Association of Angiotensin Converting Enzyme Gene Insertion / Deletion Polymorphism with Risk of Ischemic Heart Disease in A Population of Smokers in Southern India

Abstract

Background: Ischemic heart disease (IHD) remains a major public health problem nationally and internationally. Smoking is a major risk factor for IHD.The deletion (D) allele of the angiotensin converting enzyme (ACE) gene polymorphism has been associated with hypertension, ischemic stroke and myocardial infarction. The present study was carried out to determine the association of the ACE gene insertion/deletion (I/D) polymorphism in IHD patients with and without smoking. Materials and Methods: One hundred seven male IHD patients admitted consecutively in the Cardiology unit of a Government Hospital and 100 age and sex matched healthy controls were enrolled in this study.The patients were further divided into smokers and nonsmokers. All the subjects were checked for I/D polymorphism of ACE gene, which is mapped to 17q23.3 with OMIM no 106180, by polymerase chain reaction (PCR). The subjects were also investigated for lipid profile and ejection fraction (EF). Results: We found significant difference in the distribution of D allele between patients and controls (p=0.009, OR 1.69, 95% CI 1.139 to 2.517).The significantly lower EF (p<0.001) was suggestive of greater cardiovascular compromise in smokers. The frequency of ID genotype was significantly associated with cases compared to controls (p=0.012, OR 2.054, 95% CI 1.1694-3.624) but was not significantly associated with smokers as compared to nonsmokers. Conclusion: We infer significant association of D allele with IHD. The smokers with ID genotype should be put on prophylactic ACE inhibitor therapy to prevent the morbidity and mortality associated with IHD.

Keywords

• gene polymorphism
• smoking