5th June 2025

Prognosis

Classic dermatomyositis has a 5-year survival of 95% and 10-year survival of 84%. Despite improved survival rates with newer treatments, one third of patients will suffer from permanent disability. Classic dermatomyositis has a relapsing-remitting course and patients will require long-term treatment. 

Amyopathic dermatomyositis have a good response to treatment of myopathy, but cutaneous disease is often more resistant to treatment. Follow-up is required to check for any myopathy, but prognosis is overall good.

Poor prognostic factors include

• Delay in treatment of more than 6 months after symptom onset
• Presenting with greater muscle weakness
• Respiratory muscle involvement
• ILD
• Dysphagia
• Malignancy
• Cardiac involvement