Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2010 Jan;146(1):26-30.
doi: 10.1001/archdermatol.2009.328.

Incidence of dermatomyositis and clinically amyopathic dermatomyositis: a population-based study in Olmsted County, Minnesota

Margo J Bendewald  1 , David A Wetter, Xujian Li, Mark D P Davis
Affiliations
Comparative Study

Incidence of dermatomyositis and clinically amyopathic dermatomyositis: a population-based study in Olmsted County, Minnesota

Margo J Bendewald et al. Arch Dermatol. 2010 Jan.

Abstract

Objectives: To identify new and existing cases of dermatomyositis and its subtypes in Olmsted County, Minnesota, from 1976 through 2007, and to establish a population-based estimate of the incidence and prevalence of dermatomyositis and amyopathic dermatomyositis.

Design: Retrospective population-based study.

Setting: Community-based epidemiology project. Patients Patients with a diagnosis of dermatomyositis were identified from the Rochester Epidemiology Project.

Main outcome measures: Incidence of dermatomyositis and clinically amyopathic dermatomyositis and risk of malignancy in clinically amyopathic dermatomyositis.

Results: Of the 29 patients identified, 6 (21%) had the clinically amyopathic subtype of dermatomyositis and 22 (76%) were female. Overall age- and sex-adjusted incidence of dermatomyositis including all subtypes was 9.63 (95% confidence interval [CI], 6.09-13.17) per 1 million persons and 2.08 (95% CI, 0.39-3.77) per 1 million persons for clinically amyopathic dermatomyositis. Age- and sex-adjusted prevalence for all subtypes of dermatomyositis was 21.42 (95% CI, 13.07-29.77) per 100,000 persons. Eight patients (28%) had a malignant condition during the study period; the risk of malignancy (odds ratio) for classic dermatomyositis compared with clinically amyopathic dermatomyositis was 4.61 but was not statistically significant (95% CI, 0.22-96.09) (P=.44).

Conclusions: Dermatomyositis is a rare disease, and clinically amyopathic dermatomyositis represents an estimated 20% of all dermatomyositis cases. Larger population-based studies are needed to estimate the risk of malignancy associated with subtypes of dermatomyositis, particularly clinically amyopathic dermatomyositis.

PubMed Disclaimer

References

    1. Pearson C. Polymyositis and dermatomyositis. In: McCarty DJ, editor. Arthritis and Allied Conditions: a Textbook of Rheumatology. 9th ed. Lea & Febiger; Philadelphia: 1979. p. 742.
    1. Euwer RL, Sontheimer RD. Amyopathic dermatomyositis (dermatomyositis sine myositis): presentation of six new cases and review of the literature. J Am Acad Dermatol. 1991;24(6 Pt 1):959–966. - PubMed
    1. el-Azhary RA, Pakzad SY. Amyopathic dermatomyositis: retrospective review of 37 cases. J Am Acad Dermatol. 2002;46(4):560–565. - PubMed
    1. Finger DR, Dunn CL, Gilliland WR, James WD. Amyopathic dermatomyositis associated with malignancy. Int J Dermatol. 1996;35(9):663–664. - PubMed
    1. Nanke Y, Tateisi M, Yamagata H, Hara M, Kamatani N. [A case of amyopathic dermatomyositis with rapidly progressive interstitial pneumonia]. Ryumachi. 2000;40(4):705–710. Japanese. - PubMed

Publication types

MeSH terms