E3 PreliminaryModerate confidencePEM unclearReview-NarrativePeer-reviewedMachine draft
Long COVID: mechanisms, risk factors and recovery.
Astin, Rónan, Banerjee, Amitava, Baker, Mark R et al. · Experimental physiology · 2023 · DOI
Quick Summary
This review examines Long COVID—a prolonged illness affecting some people after COVID-19 infection—and compares it to similar post-viral conditions like ME/CFS. Researchers found that Long COVID involves problems with the heart and lungs, muscle function, and how the body regulates its nervous system. The review discusses various treatment approaches being tested, including exercise programs, breathing exercises, and techniques to help calm an overactive nervous system.
Why It Matters
This review is crucial for ME/CFS patients because it explicitly connects Long COVID research with ME/CFS, highlighting shared mechanisms and treatment strategies. For the ME/CFS research community, it demonstrates how rapidly advancing Long COVID research—particularly regarding dysautonomia, oxygen delivery, and energy metabolism—provides new insights applicable to understanding chronic post-viral illnesses more broadly.
Observed Findings
- Dysautonomia and postural orthostatic tachycardia syndrome are prominent features in Long COVID affecting symptom severity and fatigue
- Cardiopulmonary exercise testing reveals alterations in peripheral muscle function, ventilatory inefficiency, and autonomic dysfunction
- Micro-clotting and disruption of cellular energy metabolism have emerged as potential mechanisms contributing to Long COVID symptoms
- Active populations (military, elite athletes) have provided valuable early research demonstrating physiological changes and potential monitoring strategies
- Vagal stimulation and other sympathetic-dampening interventions are being explored as potential treatments
Inferred Conclusions
- Long COVID shares important pathophysiological features with ME/CFS and other post-viral syndromes, suggesting research on one condition can inform management of all
- Multiple physiological systems are disrupted in Long COVID, requiring integrated treatment approaches combining rehabilitation with targeted drug interventions
- Cardiopulmonary exercise responses and monitoring protocols developed in athletic populations may be adapted to assess and guide recovery in wider Long COVID populations
- Therapeutic strategies addressing dysautonomia and impaired oxygen delivery show promise for combating Long COVID symptoms
Remaining Questions
What This Study Does Not Prove
This review does not establish new causal mechanisms through original research; it synthesizes existing literature. It does not prove that any particular treatment is definitively effective for Long COVID or ME/CFS, only that various approaches are being trialled. The comparison between Long COVID and ME/CFS remains exploratory and does not conclusively establish that both conditions share identical underlying pathophysiology.
Tags
Symptom:Post-Exertional MalaiseCognitive DysfunctionOrthostatic IntoleranceFatigue
Biomarker:MetabolomicsBlood Biomarker
Phenotype:Infection-TriggeredLong COVID Overlap
Method Flag:PEM Not DefinedExploratory Only
Metadata
- DOI
- 10.1113/EP090802
- PMID
- 36412084
- Review status
- Machine draft
- Evidence level
- Early hypothesis, preprint, editorial, or weak support
- Last updated
- 10 April 2026
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
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