Predisposition of Inflammatory Bowel Disease Is Influenced by IL-8, IL-10, and IL-18 Polymorphisms: A Meta-Analysis

Background: Whether interleukin (IL)-8, IL-10, and IL-18 polymorphisms influence predisposition of inflammatory bowel disease (IBD) remains uncertain. Objectives: The authors conducted a meta-analysis to explore relationships between IL-8, IL-10, or IL-18 polymorphisms and predisposition of IBD by merging the results of eligible literatures. Methods: A thorough literature search in MEDLINE, Embase, Wanfang, VIP, and CNKI was conducted by the authors to identify eligible literatures, and 33 literatures were finally selected for merged analyses. Results: We found that genotypic frequencies of IL-8 rs4073, IL-10 rs1800871, IL-10 rs1800872, and IL-10 rs1800896 polymorphisms among cases with IBD and population-based controls differed significantly. Moreover, we found that genotypic frequencies of IL-8 rs4073, IL-10 rs1800871, and IL-18 rs1946518 polymorphisms among cases with IBD and population-based controls of Asian origin differed significantly, whereas genotypic frequency of IL-10 rs1800896 polymorphism among cases with IBD and population-based controls of Caucasian origin also differed significantly. Furthermore, genotypic frequency of IL-18 rs187238 polymorphism among cases with Crohn’s disease (CD) and population-based controls also differed significantly. Conclusions: The present meta-analysis shows that IL-8 rs4073, IL-10 rs1800871, IL-10 rs1800872, IL-10 rs1800896, and IL-18 rs1946518 polymorphisms may influence predisposition of IBD. Furthermore, IL-18 rs187238 polymorphism may influence predisposition of CD, but not predisposition of ulcerative colitis.