Radiographic Severity of Rheumatoid Arthritis in African Americans: Results From a Multicenter Observational Study

Abstract

Objective. To describe radiographic changes in African Americans with rheumatoid arthritis (RA) from the Consortium for the Longitudinal Evaluations of African Americans with Early Rheumatoid Arthritis (CLEAR) Registry, a multicenter observational study.

Methods. Self-declared African American patients were enrolled in CLEAR I, a longitudinal cohort of early RA (disease duration of <2 years) from 2000 to 2005, or in CLEAR II, a cross-sectional cohort (any disease duration) from 2006 to the present. Demographic and clinical data were obtained, and sets of hand/wrist and foot radiographs were scored using the modified Sharp/van der Heijde scoring system.

Results. A total of 357 and 418 patients were enrolled in CLEAR I and CLEAR II, respectively. We report here an interim analysis of radiographic severity in these patients. For the CLEAR I cohort, 294 patients had a mean radiographic score of 2.89 at the baseline visit; 32.0% showed either erosions (25.9%) or joint space narrowing (JSN; 19.4%). At the 36-month visit, the mean score was 5.65; 44.2% had erosions, 41.5% had JSN, and 54.4% had either. Among those patients without radiographic damage at baseline, 18.9% had progressed at the 36-month visit, compared with 57.1% of those with baseline damage (P < 0.0001). For the CLEAR II cohort, of 167 patients with RA of any duration, 65.3% exhibited joint erosions, 65.3% exhibited JSN, and 74.8% exhibited either. The mean radiographic score was 33.42.

Conclusion. To our knowledge, this is the largest radiographic study of African American RA patients. Damage occurs early in the disease and is associated with radiographic progression at 3 years of disease duration. The CLEAR Registry will provide a valuable resource for future analyses of genetic, clinical, and environmental factors associated with radiographic severity of RA in African Americans.