Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-COVID Syndrome: A Common Neuroimmune Ground?
Ryabkova, Varvara A, Gavrilova, Natalia Y, Fedotkina, Tamara V et al. · Diagnostics (Basel, Switzerland) · 2022 · DOI
Quick Summary
This Russian study looked at 56 people with ME/CFS and 14 people with post-COVID syndrome to understand how their bodies function differently. The researchers found that both groups had similar patterns of immune system problems, heart rate changes when standing up, and reduced blood flow in small vessels. Importantly, fatigue severity was linked to many other ME/CFS symptoms but not to anxiety or depression.
Why It Matters
This study provides objective evidence that ME/CFS and post-COVID syndrome share common biological abnormalities in immune function and blood vessel control, supporting the view that both are neuroimmune disorders rather than purely psychological conditions. The finding that all tested ME/CFS patients had immunological abnormalities strengthens the case for ME/CFS as a physical disease with measurable biological markers.
Observed Findings
Immunological abnormalities were detected in 12/12 tested ME/CFS patients.
Postural orthostatic tachycardia prevalence was 37.5% in ME/CFS versus 75% in post-COVID ME/CFS (p=0.02 vs controls).
Laser Doppler flowmetry showed hyperemic microcirculation disorder patterns in both ME/CFS and post-COVID ME/CFS groups similar to acute inflammatory response.
Fatigue severity correlated with post-exertional exhaustion, immune dysfunction, sleep disturbances, autonomic nervous system dysfunction, and pain syndromes.
Fatigue severity did NOT correlate with anxiety or depression symptom severity.
Inferred Conclusions
ME/CFS and post-COVID syndrome share common neuroimmune pathophysiology including immune dysfunction and microcirculation abnormalities.
Postural orthostatic tachycardia is more prevalent in post-COVID ME/CFS than in classic ME/CFS.
Fatigue in ME/CFS is linked to systemic symptoms across multiple physiological domains rather than to psychiatric comorbidity.
ME/CFS has objective measurable biological markers rather than being primarily psychological in origin.
Remaining Questions
Do the identified immunological abnormalities and microcirculation changes directly cause ME/CFS symptoms, or are they consequences of the disease?
What This Study Does Not Prove
This study does not establish whether the immunological and microcirculation abnormalities cause ME/CFS symptoms or result from them. It does not prove that post-COVID syndrome always develops into ME/CFS, only that these 14 post-COVID patients met ME/CFS diagnostic criteria. The small sample size and lack of longitudinal follow-up limit generalizability to broader populations.