Occupational and Hobby Exposures Associated With Myositis Phenotypes in a National Myositis Patient Registry.

Objective: The objective of this study was to investigate occupational and hobby exposures to silica, solvents, and heavy metals and the odds of having the idiopathic inflammatory myopathy (IIM) phenotypes dermatomyositis (DM) and polymyositis (PM) versus inclusion body myositis (IBM), lung disease plus fever or arthritis (LD+), and systemic autoimmune rheumatic disease-associated overlap myositis (OM).

Methods: The sample included 1,390 patients (598 with DM, 409 with PM, and 383 with IBM) aged ≥18 years from a national registry. Of these, 218 (16%) were identified with LD+, and 166 (12%) with OM.

The Geospatial Distribution of Myositis and Its Phenotypes in the United States and Associations With Roadways: Findings From a National Myositis Patient Registry.

Background: Little is known about the spatial distribution of idiopathic inflammatory myopathies (IIM) in the United States (U.S.), or their geospatial associations.

Association of Ultraviolet Radiation Exposure With Dermatomyositis in a National Myositis Patient Registry.

Objective: Dermatomyositis (DM) has been associated with geospatial differences in ultraviolet (UV) radiation, but the role of individual determinants of UV exposure prior to diagnosis is unknown. The objective was to examine the role of those individual determinants.

Methods: We analyzed questionnaire data from 1,350 adults in a US national myositis registry (638 with DM, 422 with polymyositis [PM], and 290 with inclusion body myositis [IBM] diagnosed at ages 18-65 years), examining the likelihood of DM compared with PM and IBM diagnosis, in relation to self-reported sunburn history and job- and hobby-related sun exposures in the year prior to diagnosis.

Predictors of Reduced Health-Related Quality of Life in Adult Patients With Idiopathic Inflammatory Myopathies.

Objective: Extensive studies on health-related quality of life (HRQoL) in idiopathic inflammatory myopathies (IIMs) are lacking. Our objective was to document HRQoL and to identify factors associated with a reduced HRQoL in patients with IIM.

Methods: A total of 1,715 patients (median age 49.