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

Document Type

Journal Article

Publication Date



Arthritis Care Res (Hoboken)




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.

METHODS: We analyzed questionnaire data from 1350 adults in a U.S. national myositis registry (638 with DM, 422 polymyositis [PM], and 290 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. We estimated odds ratios (OR) and 95% confidence intervals (CI) using logistic regression adjusted for age, skin tone, and sex, to determine the association of individual UV exposures with DM diagnosis. We also evaluated the proportion of DM by maximum daily ambient UV exposure, based on UV-B erythemal irradiances for participant residence the year prior to diagnosis.

RESULTS: DM was associated with sunburn in the year before diagnosis (two or more sunburns, OR=1.77; 95%CI 1.28, 2.43 vs. PM/IBM; one sunburn OR=1.44; 95%CI 1.06, 1.95) and with having elevated job- or hobby-related sun exposure (high OR=1.64; 95%CI 1.08, 2.49 or moderate exposure OR=1.35; 95%CI 1.02, 1.78 vs. low or no exposure). Ambient UV intensity was associated with DM in females (beta=3.97, P=0.046), but not overall.

CONCLUSION: Our findings suggest that high or moderate personal exposure to intense sunlight is associated with developing DM compared with other types of myositis. Prospective research on UV exposure as a modifiable risk factor for DM is warranted. This article is protected by copyright. All rights reserved.


This is an open access PubMed Central article.

Peer Reviewed


Open Access


Find in your library