Association between angiotensin-converting enzyme insertion/deletion polymorphisms and the risk of heart disease: an updated meta-analysis

Insertion/deletion (I/D) polymorphisms of the gene encoding angiotensin converting enzyme (ACE) are a controversial risk factor for heart diseases (HDs). ACE I/D polymorphism has been reported to be associated with various cardiovascular diseases. However, some studies have presented conflicting results. In this study, we aim to explore the association between ACE I/D polymorphisms and the risk of coronary HD (CHD), coronary artery disease (CAD), and myocardial infarction (MI). A meta-analysis was conducted, which included 12,533 cases and 20,726 controls from 75 case-control studies. We performed overall analysis on the entire dataset and found that the D allele of ACE was significantly associated with increased risk of HDs in three different comparison models (dominant, recessive, and homozygote). We also performed analyses on subgroups based on ethnicity as well as disease type. Our results showed that the D allele of ACE was significantly associated with an increased risk of HDs in the Asian and European groups but not in the American group. In addition, in all three subgroups (CHD, CAD, and MI), the D allele of ACE was found to be significantly associated with increased risk of disease. Begg's funnel plots were generated to evaluate publication biases, but no obvious publication bias was found in the studies included in our meta-analysis. In conclusion, our meta-analysis demonstrated that the D allele of ACE was significantly associated with an increased risk of HDs.