Orthostatic Symptoms and Reductions in Cerebral Blood Flow in Long-Haul COVID-19 Patients: Similarities with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.
Campen, C Linda M C van, Rowe, Peter C, Visser, Frans C · Medicina (Kaunas, Lithuania) · 2021 · DOI
Quick Summary
This study compared people with long-haul COVID-19 to people with ME/CFS to see if they experience similar problems with dizziness and blood flow when standing up. Researchers found that long-haul COVID patients had very similar symptoms to ME/CFS patients and showed even greater reductions in blood flow to the brain during tilt testing. The findings suggest that COVID-19 infection may trigger ME/CFS-like illness in some people.
Why It Matters
This study provides direct evidence that long-haul COVID and ME/CFS share similar clinical features and hemodynamic abnormalities, suggesting SARS-CoV-2 may trigger ME/CFS development. Understanding these overlaps could help clinicians recognize and appropriately manage post-viral illnesses and may guide research into common pathological mechanisms.
Observed Findings
All 10 long-haul COVID-19 patients developed POTS during head-up tilt testing.
Cerebral blood flow and cardiac index were significantly more reduced in all three patient groups compared to healthy controls.
Long-haul COVID patients showed larger cerebral blood flow reductions than ME/CFS patients with normal heart rate and blood pressure responses to tilt.
Symptom prevalence on ME/CFS questionnaires was not significantly different between long-haul COVID and ME/CFS patient groups.
Cardiac index reduction was similar across the three patient groups despite differences in heart rate/blood pressure responses.
Inferred Conclusions
Long-haul COVID-19 and ME/CFS share similar symptom profiles and hemodynamic abnormalities during orthostatic stress.
SARS-CoV-2 infection may act as a trigger for ME/CFS development, similar to SARS-CoV-1.
The early onset of orthostatic intolerance and high pre-illness activity levels in long-haul COVID patients suggest POTS is not due to deconditioning.
Cerebral blood flow dysregulation appears to be a key feature of both long-haul COVID and ME/CFS during orthostatic stress.
Remaining Questions
Do long-haul COVID patients progress to meet formal ME/CFS diagnostic criteria over time, and what proportion develop chronic ME/CFS?
What This Study Does Not Prove
This study does not prove that COVID-19 definitively causes ME/CFS, only that similarities exist between the two conditions. The small sample size and cross-sectional design limit generalizability. The study does not establish whether the cerebral blood flow reductions cause the symptoms or are secondary findings.
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 →
Contribute
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What are the underlying mechanisms causing the cerebral blood flow reductions—are they related to viral persistence, autoimmunity, autonomic dysfunction, or other pathology?
Why do some COVID-19 patients develop these orthostatic symptoms while others do not, and what are the risk factors?
Would treatments targeting orthostatic intolerance or cerebral blood flow dysregulation be effective for long-haul COVID patients?