Association between cyclooxygenase-2 gene polymorphisms and risk of periodontitis: a meta-analysis involving 5653 individuals.

There -765G > C, -1195G > A, and 8473T > C polymorphisms in cyclooxygenase-2 (COX-2) gene polymorphisms and periodontitis risk were investigated based on published studies; however, their results could not give a conclusive result. Hence, we performed this meta-analysis of six published studies with eight case-control studies including these three polymorphisms which searched from PubMed and Web of Science up to October 15th, 2013. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the association between the three polymorphisms of COX-2 and periodontitis risk. The results from 2,580 periodontitis patients and 3,073 healthy controls showed that none of -765G > C, -1195G > A, or 8473T > C polymorphism was not associated with periodontitis susceptibility [Take -765G > C for example: OR = 0.94, 95% CI = (0.57-1.53) for C vs. G; OR = 2.34, 95% CI = (0.72-7.62) for CC vs. GG; OR = 0.68, 95% CI = (0.46-1.01) for CG vs. GG; OR = 0.81, 95% CI = (0.52-1.27) for (CG+GG) vs. GG; OR = 2.57, 95% CI = (0.80-8.29) for CC vs. (GG+CG)]. In subgroup analyses according to the type of periodontitis and ethnicity for -765G > C and -1195G > A, and deviations in Hardy-Weinberg equilibrium for -765G > C, we only observe a boundary association between -1195G > A polymorphism and Asian population. However, due to limitations of this meta-analysis, the results should treat with caution and we suggest the further researches should be carried out to verify our results.