Observational Data to Study Medication Outcomes in Systemic Sclerosis: Table 1.

Abstract

To the Editor: Systemic sclerosis (SSc) is a connective tissue disorder characterized by a disturbance in fibroblast function culminating in the telltale skin thickening and fibrosis of visceral organs including the lungs. Since the histopathogenesis of SSc is characterized by immune dysfunction and inflammation, there is good scientific rationale for using immunosuppression in this disease. However, SSc is uncommon, with an estimated prevalence ranging from 7 to 489/million and incidence from 0.6 to 122/million/year1. This rarity has undoubtedly contributed to the paucity of randomized controlled trials examining the benefit of immunosuppression in this disease. The Scleroderma Lung Study is probably the largest trial to date, with 158 patients recruited over 3.5 years from 13 centers2. Moreover, the natural history of SSc is highly variable. The course of skin involvement differs between subsets, with limited disease having a more slowly progressive course over years and decades, while skin thickening progresses gradually in the first 3–5 years of diffuse disease and may even improve in later disease3. Lung involvement is common but there is tremendous uncertainty concerning the rate of decline in lung function in SSc. Although the annual decline in forced vital capacity (FVC) in patients with early, diffuse disease had been estimated to be approximately 9% in the Scleroderma Lung Study, in fact the FVC of patients in the placebo arm fell by only 2.6% during the 1-year study2. Thus, at present, there are few trials of immunosuppressants in SSc and these trials have shown only modest benefits of immunosuppression. In a 1-year randomized placebo controlled trial of 71 patients with early (< 3 years of disease) diffuse SSc, the trend toward better modified Rodnan skin scores (range 0–51) in the methotrexate (MTX; score 21.4) compared to the placebo (score 26.3) groups … Address correspondence to Dr. M. Hudson, Jewish General Hospital, Room A-725, 3755 Cote Ste Catherine Road, Montreal, Quebec H3T 1E2. E-mail: marie.hudson{at}mcgill.ca