Association of HLA shared epitope with joint damage progression in rheumatoid arthritis

A nine years prospective study was performed on 82 Spanish rheumatoid arthr itis patients with a disease duration of less than two years at the study e ntry, in order to evaluate the role of HLA markers in the susceptibility an d progression of rheumatoid arthritis. Radiological evaluation of disease s everity was performed at the time of diagnosis and 9 years later. High reso lution HLA-DR typing demonstrated chat the presence of the shared epitope ( SE) was more frequent among patients (61% vs. 31% in controls; P = 0.00003; OR = 3.48). Fourteen patients carried two SE+ HLA-DRB1 alleles (Si +/+); 3 6, one single allele (SE +/-) and 32 were SE negative(SE -/-). HLA-DR4 (par ticularly DRB1*0401 and DRB1*0405) and HLA-DR10 were increased among patien ts. Ar study entry, the frequencies of locally severe (hands and feet) RA w ere more frequent among SE +/+ patients (79%) than among SE +/- (47%) and S E -/- (44%) patients (p = 0.05; RR = 1.80). After 3 years of disease these differences disappeared, where as differences in the extent of the disease arise: 79%, 50% and 32% of SE +/+, SE +/- and SE -/- patients respectively showed large joints involvement (shoulders, elbows, hips and knees) (p = 0. 01; RR = 2.44 for SE+/+ vs. SE -/-; and p = 0.04; RR = 1.81 for SE+ vs. SE- ). These results suggest that the presence of the shared epitope is associa ted with the extent and progression of radiological joint damage in rheumat oid arthritis. Human Immunology 60, 250-254 (1999). (C) American Society fo r Histocompatibility and Immunogenetics, 1999. Published by Elsevier Scienc e Inc.