The rare disease status of Ehlers-Danlos syndrome (EDS) and hypermobility spectrum disorder (HSD) should be re-evaluated, as both conditions seem to be more prevalent than previously thought, a U.K. study suggests.
A nationwide Danish cohort study  had reported that EDS, a connective tissue disorder, affects 20 per 100,000 people, an incidence that falls within the scope of a rare disease according to European Union standards (less than 50 cases in 100,000 people).
However, scientists are now convinced that the prevalence of EDS and HSD could be much higher than previously thought, because many patients are initially misdiagnosed, which can skew the estimations of disease prevalence.
This is a huge problem and also affects other unusual, subtle, multi-symptomatic illnesses or syndromes like Fibromyalgia, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and Lyme Disease.
After our symptoms have had their boxes checked in our EHR (ELectronic Heath Record), our standardized medical-insurance-finance system sends us through a standard list of possible diagnoses that starts, not unreasonably, with the most common probable causes.
There are no intuitive leaps, no clever guesses from long experience, no one to notice anything more than what’s required from a standard list of patient descriptors (pulse, respiration, BP, chief complaint) demanded by the EHR software. All subtlety has been lost.
This underestimation could be problematic, as it may make physicians less likely to consider any of these conditions when examining and diagnosing patients.
they carried out a case-control nationwide study based on the electronic medical records of patients who were diagnosed with EDS or joint hypermobility syndrome (JHS) between July 1990 and June 2017.
The study included data gathered from primary care and hospital admissions in Wales. Of note, JHS has been classified as EDS or HSD since March 2017, according to the latest classification criteria.
combined EDS/JHS incidence of 10 cases per 5,000 people (194.2 per 100,000), which is above what would be considered a rare disease following EU standards.
The team also discovered a large discrepancy in the mean age of diagnosis between genders, with men being diagnosed approximately 8.5 years earlier than women.
In addition, they found that those with EDS/JHS were likely to receive therapeutic prescriptions for other disorders (e.g. musculoskeletal, gastrointestinal, and heart diseases), and also to be diagnosed with different types of illnesses, including mental, nervous, and digestive system disorders, within a period of one year before and after being diagnosed with EDS/JHS.
“We conclude that EDS/HSD are not rare conditions, and are associated with significantly increased odds of additional diagnoses and use of medications across many body systems. There is a large gender difference in the age of diagnosis, with many women not diagnosed until adulthood,” the researchers wrote.
Author: Joana is currently completing her PhD in Biomedicine and Clinical Research at Universidade de Lisboa. She also holds a BSc in Biology and an MSc in Evolutionary and Developmental Biology from Universidade de Lisboa.
Her work has been focused on the impact of non-canonical Wnt signaling in the collective behavior of endothelial cells — cells that make up the lining of blood vessels — found in the umbilical cord of newborns.