OBJECTIVE: To report the results of a retrospective cohort involving 139 patients with dermatomyositis, conducted from 1991 to 2011. METHODS: All patients met at least four of the five Bohan and Peter criteria (1975). RESULTS: The patients' mean age at disease onset was 41.7 ± 14.1 years, and mean disease duration was 7.2 ± 5.2 years. The sample comprised 90.2% white patients and 79.9% female patients. Constitutional symptoms occurred in less than half of the patients. Cutaneous and joint involvements occurred in 95.7% and 41.7% of the patients, respectively. Incipient pneumopathy, ground glass opacities and/or pulmonary fibrosis were present in 48.2% of the patients. All patients received prednisone (1 mg/kg/day) and 51.1% also received intravenous methylprednisolone (1 g/day for three days). Several immunosuppressants were used as corticosteroid sparing agents according to tolerance, side effects and/or refractoriness. Although disease relapse (clinical and/or laboratory) occurred in 53.2% of the patients, 76.3% were in disease remission at the end of the study. The rate of severe infection was 35.3%, and herpes zoster predominated. There were 15 (10.8%) cases of cancer, 12 within one year after the diagnosis. There were 16 deaths (11.5%), and their major causes were sepsis/septic shock (27.5%), pneumopathy attributed to the disease (31.3%), neoplasms (31.3%), and cardiovascular events (12.5%). CONCLUSIONS: In this study, the clinical and laboratory data were similar to those of other population groups described in the literature, with minimal differences regarding the frequency and characteristics of the extramuscular manifestations.
dermatomyositis; myositis; epidemiology
