Association of HLA-DR1, HLA-DR13, and HLA-DR16 Polymorphisms with Systemic Lupus Erythematosus: A Meta-Analysis

OBJECTIVES: The principal purpose of this meta-analysis was to assess the association between HLA-DRB1 (HLA-DR1, HLA-DR13, and HLA-DR16) polymorphisms and SLE susceptibility. METHODS: We searched published case-control studies on the association between HLA-DRB1 polymorphisms and SLE susceptibility from PubMed and Web of Science databases. The pooled ORs with 95% CIs were utilized to estimate the strength of association of HLA-DR1, HLA-DR13, and HLA-DR16 polymorphisms and SLE susceptibility by fixed effect models. We also performed sensitivity analysis, trial sequential analysis, Begg's test, and Egg's test in this meta-analysis. RESULTS: A total of 18 studies were included in this meta-analysis. Overall analysis showed that HLA-DR1 and HLA-DR13 polymorphisms were associated with a decreased risk of SLE (OR = 0.76, 95% CI: 0.65-0.90, P < 0.01; OR = 0.58, 95% CI: 0.50-0.68, P < 0.01), and HLA-DR16 polymorphism was associated with an increased risk of SLE (OR = 1.70, 95% CI: 1.24-2.33, P < 0.01). In subgroup analysis of ethnicity, the results were as follows: HLA-DR1 polymorphism in Caucasians (OR = 0.76, 95% CI: 0.58-0.98,P = 0.04) and North Americans (OR = 0.64, 95% CI: 0.42-0.96,P = 0.03); HLA-DR13 polymorphism in Caucasians (OR = 0.62, 95% CI: 0.47-0.82,P < 0.01) and East Asians (OR = 0.44, 95% CI: 0.34-0.57,P < 0.01); and HLA-DR16 polymorphism in East Asians (OR = 2.62, 95% CI: 1.71-4.03,P < 0.01). CONCLUSIONS: This meta-analysis showed that HLA-DR1 and HLA-DR13 are protective factors for SLE, and HLA-DR16 is a risk factor. Due to the limitations of this meta-analysis, the association between HLA-DRB1 polymorphisms and SLE susceptibility needs to be further researched before definitive conclusions are proved.