Variant connective tissue (joint hypermobility) and dysautonomia are associated with multimorbidity at the intersection between physical and psychological health.

The symptoms of joint hypermobility extend beyond articular pain. Hypermobile people commonly experience autonomic symptoms (dysautonomia), and anxiety or related psychological issues. We tested whether dysautonomia might mediate the association between hypermobility and anxiety in adults diagnosed with mental health disorders and/or neurodevelopmental conditions (hereon referred to as patients), by quantifying joint hypermobility and symptoms of autonomic dysfunction. Prevalence of generalized joint laxity (hypermobility) in 377 individuals with diagnoses of mental health disorders and/or neurodevelopmental conditions was compared to prevalence recorded in the general population. Autonomic symptom burden was compared between hypermobile and non-hypermobile patients. Mediation analysis explored relationships between hypermobility, autonomic dysfunction, and anxiety. Patient participants had elevated prevalence of generalized joint laxity (38%) compared to the general population rate of 19% (odds ratio: 2.54 [95% confidence interval: 2.05, 3.16]). Hypermobile participants reported significantly more autonomic symptoms. Symptoms of orthostatic intolerance mediated the relationship between hypermobility and diagnosis of an anxiety disorder. Patients with mental health disorders and/or neurodevelopmental conditions have high rates of joint hypermobility. Accompanying autonomic dysfunction mediates the association between joint hypermobility and clinical anxiety status. Increased recognition of this association can enhance mechanistic understanding and improve the management of multimorbidity expressed in physical symptoms and mental health difficulties.

Joint Hypermobility Links Neurodivergence to Dysautonomia and Pain.

OBJECTIVES: Autism, attention deficit hyperactivity disorder (ADHD), and tic disorder (Tourette syndrome; TS) are neurodevelopmental conditions that frequently co-occur and impact psychological, social, and emotional processes. Increased likelihood of chronic physical symptoms, including fatigue and pain, are also recognized. The expression of joint hypermobility, reflecting a constitutional variant in connective tissue, predicts susceptibility to psychological symptoms alongside recognized physical symptoms. Here, we tested for increased prevalence of joint hypermobility, autonomic dysfunction, and musculoskeletal symptoms in 109 adults with neurodevelopmental condition diagnoses. METHODS: Rates of generalized joint hypermobility (GJH, henceforth hypermobility) in adults with a formal diagnosis of neurodevelopmental conditions (henceforth neurodivergent group, n = 109) were compared to those in the general population in UK. Levels of orthostatic intolerance and musculoskeletal symptoms were compared to a separate comparison group (n = 57). Age specific cut-offs for GJH were possible to determine in the neurodivergent and comparison group only. RESULTS: The neurodivergent group manifested elevated prevalence of hypermobility (51%) compared to the general population rate of 20% and a comparison population (17.5%). Using a more stringent age specific cut-off, in the neurodivergent group this prevalence was 28.4%, more than double than the comparison group (12.5%). Odds ratio for presence of hypermobility in neurodivergent group, compared to the general population was 4.51 (95% CI 2.17-9.37), with greater odds in females than males. Using age specific cut-off, the odds ratio for GJH in neurodivergent group, compared to the comparison group, was 2.84 (95% CI 1.16-6.94). Neurodivergent participants reported significantly more symptoms of orthostatic intolerance and musculoskeletal skeletal pain than the comparison group. The number of hypermobile joints was found to mediate the relationship between neurodivergence and symptoms of both dysautonomia and pain. CONCLUSIONS: In neurodivergent adults, there is a strong link between the expression of joint hypermobility, dysautonomia, and pain, more so than in the comparison group. Moreover, joint hypermobility mediates the link between neurodivergence and symptoms of dysautonomia and pain. Increased awareness and understanding of this association may enhance the management of core symptoms and allied difficulties in neurodivergent people, including co-occurring physical symptoms, and guide service delivery in the future.