Brain and Body Interaction

Common presentations include gastrointestinal symptoms with no diagnosis, or which have been labelled as IBS, migraines, chronic unexplained pain, unexplained urticaria, chronic fatigue, low mood and anxiety.  ADHD is a consequence of dopamine and noradrenaline dysfunction in brain pathways; ADHD medications specifically target these.  There are established associations between this dopamine/noradrenaline dysfunction and with Ehlers-Danlos syndromes/hypermobility spectrum disorders.  Associations are also established between neurodivergence, substance misuse, eating disorders, obesity, allergies and atopy, autoimmunity, apnoea, epilepsy, migraine and chronic pain. he presentations previously discussed are therefore linked, are associated with neurodiversity, and may be driven by hypermobility, orthostatic hypotension, and altered immunity. The ‘All Brains Belong’ website, hosted by ADHD and autism professionals in Vermont, summarises the evidence in this area, which is still evolving.

‍CLICK HERE for an extremely useful resource for clinicians to find out more about the constellation of chronic medical conditions commonly seen in Autistic & ADHD Adults (courtesy of All Brains Belong)

Connecting brain and body: Transdiagnostic relevance of connective tissue variants to neuropsychiatric symptom expression². [orange text = putative mechanisms]

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This diagram illustrates the possible pathways for the links between collagen laxity and neurodevelopmental differences and the aetio-pathogeneis of associated physical and mental health conditions. It is postulated that variant connective tissue (i.e. not ‘just’ bendy joints) predisposes to mast cell activation disorder and dysautonomia which in turn can lead to gastrointestinal dysfunction, autoimmunity and neuropsychiatric differences.  The mechanisms by which these occur are not known but may be related to brain under-perfusion, consequent oxidative stress, dysautonomia, neuroinflammation and neurotransmitter dysfunction³

How is this relevant to front-line general practice?

Neurodivergence is linked with somatic syndromes.

Practising GPs could consider the following:

• Screen patients who present with unexplained symptoms, or in whom you suspect a connective tissue disorder, for neurodivergent conditions, relevant associated physical conditions, and refer onwards.
• Encourage patients to discuss what they have learnt with their relatives, particularly first-degree relatives, being aware that neurodivergence is strongly heritable.
• Current primary care funding and time issues often stop us exploring links in as much detail as we would like to; referring can feel futile when the wait for an assessment for ADHD or autism is often measured in years of months. BAND would like to spread awareness, facilitate education with mentoring and supervision, explore alternative models of care and encourage more lateral thinking that is inspired by evidence-based research.

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References

[1] Everything is Connected to Everything: Improving the Healthcare of Autistic & ADHD Adults. All Brains Belong. Everything is Connected to Everything: Improving the Healthcare of Autistic & ADHD Adults - All Brains Belong VT

[2] Sharp HEC, Critchley HD, Eccles JA. Connecting brain and body: Transdiagnostic relevance of connective tissue variants to neuropsychiatric symptom expression. World J Psychiatr 2021; 11(10): 805-820 [PMID: 34733643 DOI: 10.5498/wjp.v11.i10.805].  Used under licence CC BY-NC 4.0.

[3] Kustow J. Attention difficulties: The relationship between Ehlers-Danlos syndromes/hypermobility spectrum disorders and attention difficulties, “brain fog,” and attention-deficit hyperactivity disorder (ADHD). In: CA Francomano, AJ Hakim, LGS Henderson et al. The Symptom-Based Handbook for Ehlers-danlos Syndromes and Hypermobility Spectrum Disorders. Elsevier, 2024, pp 135-54