Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study. — CFSMEATLAS
Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study.
Retornaz, Frédérique, Rebaudet, Stanislas, Stavris, Chloé et al. · Journal of translational medicine · 2022 · DOI
Quick Summary
This study found that long-COVID patients and ME/CFS patients have very similar symptoms and muscle problems. Researchers measured electrical activity in leg muscles during and after exercise in both groups and found comparable patterns of muscle fatigue. This suggests that COVID-19 infection may trigger ME/CFS-like illness in some people.
Why It Matters
This research provides objective neuromuscular evidence that long-COVID and ME/CFS share biological mechanisms, not just subjective symptoms. For ME/CFS patients, this validates that their condition has measurable muscle dysfunction and suggests that understanding post-viral mechanisms in long-COVID may illuminate ME/CFS pathophysiology. It supports the concept that viral infections can trigger a distinct post-viral syndrome.
Observed Findings
Fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise occurred with similar frequency in long-COVID and ME/CFS groups.
Exercise-induced M-wave alterations (objective muscle membrane dysfunction) were present in comparable patterns in both groups.
Greater M-wave changes were associated with higher maximal handgrip strength and maximal exercise power in both cohorts.
Digestive problems were less common in long-COVID patients compared to ME/CFS patients.
Approximately 70% of ME/CFS patients showed neuromuscular disorders with M-wave alterations, consistent with prior literature.
Inferred Conclusions
SARS-CoV-2 infection may trigger ME/CFS-like neuromuscular illness in some patients, as evidenced by shared symptom profiles and objective muscle membrane dysfunction.
The neuromuscular abnormalities in long-COVID and ME/CFS appear to be biological phenomena, not purely psychosomatic, as demonstrated by measurable M-wave changes.
Post-viral mechanisms underlying ME/CFS may be partially explained by studying long-COVID patients, given the striking clinical and biological parallels.
Remaining Questions
What is the long-term trajectory of long-COVID patients—do symptoms and M-wave alterations persist, resolve, or progress to persistent ME/CFS?
What This Study Does Not Prove
This study does not prove that all long-COVID cases progress to ME/CFS, nor does it establish causation—only that similarities exist between the two conditions at a single timepoint. The retrospective design cannot determine whether long-COVID patients' symptoms are stable, improving, or worsening over time. It also does not identify the specific biological mechanisms causing M-wave alterations in either condition.