Defining the Chronic Complexities of hEDS and HSD: A Global Survey of Diagnostic Challenges, Life-Long Comorbidities, and Unmet Needs.

Hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSDs) are prevalent, complex conditions marked by chronic pain, joint instability, and multisystem involvement. Despite affecting an estimated 1 in 500 individuals, these conditions remain poorly understood and inconsistently diagnosed. This study aimed to define their clinical burden through a large-scale, international survey. A cross-sectional, anonymous survey was distributed globally from September 2023 to March 2024. Of 9258 responses, 3906 met inclusion criteria (hEDS: n = 3360; HSD: n = 546). The 418-item questionnaire assessed symptoms, comorbidities, healthcare utilization, and quality of life. The 95% confidence intervals (CIs) were calculated for comparison. Participants with hEDS reported a mean of 24 comorbid conditions and an average diagnostic delay of 22.1 years. Common diagnoses included gastrointestinal disorders (84.3% [95% CI: 98.3-99.2%]), dysautonomia (71.4% [95% CI: 69.9-72.9%]), and chronic pain (98.9% [95% CI: 98.3-99.2%]). In contrast, HSD respondents reported a mean of 17 comorbidities, a 17.5-year time to diagnosis, and lower rates of key complications. Triggering events, such as puberty and infections were commonly reported preceding hEDS or HSD symptom onset. Comparison to the All of Us dataset revealed significantly elevated prevalence ratios of neurological, immune, and autonomic diagnoses. This global survey highlights the extensive multisystemic burden and diagnostic delays faced by individuals with hEDS and HSDs. The high prevalence of immune, neurological, gastrointestinal, and autonomic dysfunctions challenges the notion of these conditions as isolated connective tissue disorders. These findings highlight the need for updated diagnostic frameworks and mechanistic studies that explore multifactorial etiologies beyond the connective tissue paradigm.