme (ACE) gene has been proposed as an independent risk factor for cardiovascular diseases. To the present day studies performed in different populations have displayed contradictory results. The aim of our case-control study was to assess the risk of CHD, myocardial infarction and arterial hypertension associated with the insertion/deletion ACE gene polymorphism (I/D ACE) among subjects below 50 years of age.
Methods We compared 99 consecutive patients with CHD confirmed by elective coronarography (mean age 44 ± 4 years, 95 males and 4 females, 76% survived MI, 35% were hypertensive) with 109 controls (negative history of CHD and normal ecg) matched for age and sex (mean age 44 ± 5 years, 100 males, 9 females; 42% were hypertensive). In addition the measurement of standard risk factors was carried out. The polymerase chain reaction and agarose gel electrophoresis were used to determine the ACE I/D genotype.
Results There was no significant difference in the genotype distribution between subjects with CHD (DD 36%, ID 42%, II 22%) and controls (DD 30%, ID 54%, II 16%) p = 0.35. Both study populations were in Hardy-Weinberg equilibrium. In CHD subjects with positive MI history the genotype distribution (DD 42%, ID 38%, II 20%) was not significantly different from controls either p = 0.11. DD genotype frequency was not signifficantly smaller in hypertensive CHD patients in comparison to hypertensive controls (24% vs 30%, p = 0.54). There was no significant difference in DD genotype frequency between normotensive CHD patients and normotensive controls (45% vs 30%, p = 0.08). The deletion genotype was significantly less frequent among hypertensive CHD subjects in comparison to normotensive CHD subjects (24% vs 45%, p < 0.05). In multiple vesel CHD disease (n = 66) DD genotype was observed with similar frequency as in controls (36% vs 30%, p = 0.3). Distribution of the common atherosclerosis risk factors such as: age, BMI, plasma cholesterol and triglicerydes, diabetes, smoking habits was independent from I/D ACE polymorphism in both studied groups.
Conclusion The DD genotype of ACE gene seems not to be associated with coronary heart disease or arterial hypertension among subjects below 50 years of age.