Systemic Sclerosis-Associated Myopathy in a Large Single-Center Cohort: Autoantibody Profiles, Histologic Features,...

Area of Science:

• Rheumatology
• Immunology
• Neurology

Background:

• Skeletal myopathy is a frequent complication in systemic sclerosis (SSc).
• Clinical manifestations and long-term outcomes of SSc-associated myopathy are not well understood.
• Characterizing myopathy in SSc is crucial for understanding disease progression and patient prognosis.

Purpose of the Study:

• To characterize patients with skeletal myopathy in systemic sclerosis (SSc).
• To define the impact of skeletal myopathy on survival in SSc patients.
• To identify clinical and autoantibody profiles associated with SSc myopathy.

Main Methods:

• Retrospective cohort study of patients from the Johns Hopkins Scleroderma Center Research Registry.
• Comparison of clinical data, autoantibody profiles, and muscle histopathology between patients with and without skeletal myopathy.
• Survival analyses using Cox proportional hazards and regression models.

Main Results:

• Skeletal myopathy was identified in 17% of 3,919 SSc patients.
• Myopathy patients were more often diffuse SSc subtype, African-American, and had shorter disease duration.
• Anti-PM-Scl, U3RNP, and anti-Ku antibodies were associated with myopathy; anti-centromere was protective.
• Myopathy independently increased mortality risk (HR 1.60, p<0.0001) even after controlling for confounders.

Conclusions:

• Skeletal myopathy in SSc is associated with distinct clinical and autoantibody profiles.
• Myopathy in SSc patients independently increases the risk of mortality.
• Early detection and further research into myopathy's impact on outcomes are vital for improving SSc patient survival and therapies.