The influence of HLA-DRB1 alleles and rheumatoid factor on disease outcome in an inception cohort of patients with early inflammatory arthritis.
OBJECTIVE
There are conflicting data concerning the role of HLA-DRB1 alleles in disease outcome in early rheumatoid arthritis. The exact role of these alleles in short-term outcome is determined in this large, prospective, population-based study.


METHODS
We recruited 532 patients with inflammatory polyarthritis from the Norfolk Arthritis Register and typed their sera for HLA-DRB1 alleles using polymerase chain reaction-based methods. Disease outcome was assessed at 2 years in terms of persistent joint inflammation, functional disability, and radiologic erosions. Results are expressed as risk ratios (RR) with 95% confidence intervals (95% CI).


RESULTS
There was no influence of HLA-DRB1 alleles, in any combination, on the likelihood of disease persistence, and only a modest effect on functional disability (Health Assessment Questionnaire score > or = 1). The most obvious effect was on the development of erosions (RR 1.9, 95% CI 1.4-2.6 for those who carried at least 1 DRB1 shared epitope [SE] allele), with slightly greater effects for those who were homozygous for SE-bearing alleles (RR 2.5, 95% CI 1.8-3.6). This effect of HLA-DRB1 was restricted to patients whose sera were negative for rheumatoid factor. Among patients with erosions, HLA-DRB1 had no influence on the severity of radiologic damage (defined as the number of eroded joints, or total Larsen score).


CONCLUSIONS
These data do not support routine HLA-DRB1 screening of patients with early arthritis to identify those at risk for subsequent severe disease.
Harrison
B
B
University of Manchester, UK.
Thomson
W
W
Symmons
D
D
Ollier
B
B
Wiles
N
N
Payton
T
T
Barrett
E
E
Silman
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000235:genetics / Q000276:immunology* / Q000503:physiopathology; D015331:Cohort Studies; D005260:Female; D006684:HLA-DR Antigens / Q000235:genetics* / Q000276:immunology; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains