Prognostic factors in juvenile rheumatoid arthritis: a case-control study revealing early predictors and outcome after 14.9 years

Abstract

Objective: To describe the physical and psychosocial outcome in patients with juvenile rheumatoid arthritis (JRA), compared with subjects in the general population, and to determine patient characteristics, HLA alleles, and disease variables within the first 6 months of disease onset that predict persistent disease, joint erosions, and physical disability.

Methods: A cohort of 268 (85%) of 316 patients with JRA first admitted to the hospital between 1980 and 1985 were examined after a median of 14.9 years (range 11.7-25.1) of disease duration. Controls matched for age, sex, and geographic region were randomly selected from the general population. Patients' medical records were retrospectively reviewed. Clinical examinations and radiographs of the hips, ankles, and affected joints were obtained. HLA-DRB1 and DPB1 alleles were determined by genotyping and HLA-B27 by serologic testing. Physical and psychosocial health status was assessed using the Short-Form Health Survey (SF-36) and the Health Assessment Questionnaire (HAQ).

Results: At followup, 133 patients with JRA (50%) were in remission, 63 (24%) had developed joint erosions, and 93 (36%) had impaired physical functioning (HAQ > 0.0). Patients had greater disability, more bodily pain, and poorer general health than controls. Comparable levels of education, social function, and mental health were found, but the patients had higher rates of unemployment than controls (19% vs 7%; p < 0.001). Predictors of persistent disease and joint erosions were: young onset age and large numbers of affected joints, long duration of elevated erythrocyte sedimentation rate (ESR), and positive IgM rheumatoid factor (RF) within the first 6 months. Additionally, persistent disease was predicted by the presence of DRB1*08, and joint erosions were predicted by symmetric arthritis and DRB1*08 and HLA-B27 in combination. DRB1*01 was a predictor of joint erosions in the pauciarticular onset type (n = 163). Predictors of physical disability were: female sex, symmetric arthritis, hip joint involvement, long duration of elevated ESR and IgM RF.

Conclusion: Compared with healthy controls, patients with JRA had impaired physical health and lower employment rates after more than 11 years of disease duration. Elevated ESR, extensive and symmetric arthritis, positive IgM RF, DRB1*08, DRB1*01, HLA-B27 and DRB1*08 in combination, early onset, and female sex were early risk factors for an unfavorable outcome.