To determine the clinical impact of muscle involvement in a large systemic sclerosis (SSc) cohort.
Using the Canadian Scleroderma Research Group (CSRG) database, SSc patients with either elevated creatine kinase (CK) or a prior history of myositis/myopathy were identified. Regression and Kaplan-Meier analyses were performed to determine characteristics associated with muscle involvement in SSc and survival outcome.
In 1145 patients with SSc, 5.6% had an elevated CK. This subset was more likely to be male (24.5% in elevated CK vs. 12.6% in normal CK, p