The current reports on the association between HLA-DPB1 alleles and rheumatoid arthritis (RA) results were controversial. Thus, we conducted a meta-analysis to assess whether DPB1 alleles are associated with increased risk of rheumatoid arthritis.
Systematic searches on PubMed, Embase, Elsevier, CNKI (China National Knowledge Infrastructure), Wanfang data and Cochrane Library prior to July 2017 were performed. The pooled odds ratios (ORs) and 95% confidence interval (95% CI) was used to assess the association between frequencies of DPB1 alleles and RA patients.
Eight studies with 592 cases and 935 controls were included in this meta-analysis. Overall, the pooled ORs showed that frequencies of DPB1*0401 and *0601 were higher in the RA group compared with controls (*0401: OR: 1.586, 95%CI: 1.296-1.941, P<0.001; *0601: OR: 1.921, 95%CI: 1.142-3.229, P=0.014). Whereas, the frequencies of DPB1*0101, *0402 and *0501 were lower in the RA control than the controls (*0101: OR: 0.691, 95%CI: 0.481-0.993, P=0.046; *0402: OR: 0.707, 95%CI: 0.555-0.902, P=0.005; *0501: OR: 0.502, 95%CI: 0.329-0.767, P=0.001). No associations were observed for DPB1*0201, *0202, *0301 and *0901 (*0201: OR: 1.129, 95%CI: 0.882-1.446, P = 0.335; *0202: OR: 0.840, 95%CI: 0.940-1.441, P = 0.527; *0301: OR: 0.769, 95%CI: 0.577-1.026, P = 0.074; *0901: OR: 1.221, 95% CI: 0.541-2.755, P = 0.630).
This meta-analysis demonstrates that high frequency expression of DPB1*0401 and *0601 are significantly associated with susceptibility to RA, it may be a risk factor for occurrence of RA. Low frequency expression of DPB1*0101, *0402 and *0501 may be negatively associated with RA, it may be a protective factor for occurrence of RA.