Active Rheumatoid Arthritis and Scoliosis: A Mid-Term Cohort Study.

Study Design: Retrospective cohort study.

Objective: To elucidate the factors related to progression of scoliosis in patients with rheumatoid arthritis (RA) using longitudinal cohort data.

Summary Of Background Data: Thirty percent of patients with RA have lumbar scoliosis. However, the effectiveness of current treatment methods in preventing the progression of scoliosis is not well-understood due to a lack of longitudinal studies.

Methods: We enrolled 180 patients with RA who were followed up for over two years, all of whom underwent standing spinal X-rays. These patients were categorized based on their disease activity score-28 with erythrocyte sedimentation rate (DAS28-ESR) into two groups: those in remission (n=76) and those in non-remission (n=104). We evaluated various radiographic measures, including C7 center sacral vertical line (C7-CSVL), pelvic obliquity, major Cobb angle, and curve location.

Results: Fifty-three (29.4%) patients presented progression of scoliosis during a mean follow-up period of 4.8 years. Patients in the non-remission showed larger Cobb angle at baseline and final follow-up, compared to those in remission. The annual progression rate of the curve was also greater in the non-remission group (1.04 degree /year), than in the remission group (0.59 degree /year, P=0.001). There was no difference in the incidence of new vertebral fractures. The presence of a baseline cobb angle of 10 degree or more (OR: 3.14; 95% CI: 1.38-7.13; P=0.006), glucocorticoid use (OR: 2.88; 95% CI: 1.18-7.06; P=0.021), and non-remission at baseline (OR: 2.83; 95% CI: 1.25-6.41; P=0.012) were significant risk factors for progression of scoliosis.

Conclusion: RA disease activity is linked to progression of scoliosis in patients with RA. Patients with RA who present with an initial scoliosis of 10 degrees or greater, require glucocorticoids for treatment and are in non-remission at baseline may be at high risk for scoliosis progression.