No relevant excess prevalence of myotonic dystrophy type 2 in patients with suspected fibromyalgia syndrome

Neuromuscul Disord. 2016 Jun;26(6):370-3. doi: 10.1016/j.nmd.2016.03.009. Epub 2016 Apr 6.


Myotonic dystrophy type 2 (DM2) is a rare, autosomal dominant, multisystem disorder with proximal weakness, myotonia, pain and cataract as important symptoms. Given the assumed underreporting of DM2 in the Netherlands combined with the predominant role of pain in DM2 as well as in fibromyalgia syndrome (FMS), we hypothesized there will be an excess prevalence of DM2 in patients with (suspected) FMS. Our objective was to determine the prevalence of DM2 in patients with suspected FMS. A prevalence of 2% was considered a relevant excess frequency. Between November 2011 and April 2014, 398 patients with suspected FMS who had been assessed by a rheumatologist participated in this cross-sectional study. 95% of the study population was female, with a mean age of 42 years. The final ICD-9 diagnoses were collected, in 96% the diagnosis was FMS. 92% met the 2010 American College of Rheumatology (ACR) diagnostic criteria for FMS. A questionnaire including neuromuscular symptoms was completed. Creatine kinase was determined, and genetic testing for DM2 was conducted in all patients. DM2 was established in only one patient (0.25%, 95% CI 0.04-1.4%), thus disapproving our hypothesis of a relevant prevalence of 2%. Our results suggest that patients with suspected FMS should not routinely be tested for DM2.

Keywords: Fibromyalgia syndrome; Myotonic dystrophy type 2; Pain; Prevalence studies.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Creatine Kinase / metabolism
  • Cross-Sectional Studies
  • Female
  • Fibromyalgia / complications*
  • Fibromyalgia / enzymology
  • Fibromyalgia / epidemiology*
  • Fibromyalgia / genetics
  • Humans
  • Male
  • Middle Aged
  • Myotonic Dystrophy / complications*
  • Myotonic Dystrophy / enzymology
  • Myotonic Dystrophy / epidemiology*
  • Myotonic Dystrophy / genetics
  • Prevalence
  • RNA-Binding Proteins / genetics
  • Young Adult


  • CNBP protein, human
  • RNA-Binding Proteins
  • Creatine Kinase