Long-term prognosis of 69 patients with dermatomyositis or polymyositis.

Abstract

High mortality occurred in the first year, and the survival rate decreased continually up to 9 years. The main prognostic factor for death is old age, but dermatomyositis and polymyositis must be considered separately. General features (pulmonary fibrosis, cancer, asthenia-anorexia) are involved in dermatomyositis, whereas muscular symptoms are the most significant in polymyositis. The long-term functional prognosis was fairly good, except for generalized calcinosis, which tended to occur in childhood dermatomyositis.