Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients. — CFSMEATLAS
Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients.
van Campen, C Linda M C, Visser, Frans C · Healthcare (Basel, Switzerland) · 2022 · DOI
Quick Summary
This study compared patients with long-haul COVID to two groups of ME/CFS patients (those who got sick after Epstein-Barr virus infection and those who became ill gradually) to understand a common symptom called orthostatic intolerance—dizziness or fainting when standing up. Researchers found that long-haul COVID patients had similar symptoms and physical responses to standing as ME/CFS patients, and all three groups showed comparable problems with blood flow and heart function during the standing test. The findings suggest that long-haul COVID and ME/CFS may be essentially the same underlying condition.
Why It Matters
This research provides objective physiological evidence that long-haul COVID and ME/CFS share nearly identical orthostatic dysfunction mechanisms, which could unify clinical understanding and treatment approaches for both conditions. Demonstrating comparable pathophysiology validates that long-haul COVID patients' experiences are not psychogenic and deserve the same medical recognition and research attention as ME/CFS. The findings suggest that insights about one condition may directly apply to the other.
Observed Findings
Long-haul COVID patients had 100% POTS prevalence compared to 43% in post-EBV ME/CFS and 50% in insidious-onset ME/CFS patients (p=0.0002).
No significant differences were found between the three groups in overall orthostatic intolerance prevalence, despite POTS prevalence differences.
Heart rate and blood pressure changes during tilt testing were comparable across all three patient groups.
Cerebral blood flow changes during tilt testing showed no significant differences between long-haul COVID and ME/CFS patients.
Cardiac index reduction during tilt testing was similar across all three groups.
Inferred Conclusions
Long-haul COVID patients demonstrate the same physiological orthostatic dysfunction patterns as ME/CFS patients on objective testing.
Orthostatic intolerance symptomatology and measurable abnormalities are comparable between long-haul COVID and both ME/CFS subgroups.
Long-haul COVID is essentially the same disease entity as ME/CFS based on orthostatic dysfunction characteristics.
Remaining Questions
Why do long-haul COVID patients show 100% POTS prevalence while ME/CFS groups show significantly lower rates, and what accounts for this difference if the diseases are essentially identical?
What This Study Does Not Prove
This study does not establish causality or prove that long-haul COVID definitively causes the same pathophysiological process as ME/CFS—it only shows similar outcomes on specific tests. The small sample size (14 per group) limits generalizability, and the findings cannot determine whether the diseases share identical underlying mechanisms or merely produce similar end-stage manifestations. The 100% POTS prevalence in long-haul COVID compared to lower rates in ME/CFS groups actually suggests potential differences that warrant further investigation.
Tags
Symptom:Orthostatic IntoleranceFatigue
Biomarker:Blood Biomarker
Phenotype:Infection-TriggeredLong COVID Overlap
Method Flag:PEM Not DefinedSmall SampleMixed Cohort
What causes the orthostatic intolerance in these conditions at the cellular and molecular level?
Do long-haul COVID and ME/CFS patients show similar abnormalities in other disease domains beyond orthostatic dysfunction (e.g., immune function, metabolic abnormalities)?
Would larger, prospective studies confirm these findings, and can specific biomarkers distinguish long-haul COVID from ME/CFS where clinical overlap exists?