Safety of a home exercise programme in patients with polymyositis and dermatomyositis:: a pilot study

Objectives. To investigate whether a home exercise programme could safely be performed by patients with stable, inactive polymyositis (PM) and dermatomyositis (DM), regarding disease activity, muscle function, health status and pain. Methods. Ten patients with reduced muscle function completed the study. A home exercise programme including exercises for strength in the upper and lower limbs, neck and trunk, for mobility in the upper limbs and moderate stretching was developed. The patients exercised for 15 min and took a 15 min walk 5 days a week during a 12 week period. Assessments included clinical evaluation of disease activity, serum creatinine phosphokinase (CPK) levels, magnetic resonance imaging (MRI) of the quadriceps, repeated muscle biopsy of the vastus lateralis, a muscle function index (FI), a walking test and a health status instrument (the SF 36) performed at the start of the study and after 12 weeks. Results. After 12 weeks of exercise, there were no signs of increased disease activity as assessed clinically, by CPK values, MRI or muscle biopsy findings. On an individual basis, all patients improved regarding muscle function according to the FI, in six cases the improvement reached statistical significance (P < 0.05). A significant improvement regarding muscle function in the upper and lower limbs, walking distance and general health status was achieved. Conclusions. Our results indicate that this home exercise programme can be safely employed in patients with stable, inactive PM and DM, with beneficial effects on muscle function.