Increased Frequency of Angiotensin-Converting Enzyme D Allele in Asian Patients With Chronic Obstructive Pulmonary Disease: An Updated Meta-Analysis.

At present, the angiotensin-converting enzyme (ACE) I/D polymorphism was considered to be associated to the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the association between it and the risk of COPD in different ethnic groups is still unclear. The purpose of this study is to conduct an updated meta-analysis of the association between them; collect literatures published before 10 February 2023 by searching PubMed, Embase, MEDLINE, CBM, CNKI, Wanfang, and VIP Chinese scientific databases; and display the analysis results by drawing forest plots. At the same time, publication bias, sensitivity analysis, and trial sequential analysis (TSA) were performed to evaluate the stability and reliability of the results. In the overall population, the result of the DD versus II model showed the association with the risk of COPD ([OR] = 1.30, 95% CI [1.08, 1.56]), and there were no associations in other genetic models (p > 0.05). In Caucasians, the results of all genetic models showed no associations (p > 0.05). In Asians, the results of D versus I, DD versus II, and DD versus II + ID models showed the associations with the risk of COPD (D vs. I: [OR] = 1.48, 95% CI [1.14, 1.93]; DD vs. II: [OR] = 2.04, 95% CI [1.53, 2.72]; DD vs. II + ID: [OR] = 2.19, 95% CI [1.45, 3.29]), while the results of ID versus II and DD + ID versus II models showed no associations (p > 0.05). Therefore, the D allele and "DD" genotype variation of the ACE I/D gene polymorphism are associated with susceptibility to COPD in Asians but not in Caucasians.