Systemic sclerosis - continuing progress in developing clinical measures of response.

Few randomized controlled trials (RCT) have shown a demonstrable treatment effect in systemic sclerosis (SSc), making it difficult to evaluate outcome measures in this disease indication. Results from recent RCT, including those evaluating cyclophosphamide for SSc interstitial lung disease and endothelin receptor antagonists for pulmonary hypertension, have allowed analysis of certain organ-specific endpoints using the OMERACT filter. An earlier metaanalysis established that skin score, measures of Raynaud's, pulmonary function tests, blood pressure, pain, Health Assessment Questionnaire, and Medical Outcomes Survey Short-Form 36 are validated outcome measures in SSc. At OMERACT 8, data regarding validation of high-resolution computed tomography of the lungs, 6-minute walk test, and patient reported outcomes in SSc were presented. A Delphi exercise to develop consensus regarding a combined set of noninvasive measures for pulmonary arterial hypertension (PAH) is under way. Given the protean nature of this illness and its multiorgan system involvement, a composite responder index may be preferable. Another Delphi exercise is designed to develop consensus regarding a combined SSc response index to be validated in future RCT.