Association of TNF-α-308(G/A) and-238(G/A) polymorphisms with non-traumatic osteonecrosis of the femoral head risks: a meta-analysis

Purpose The association between TNF-alpha-308(G/A) and -238(G/A) polymorphisms and the susceptibility of non-traumatic osteonecrosis of the femoral head (NONFH) was investigated in many studies with conflicting results. We aimed to conduct a meta-analysis to evaluate the relationship between them comprehensively. Methods Relevant literatures published in PubMed, Web of Science, Embase, Cochrane library databases, China National Knowledge Infrastructure (CNKI), WANFANG Data, and China Science and Technology Journal Database (CSTJ) updated to January 30, 2018, were reviewed by two investigators independently. Odds ratios (ORs) and its 95% confidence intervals (95% CIs) were calculated by a fixed-effect model based on the indistinctive heterogeneity. Results For TNF-alpha-308(G/A) polymorphism, we recruited five studies including 432 NONFH patients and 760 controls and a statistically significant association was identified in Asians in four modes consisting of alleles mode (OR = 0.648, 95% CI 0.475-0.885), homozygote mode (OR = 0.330, 95% CI 0.136-0.802), dominant mode (OR = 0.344, 95% CI 0.143-0.827), and recessive mode (OR = 0.674, 95% CI 0.468-0.971), but no significant association was observed in Caucasians. For TNF-alpha-238(G/A) polymorphism, three eligible studies including 275 cases and 610 controls were evaluated and there was a significant association in alleles mode (OR = 0.270, 95% CI 0.4148-0.490) as well as recessive mode (OR = 0.254, 95% CI 0.138-0.468). Conclusion This meta-analysis shows that TNF-alpha-308(G/A) and -238(G/A) polymorphisms are associated with the susceptibility of NONFH, while the significant association for 308(G/A) is mainly observed in Asians.