Possible involvement of the autonomic nervous system in cervical muscles of patients with myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS). — CFSMEATLAS
Possible involvement of the autonomic nervous system in cervical muscles of patients with myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS).
Matsui, Takayoshi, Hara, Kazuhiro, Iwata, Makoto et al. · BMC musculoskeletal disorders · 2021 · DOI
Quick Summary
This study looked at 1,226 hospitalized ME/CFS patients who received daily physical therapy focused on neck muscles. About 55% of patients recovered from ME/CFS after this treatment, and those who recovered showed changes in pupil size suggesting their nervous system function improved. The findings suggest that neck muscle problems and nervous system dysfunction may be connected in ME/CFS.
Why It Matters
This study provides evidence that ME/CFS may involve autonomic nervous system dysfunction in cervical muscles, offering a potential mechanistic insight into why some patients respond to localized treatment. The moderate recovery rate and detailed symptom tracking could inform rehabilitation approaches for hospitalized ME/CFS patients.
Observed Findings
55.5% of hospitalized ME/CFS patients recovered after daily cervical muscle physical therapy
Individual symptom recovery rates varied widely (36.6%-86.9%), but ME/CFS recovery rates were consistent across symptom subgroups (52.3%-55.8%)
Patients who recovered from ME/CFS had more constricted pupil diameter than those who did not recover, suggesting autonomic nervous system changes
Recovery rates of all eight symptoms showed strong associations with ME/CFS recovery (p < 0.001)
Recovery did not differ significantly by patient sex, age group, or length of hospitalization
Inferred Conclusions
Autonomic nervous system dysfunction in cervical muscles may be involved in ME/CFS pathophysiology
Localized cervical muscle treatment may improve ME/CFS through autonomic nervous system amelioration
ME/CFS and its associated symptoms may share a common underlying mechanism related to autonomic function
Remaining Questions
Does cervical muscle dysfunction cause autonomic dysfunction, or is it a secondary consequence of ME/CFS?
Why did only 55% of patients recover, and what differentiates responders from non-responders at baseline?
What This Study Does Not Prove
This observational study does not prove that cervical muscle dysfunction causes ME/CFS, only that treatment correlated with recovery in this specific hospitalized population. The study cannot determine whether pupil changes cause recovery or are a marker of recovery. Results may not apply to ambulatory or less severe ME/CFS patients, as participants were treatment-resistant inpatients.