Involvement of Cervical Muscle Lesions and Autonomic Nervous System in Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS)

Abstract Background: Patients with myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) sometimes coincide with stiffness of cervical muscles. This study examined the effect of local modulation of the cervical muscles on ME/CFS and the underlying mechanism.Methods: In total, 1,226 inpatients with ME/CFS who were resistant to outpatient care were enrolled in this study for 11 years. All patients underwent daily physical therapies to the cervical muscles during hospitalization. Self-rated records documenting the presence and absence of ME/CFS and the representative eight disorders that frequently accompany it at admission and discharge were compared. The pupil diameter was also measured to examine involvement of autonomic nervous system function.Results: The recovery rate of ME/CFS after local therapy was 55.5%, and did not differ significantly by sex, age strata, and hospitalization period. The recovery rates of the eight disorders were variable (36.6－86.9%); however, those of ME/CFS in the disorder subpopulations were similar (52.3－55.8%). The recovery rates of all disorders showed strong associations with that of ME/CFS (p<0.001). The pupil diameter was decreased at discharge, and the change was significantly higher in the ME/CFS-recovered patients than ME/CFS-unrecovered patients in the total population and the subpopulations stratified by sex, age, and hospitalization period.Conclusions: Local therapy to the cervical muscles led to recovery in more than half of patients with ME/CFS, at least partly through amelioration of the autonomic nervous system. There may be a causal relationship between recoveries of ME/CFS and these related whole-body disorders.Trial registration ID: UMIN000036634. Registered 1 May 2019 - Retrospectively registered, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/index.cgi