Association between interleukin-8 gene -251 A/T polymorphism and the risk of coronary artery disease: A meta-analysis

Background: The association between interleukin-8 (IL-8) gene polymorphism −251 A>T and susceptibility to coronary artery disease (CAD) has been investigated previously; however, results remain controversial. Thus, a meta-analysis was conducted to reassess the effects of this polymorphism on CAD risks. Methods: The PubMed, Cochrane Library, China National Knowledge Infrastructure, and Wanfang databases were searched for relevant studies published up to December, 2018. The pooled odds ratios (OR) were calculated using STATA 13.0 software for allelic (A vs T) as well as homozygote (AA vs TT), heterozygote (AT vs TT), recessive (AA vs AT + TT), and dominant (AA + AT vs TT) genotype models, respectively. Results: Ten case-control studies (3744 cases and 3660 controls) were included. Overall, a significant association of IL-8 gene −251 A > T polymorphism with an increased risk of CAD was only observed in the dominant genotype model (OR = 1.48), but not others. In the subgroup analysis, significantly increased risks were also found for Chinese (OR = 1.64), polymerase chain reaction-restriction fragment length polymorphism genotyping (OR = 1.61), acute coronary syndrome (ACS) type (OR = 1.92 for 3 datasets; OR = 1.88 for 4 datasets), high quality (OR = 1.64), and age/gender matching status (OR = 1.55) under the dominant model. Furthermore, significantly increased risks were also found for ACS type under allelic (OR = 1.32 for 3 datasets; OR = 127 for 4 datasets), homozygote (OR = 1.64 for 3 datasets; OR = 1.50 for 4 datasets), heterozygote (OR = 1.32 for 3 datasets; OR = 1.30 for 4 datasets), and recessive (OR = 1.40 for 3 datasets; OR = 1.28 for 4 datasets) models. Conclusion: This meta-analysis suggests that Chinese patients carrying −251A allele of IL-8 may have an increased risk for the development of CAD, especially ACS.