Skin thickness score as a predictor and correlate of outcome in systemic sclerosis - High-dose versus low-dose penicillamine trial

Objective. To study the clinical implications of a skin thickness score gre ater than or equal to 20 at first visit and of softening of sclerodermatous skin in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneo us scleroderma. Methods. Skin and visceral involvement were assessed in 134 SSc patients wi th diffuse scleroderma (mean +/- SD duration of SSc 10 +/- 4 months) as the y entered a multicenter drug trial and again at 2 years of followup, Advent of mortality and scleroderma renal crisis (SRC) were assessed during a fol lowup of 4.0 +/- 1.1 years (mean +/- SD). Logistic and linear regression we re used to examine the relationship of baseline skin score to morbidity, mo rtality, and visceral involvement and the relationship of changes in skin s core to changes in physical examination, laboratory, and functional variabl es over 2 years. Results. A baseline skin score greater than or equal to 20 was associated w ith heart involvement at baseline (odds ratio [OR] 3.10, 95% confidence int erval [95% CI] 1.25-7.70) and was predictive of mortality (OR 3.59, 95% CI 1.23-10.55) and SRC (OR 10.00, 95% CI 2.21-45.91) over 4 years. Multivariat e linear regression demonstrated that a model with skin score at baseline ( P = 0.0078) and changes in large joint contractures (P = 0.0072), tender jo int counts (P = 0.0119), handspread (P = 0.0242), and Health Assessment Que stionnaire disability index (HAQ-DI) (P = 0.0244) explained the change in s kin score over 2 years (R-2 = 0.567), Multivariate logistic regression demo nstrated that the investigator's global assessment of improvement was best explained by a model with skin score and HAQ-DI (R-2 = 0.455). Conclusion. A baseline skin score greater than or equal to 20 was associate d with heart involvement at baseline and predicted mortality and SRC over t he subsequent 4 years. Improvement in skin score in these patients with dif fuse cutaneous scleroderma was associated with improvement in hand function , inflammatory indices, joint contractures, arthritis signs, overall functi onal ability, and the examining investigator's global assessment of improve ment.