Objective: Our aim was to determine areal bone mineral density (BMD(a)) and disease-related factors linked with BMD(a) in adults with a history of juvenile idiopathic arthritis (JIA).
Methods: Men and women with a history of JIA attending a young adult rheumatology clinic in Newcastle, UK, underwent dual energy x-ray absorptiometry (DEXA) of the lumbar spine and total hip. Information was obtained about disease duration and subtype, previous treatment including corticosteroid and methotrexate therapy, and large-joint replacement. Subjects completed the modified Health Assessment Questionnaire (HAQ). Blood was taken for assessment of C-reactive protein, erythrocyte sedimentation rate, and rheumatoid factor (RF).
Results: Seventy-one women and 16 men, mean age 28.7 and 31.4 years, and mean disease duration 20.6 and 24.0 years, respectively, were studied. Mean BMD(a) was 0.982 (Z-score = -0.328; 95% CI -0.657, 0.001) and 1.028 g/cm(2) (Z-score = -0.251; 95% CI -1.266, 0.764) in women and men, respectively, at the spine and 0.817 (Z-score = -0.542; 95% CI -0.975, -0.109) and 0.857 g/cm(2) (Z-score = -0.176; 95% CI -2.323, 1.971) at the hip. After adjusting for age and sex, increasing HAQ score was associated with both lower spine BMD(a) and hip BMD(a). Compared with patients with oligoarticular disease, those with enthesitis-related arthritis had higher BMD(a) at the spine, while those with extended oligoarticular and polyarticular RF-negative disease had lower hip BMD(a). Oral corticosteroids and the presence of a large-joint replacement were associated with lower BMD(a) at both the spine and hip.
Conclusion: There was a trend toward low BMD(a) in women with a history of JIA. These patients may be at risk of the complications of osteoporosis including fragility fractures and should be considered for targeted preventive measures.