Background/Purpose: The aim of this study is to evaluate disease course of systemic sclerosis (SSc) patients participating in a single centre multidisciplinary health-care program over one year of follow-up, and to evaluate which baseline variables discriminate patients with progressive disease.

Methods: Baseline characteristics and one year follow-up results from patients with diffuse cutaneous SSc (DcSSc), or limited (cutaneous) SSc (L(c)SSc) referred to the multidisciplinary health-care program were evaluated. Progressive disease was defined as: SSc-related decease, decrease of ≥10% of forced vital capacity (FVC), decrease of ≥15% of diffusing capacity for carbon monoxide (DLCO), decrease of ≥10% of body weight, decrease of ≥ 30% of estimated glomerular filtration rate, increase of ≥30% modified Rodnan Skin Score (mRSS) (with D ≥3) or ≥0.25 increase of Scleroderma Health Assessment Questionnaire. The number of patients with progressive disease was determined. Logistic regression analysis was used to determine the association between baseline characteristics and presence of progressive disease. Discriminative ability of the multivariable model was expressed as the area under the receiver operating characteristic (AUC) curve.

Results: Between April 2009 and January 2014 303 SSc patients were referred to the health-care program, of which 164 underwent re-evaluation after one year (mean 13.5, range 10-23 months). Sixty-six patients (38% of 172) had progressive disease, including 8 patients who died ≤18 months after first evaluation. Progressive disease was found in 27 (33%) patients with DcSSc, 32 (50%) with LcSSc, and seven (26%) with LSSc (Table 1). Type of skin involvement, mRSS and disease duration could not independently discriminate progressive patients. Multivariable analysis showed that friction rubs and proximal muscular weakness were most significantly associated with progressive disease, additional to type of SSc, age, gender, disease duration, autoantibody profile and use of immunosuppressive therapy. The multivariable model showed fair discrimination (AUC 0.718 [95% CI 0.636-0.800]).

Conclusion: Thirty-eight percent of SSc patients showed progressive disease after one year follow-up, with highest frequency of progression among patients with LcSSc. The strongest predictors of progressive disease were friction rubs and proximal muscular weakness; pattern of skin involvement and disease duration were not independently discriminative. These observations underline the relevance of strict follow-up in all SSc patients as well as the need for more effective treatment strategies.