Ying-Chih, Cheng, Yu-Chen, Huang, Wei-Lieh, Huang · Neuroscience and biobehavioral reviews · 2020 · DOI
This large review combined results from 85 studies comparing heart rhythm patterns between people with conditions like fibromyalgia and ME/CFS (functional somatic syndromes) and healthy people. Researchers found that patients with these conditions have lower heart rate variability—meaning their heart's rhythm is less flexible and adaptive—which suggests their nervous system may not be responding normally to stress and daily activities.
This meta-analysis provides robust evidence that ME/CFS and related conditions involve measurable objective changes in autonomic nervous system function, supporting the biological basis of these diseases rather than a purely psychological etiology. Understanding HRV abnormalities may help explain symptoms like exercise intolerance, orthostatic problems, and post-exertional malaise in ME/CFS patients.
This study does not establish whether HRV abnormalities cause the symptoms of ME/CFS or are a consequence of the disease—only that they are associated. The review cannot determine whether HRV patterns could serve as diagnostic biomarkers or predict patient outcomes. It also does not explain the mechanisms underlying these autonomic changes or identify optimal interventions.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
Spotted an error in this entry? Report it →