Decrease over time in the incidence of systemic rheumatoid vasculitis: Comment on the article by Turesson et al
Article first published online: 5 MAY 2005
Copyright © 2005 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 52, Issue 5, pages 1620–1621, May 2005
How to Cite
Watts, R. A., Lane, S. E. and Scott, D. G. I. (2005), Decrease over time in the incidence of systemic rheumatoid vasculitis: Comment on the article by Turesson et al. Arthritis & Rheumatism, 52: 1620–1621. doi: 10.1002/art.21047
- Issue published online: 5 MAY 2005
- Article first published online: 5 MAY 2005
To the Editor:
We read with interest the recent report by Turesson et al on the incidence of extraarticular manifestations of rheumatoid arthritis (RA) in Olmsted County, Minnesota (1). In contrast to our study in Norfolk, UK, which showed a decline in the incidence of systemic rheumatoid vasculitis over 15 years (2), those authors did not observe such a decline. There are several possible explanations for the different study results. The decrease in incidence of systemic rheumatoid vasculitis in our study only occurred after the mid-1990s (Figure 1), whereas their report does not include any data from after 1994. There were differences in case identification between the 2 studies because our study was hospital based whereas Turesson et al based their study in the community. However, it is likely that patients with severe extraarticular disease will present for hospital-based care at some stage as Turesson and colleagues acknowledge in their conclusion. Our study was based on the date of onset of vasculitis and not on presentation to the hospital or diagnosis of RA. Our methods were also likely to result in identification of a higher incidence of vasculitis compared with their study because we included all patients, regardless of the date of diagnosis or duration of followup. It is worth noting that over a 15-year period, we have not observed a change in the incidence of primary systemic vasculitis (Figure 1). This suggests that the decrease of systemic rheumatoid vasculitis observed in our study is a genuine reduction (3).
Richard A. Watts DM*, Suzanne E. Lane MD*, David G. I. Scott MD, * Ipswich Hospital, Suffolk, UK, Norfolk and Norwich University Hospital, Norfolk, UK.