Hypermobile Ehlers-Danlos Syndrome: A Prodromal Subtype of Functional Movement Disorders?

The phenotypic diversity of functional movement disorders (FMD) is considered a reflection of its many etiological subtypes. Ehlers-Danlos syndrome (EDS), a joint hypermobility syndrome, also has variable phenotypes, which may include functional symptoms.

To determine the prevalence of combined diagnoses of FMD and EDS.

We searched our Electronic Medical Records for patients carrying diagnostic codes for EDS and FMD. Further data extraction was done through chart review.

Of 11,621 patients evaluated from January 1, 2016 to May 1, 2022, 16 carried a diagnosis of EDS, of which 9 (56.3%) were also diagnosed with FMD. Conversely, a diagnosis of FMD was documented in 190 (1.6%), of whom 16 (8.4%) were diagnosed with EDS. In all EDS-FMD cases, the diagnosis of EDS preceded the onset and diagnosis of FMD.

The co-occurrence of FMD and EDS is beyond chance, suggesting association. EDS may represent a prodromal subtype of, and share common pathophysiologic features with, FMD.