Bone loss in RA may predict radiographic damage

Generalized bone mineral density (BMD) may be used as a predictor of subsequent radiographic damage in African Americans who have recent-onset rheumatoid arthritis (RA). Radiographic damage and reduced generalized BMD in patients who have RA may share a common mechanism.

Zhang and associates examined changes in BMD in 141 patients from the multicenter Consortium for the Longitudinal Evaluation of African Americans with Early RA registry. They measured BMD at the femoral neck or spine and calculated each patient’s T score at baseline. They also obtained hand and wrist films (evaluated using the modified Sharp/van der Heijde score [SHS]).

More patients had osteopenia or osteoporosis in the femoral neck than in the spine (44.9% vs 38.6% of patients). However, persons with generalized bone loss had a higher average SHS and more radiographic progression of RA than those who had normal BMD. After controlling for multiple variables, low BMD in the femoral neck was a more significant predictor of RA progression and was more closely correlated with SHS at 3 years than low BMD in the spine.

The authors noted that their results raise the question of whether bone density is already reduced in patients with early RA compared with the general population.