HLA-DRB1 shared epitope allele polymorphisms and rheumatoid arthritis: a systemic review and meta-analysis

A meta-analysis was preformed to determine which HLA-DRB1 alleles are associated with increased risk of rheumatoid arthritis (RA) in Asian patients.

Medline, PubMed, Central, EMBASE, Cochrane, and Google Scholar databases were searched until November 3, 2015 using the following keywords: rheumatoid arthritis; RA, HLA-DRB1; severity; treatment; and, prognosis. Randomized-controlled-trials, prospective, retrospective, cohort and case-controlled studies that examined the HLA-DRB1 allelic association with RA in Asians were included. The frequencies of allelic types and the shared epitope (SE) were compared between patients with or without RA.

A total of 331 articles were identified after duplicates removed, and 40 studies, with 5470 RA patients and 5837 control patients, were included in the analysis. Pooled odds ratios (ORs) revealed the frequencies of HLA-DRB1*04 and *10 were higher in the RA group, and the frequency of *14 was lower in the RA group as compared to controls (*04: OR = 3.35, 95% CI: 2.28-3.99, p < .001; *10: OR = 2.08, 95% CI: 1.55-2.78, p < .001; *14: OR = 0.70, 95% CI: 0.54-0.90, p = .006). No associations were noted for *01 and *09. Pooled ORs revealed associations of *0101 (OR = 1.58), *0401 (OR = 2.17), *0404 (OR = 1.91), *0405 (OR = 3.73), *0410 (OR = 2.24), *1001 (OR = 1.78) and SE positive (OR = 2.38) with RA. HLA-DRB1 *14 subtypes did not show associations with RA.

HLA-DRB1 allelic variations are associated with RA in Asian patients.