Clinical Characteristics of Juvenile Idiopathic Inflammatory Myopathy and Comparison With Adult Patients: Analysis From a Multicentric Cohort in Spain.

METHODS: This study reviewed the medical records of patients from the REMICAM cohort, a multicentric longitudinal study carried out in patients with IIM, followed up between 1980 and 2014 in 12 hospitals in Madrid, Spain. Patients with definite or probable JPM, JDM, adult DM, and adult PM according to the modified Bohan and Peter criteria were selected. We compared the characteristics between JDM and JPM, and between JIIM and adult IIM. RESULTS: Eighty-six juvenile patients (75 JDMs and 11 JPMs) and 283 adult patients (133 DMs and 150 PMs) were included. Compared with patients with JDM, patients with JPM were older at diagnosis, had more fever and arthritis, and were less frequently treated with disease-modifying antirheumatic drugs (these differences were not statistically significant). Compared with patients with adult DM, those with JDM presented more frequently with calcinosis (33.8% vs 6.9%, p < 0.0001) and had less severe infections (4.3% vs 23.4%, p < 0.0001), malignancies (1.3% vs 25.6%, p < 0.0001), and mortality (3.5% vs 33%, p < 0.0001). Patients with JDM were treated less frequently with azathioprine (10.8% vs 44.7%, p < 0.0001). CONCLUSIONS: Our findings confirm that JIIMs are a heterogeneous group of diseases with relevant differences compared with adult IIMs.

Multicenter registry on inflammatory myositis from the Rheumatology Society in Madrid, Spain: Descriptive Analysis. / Registro de pacientes con miopatía inflamatoria de la Sociedad Madrileña de Reumatología: análisis descriptivo.

OBJECTIVE: To analyze clinical characteristics, survival and causes of death of patients diagnosed with autoimmune inflammatory myositis in the REMICAM registry from the Society of Rheumatology in the Community of Madrid (SORCOM). METHODS: Multicenter cohort of patients diagnosed with autoimmune inflammatory myopathy with follow-up between January 1980 and December 2014. A total of 313 variables concerning demographic, clinical and morbidity data were collected, and a comparison was performed between clinical subgroups. RESULTS: A total of 479 patients were recruited from 12 centers, with 14% of patients lost to follow-up. Seventy-four percent of cases were women, age at diagnosis of 44±23 years and a mean follow-up period of 10±8 years. The most frequent clinical subgroups were primary myositis (PM 29%, DM 22%), followed by overlap myositis (20.5%), juvenile myositis (18%), myositis associated with cancer (8%), immune-mediated necrotizing myositis (1%) and inclusion body myositis (1%). During the follow-up period, a total of 114 deaths (28%) were registered, the main causes being cancer (24%), infections (23%) and cardiovascular events (21%). CONCLUSIONS: A total of 479 patients were recruited in the REMICAM registry of inflammatory myopathies. Including sociodemographic, clinical and prognostic information, it represents the largest Spanish multicenter registry to date in rheumatology, and constitutes an important source for conducting further substudies.