Hypermobility spectrum disorder/hypermobile Ehlers-Danlos syndrome, mast cell activation syndrome and dysautonomia as risk factors for adverse events and complications

Introduction Hypermobility spectrum disorder/hypermobile Ehlers-Danlos syndrome (HSD/hEDS), mast cell activation syndrome (MCAS) and dysautonomia, including postural orthostatic tachycardia syndrome (POTS), are comorbid conditions encountered in clinical practice with possible overlapping immunologic, autonomic and connective tissue abnormalities. Clinicians frequently observe that affected individuals affected with these syndromes commonly experience disproportionate adverse events and complications from a variety of stressors.Areas covered We review clinical observations and emerging evidence via PubMed on adverse events and complications experienced by patients with HSD/hEDS, MCAS and dysautonomia in response to surgery, post-operative period, anesthesia, medication side effects, substance sensitivities and infection.Expert opinion Patients with HSD/hEDS, MCAS and dysautonomia may be at a higher risk of adverse events and complications associated with surgery, medication, substances and infection. Recognition and awareness of these syndromes and the risks, which each disorder can carry alone or as a triad, may lead to risk mitigation, appropriate counseling and prognostication. Future studies should focus on longitudinal multicenter studies assessing risks and outcomes in this vulnerable patient population. Translational studies are also needed to elucidate the mechanisms underlying adverse events and complications in patients with HSD/hEDS, MCAS and dysautonomia.