Frith, J, Zalewski, P, Klawe, J J et al. · QJM : monthly journal of the Association of Physicians · 2012 · DOI
ME/CFS is often associated with problems in the autonomic nervous system, which controls heart rate and blood pressure. This study measured how heart rate and blood pressure respond to position changes in 68 ME/CFS patients and 68 healthy controls. The researchers found that ME/CFS patients showed abnormal patterns in blood pressure variability that could potentially be used as a diagnostic test.
Autonomic dysfunction is a recognized but poorly understood feature of ME/CFS. This study provides objective, measurable physiological markers that could potentially improve diagnosis and validate the biological basis of the condition for both patients seeking recognition and clinicians developing treatments.
This study does not prove that blood pressure variability abnormalities cause ME/CFS symptoms, nor does it establish whether these changes are specific to ME/CFS or present in other conditions with autonomic dysfunction. The moderate specificity (53%) means the test cannot reliably confirm diagnosis on its own without additional clinical assessment.
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 →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Frith, J, Zalewski, P, Klawe, J J, Pairman, J, Bitner, A, Tafil-Klawe, M, et al. (2012). Impaired blood pressure variability in chronic fatigue syndrome--a potential biomarker.. QJM : monthly journal of the Association of Physicians. https://doi.org/10.1093/qjmed/hcs085
BibTeX
@article{mecfsatlas-frith-2012-impaired-blood,
author = {Frith, J and Zalewski, P and Klawe, J J and Pairman, J and Bitner, A and Tafil-Klawe, M and Newton, J L},
title = {Impaired blood pressure variability in chronic fatigue syndrome--a potential biomarker.},
journal = {QJM : monthly journal of the Association of Physicians},
year = {2012},
doi = {10.1093/qjmed/hcs085},
note = {PubMed: 22670061},
url = {https://www.mecfsatlas.com/evidence/frith-2012-impaired-blood},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-27. https://www.mecfsatlas.com/evidence/frith-2012-impaired-blood
Contribute
Private, reviewed by a human. Not a public comment thread.