Long COVID Is Not a Functional Neurologic Disorder
Abstract
:1. Introduction
2. Pathobiological Disease Characterization: From Neurasthenia to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome
3. Psychosomatic/Sociogenic Illness Construction: From Neurasthenia to Functional Neurologic Disorder
- One or more symptoms of altered voluntary motor behavior or sensory function
- Clinical findings provide evidence of incompatibility between the symptom and recognized neurological or medical conditions
- The symptom or deficit is not better explained by another medical or mental disorder
- The symptom or deficit causes clinically significant distress or impairment in social, occupational, or other important areas of functioning, or warrants medical evaluation
4. Evidence Refutes That Long COVID Should Be Considered a Functional Neurologic Disorder
- Autonomic conditions, such as neurocardiogenic syncope, postural orthostatic tachycardia syndrome, orthostatic intolerance, and autonomic and small fiber neuropathy
- Chronic pain conditions, such as fibromyalgia, myofascial pain syndrome, and complex regional pain syndrome
- Systemic immune conditions, such as mast cell activation syndrome and mastocytosis
- Autoimmune conditions, such as Sjögren’s syndrome, systemic lupus erythematosus, and anti-phospholipid syndrome
- Genetic conditions, such as hypermobile Ehlers-Danlos syndrome and other hypermobility spectrum disorders, Fabry’s disease and others
- Mitochondrial and metabolic conditions
- Infection-associated chronic conditions, such as myalgic encephalomyelitis, Long COVID/Post-COVID condition, and post-treatment Lyme disease
4.1. Refutative Evidence from Pathophysiology
4.2. Refutative Evidence from Clinical Presentation
4.2.1. Motor Examination
Findings | Long COVID | Functional Neurological Disorder |
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4.2.2. Sensory Examination
4.2.3. Tremor
4.2.4. Spells and Seizures
4.2.5. Gait Examination
4.2.6. Urinary Functioning
4.2.7. Cognition
4.2.8. Summary
4.3. Refutative Evidence from Neuroimaging
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Clinical Feature | ME/CFS | Long COVID | FND |
---|---|---|---|
Post-exertional malaise/ Post-exertional neuroimmune exhaustion | Yes | Yes, some types | No |
Pain | Yes | Yes, some types | Sometimes |
Dizziness | Yes | Yes | No |
Neuropathic features | Yes | Yes | No |
Recurrent flu-like symptoms | Yes | Common | No |
Dysautonomia | Yes | Common | No |
Abnormal sleep study | Yes | Yes | No |
Fatigue | Yes | Yes | Yes |
Impaired sleep | Yes | Yes | Yes |
Functional leg weakness | No | No | Yes |
Functional seizures | No | No | Yes |
Functional tremor | No | No | Yes |
Functional dystonia | No | No | Yes |
Functional gait disorder | No | No | Yes |
Functional facial spasm | No | No | Yes |
Functional tics | No | No | Yes |
Functional drop attacks | No | No | Yes |
Functional sensory symptoms | No | No | Yes |
Functional cognitive symptoms | No | No | Yes |
Functional speech and swallowing | No | No | Yes |
Functional visual symptoms | No | No | Yes |
Dissociative symptoms | No | No | Yes |
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Davenport, T.E.; Blitshteyn, S.; Clague-Baker, N.; Davies-Payne, D.; Treisman, G.J.; Tyson, S.F. Long COVID Is Not a Functional Neurologic Disorder. J. Pers. Med. 2024, 14, 799. https://doi.org/10.3390/jpm14080799
Davenport TE, Blitshteyn S, Clague-Baker N, Davies-Payne D, Treisman GJ, Tyson SF. Long COVID Is Not a Functional Neurologic Disorder. Journal of Personalized Medicine. 2024; 14(8):799. https://doi.org/10.3390/jpm14080799
Chicago/Turabian StyleDavenport, Todd E., Svetlana Blitshteyn, Nicola Clague-Baker, David Davies-Payne, Glenn J. Treisman, and Sarah F. Tyson. 2024. "Long COVID Is Not a Functional Neurologic Disorder" Journal of Personalized Medicine 14, no. 8: 799. https://doi.org/10.3390/jpm14080799