Nursing

Intensive care medicine

Weakness

Surgery

Clinical trial

Polymyositis

Physical therapy

Muscle weakness

Quality of life (healthcare)

Internal medicine

Myositis

Inclusion body myositis

Dermatomyositis

Medicine

Juvenile dermatomyositis

Physical medicine and rehabilitation

Disease

Pathology

Nature Reviews Rheumatology

The idiopathic inflammatory myopathies are characterized by muscle weakness and inflammation. A range of tools are available to evaluate outcomes in the treatment of myositis, including, among others, core set measures that were developed by international networks of myositis researchers. The adult and juvenile myositis syndromes, commonly referred to collectively as idiopathic inflammatory myopathies (IIMs), are systemic autoimmune diseases with the hallmarks of muscle weakness and inflammation. Validated, well-standardized measures to assess disease activity, known as core set measures, were developed by international networks of myositis researchers for use in clinical trials. Composite response criteria using weighted changes in the core set measures of disease activity were developed and validated for adult and juvenile patients with dermatomyositis and adult patients with polymyositis, with different thresholds for minimal, moderate and major improvement in adults and juveniles. Additional measures of muscle strength and function are being validated to improve content validity and sensitivity to change. A health-related quality of life measure, which incorporates patient input, is being developed for adult patients with IIM. Disease state criteria, including criteria for inactive disease and remission, are being used as secondary end points in clinical trials. MRI of muscle and immunological biomarkers are promising approaches to discriminate between disease activity and damage and might provide much-needed objective outcome measures. These advances in the assessment of outcomes for myositis treatment, along with collaborations between international networks, should facilitate further development of new therapies for patients with IIM.

Update on outcome assessment in myositis