Erosion-free rheumatoid arthritis: clinical and conceptional implications-a BARFOT study.

One-quarter of the patients was erosion-free during eight years in this early RA cohort. Erosion-free patients had a less severe disease course as to disease activity and were more often seronegative compared with those with erosive disease. The results suggest that non-erosive RA represents a milder form of RA.