Angiotensin-converting enzyme and bradykinin gene polymorphisms and cough: A meta-analysis

AIM: To evaluate the association between genetic polymorphisms and angiotensin converting enzyme inhibitor (ACEI)-related cough, and the race-or ethnicityrelated difference in the prevalence of cough attributed to ACEI therapy. METHODS: We conducted a search in PubMed, EMBASE, Cinahl, and the Cochrane Database without language limitation. A database of 11 studies on ACEI-related cough, with detailed information regarding ACE I/D or bradykinin B-2 receptor polymorphisms, was created. Eligible studies were synthesized using meta-analysis methods, including cumulative meta-analysis. A subgroup analysis was also performed using ethnicity. RESULTS: Six studies were included on ACE I/D polymorphism (398 Caucasians, 723 East Asians), and three studies were included on bradykinin B2 receptor polymorphism (300 East Asians). The distribution of ACE genotypes showed significant differences in the entire population (P = 0.004) and in East Asians (P = 0.005) but not in Caucasians (P = 0.23). Allelic frequencies of ACE showed significant differences in East Asians [odds ratio (OR) = 1.49 (1.11-2.02)]. The meta-analysis with a random effects model showed a significant association between ACE allele I/D and ACEI-related cough [random effects (RE) OR = 1.49 (1.11-2.02), P = 0.009] in East Asians, but not in Caucasians [RE OR = 0.90 (0.60-1.35)]. The allelic frequencies of the bradykinin B-2 receptor gene were significantly different [OR = 2.25 (1.42-3.57)]. The distributions of the T/C genotypes of the bradykinin B2 receptor gene were significantly different (chi(2) = 8.366, P = 0.015). The meta-analyses revealed that there was a significant association between the bradykinin B2 receptor allele and ACEI-related cough in East Asians [RE OR = 2.29 (1.42-3.69), P = 0.001]. CONCLUSION: ACE I/D and Bradykinin B-2 receptor polymorphisms contributed to the risk of ACEI-related cough in East Asians, but a negative association between ACE I/D polymorphism and ACEI-related cough was observed in Caucasians. (C) 2011 Baishideng. All rights reserved.