Levels of the macrophage migration inhibitory factor and polymorphisms in systemic lupus erythematosus: a meta-analysis

Introduction: Several published results have established variations in respect to plasma/serum macrophage migration inhibitory factor (MIF) levels and gene polymorphisms with systemic lupus erythematosus (SLE). This study gave a more concise estimation on the MIF levels for SLE patients and established the association between MIF polymorphisms and SLE. Material and methods: All articles were searched from PubMed, Embase, Web of Science, Wan-Fang, Chinese Biological Medical Literature, and China National Knowledge Infrastructure up to 6th October 2017, with no language restriction. Pooled standard mean difference with 95% confidence interval was evaluated using random effect model. Thirteen articles were used for this meta-analysis, with 620 SLE patients and 779 healthy controls assessed for MIF levels, and 2,159 SLE patients and 2,574 healthy controls considered for MIF-173 C/G and MIF-794 CATT polymorphisms. Results: There was a significant higher MIF levels in SLE patients than in healthy controls (p = 0.004). The subgroup analysis showed Asians and ages < 30 had higher MIF levels in SLE patients than in healthy controls. It was evident that patients with systemic lupus erythematosus diseases activity index scores < 8 and >= 8, and disease duration for both year < 5 and >= 5 of SLE had higher MIF levels when compared to healthy controls. We found a significant association between SLE and MIF-173 C/G, but not MIF-794 CATT. Conclusions: This study provided evidence of significant higher MIF levels in SLE patients and supported the association of MIF-173 C/G and SLE. However, we were not able to establish an association between MIF-794 CATT and SLE.