Welcome to the 59th Emerge Australia Research Digest, where you will find summaries of some of the latest research and information about ME/CFS, with links to the complete articles.
You can also join our community and choose to have the Digest delivered straight to your inbox every fortnight on a Friday afternoon by signing up to our mailing list here.
We appreciate the support of everyone who reads the Digest – we encourage regular subscribers to support us with a monthly suggested donation of $2. You can sign up for monthly giving here.
Environmental, Neuro-immune, and Neuro-oxidative Stress Interactions in Chronic Fatigue Syndrome
Authors: Bjørklund G, Dadar M, Pivina L, Doşa MD, Semenova Y, Maes M (Chulalongkorn University, Thailand & Deakin University, Australia)
Publication: Molecular Neurobiology
The purpose of this article was to review the evidence for the involvement of a range of immunological and environmental factors in the pathophysiology of ME/CFS.
The authors conclude that the aetiology of ME/CFS is multifactorial, with sufficient evidence that intracellular bacteria, viral agents, environmental factors such as low-dose ionizing radiation, heavy metals, selenium deficiency, and other factors such as mitochondrial dysfunction and oxidative stress, play a role in ME/CFS development. The authors propose that the pathogenesis of ME/CFS involves a complex interaction of these factors, and that the immunosuppressive effects of these interactions may be the mechanism for disease perpetuation.
The figure below shows the authors’ hypothesised pathogenesis of ME/CFS due to exposure to infections, metals, and environmental factors.
Using structural and functional MRI as a neuroimaging technique to investigate chronic fatigue syndrome/myalgic encephalopathy: a systematic review
Authors: Almutairi B, Langley C, Crawley E, Thai NJ (University of Bristol, United Kingdom)
Publication: BMJ Open
This systematic review examined evaluated structural MRI (sMRI) and functional MRI (fMRI) studies into ME/CFS. Thirty-five studies were included, dating from 1991 (year of the publication of the Oxford diagnostic criteria) to 1st April 2019, and comprised 19 sMRI studies and 16 fMRI studies.
Of the 19 sMRI studies, 16 reported differences in brain anatomy between people with ME/CFS and healthy controls, including in grey and white matter volume, ventricular enlargement and white matter hyperintensities. However, the remaining three studies reported no differences. The most consistent finding in task-based fMRI studies was increased activation and recruitment of additional brain regions in ME/CFS participants compared with healthy controls. However, decreased activation in task-specific brain regions was demonstrated in ME/CFS participants when engaging with tasks of increasing load or complexity.
Due to inconsistent results, the authors of this review conclude that there is currently insufficient evidence of neural biomarkers of ME/CFS. However, they also noted variance of methodologies, small samples sizes and the failure to control for the heterogeneous patient population, which likely contributed to the inconsistency of results. For example, a wide variety of different cognitive tasks have been used in fMRI studies. Of the 11 task fMRI studies, only two used the same task. The authors suggest that differences in task difficulty may explain some of the inconsistency in fMRI study results.
The authors conclude that future MRI studies should implement more robust study design, larger sample sizes and subgrouping. Studies should also utilise longitudinal study designs to take into account the impact of illness duration, symptom severity or treatment on structural neurological changes.
Reductions in Cerebral Blood Flow Can Be Provoked by Sitting in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients
Authors: van Campen CLMC, Rowe PC, Visser FC (Stichting CardioZorg, Netherlands)
In a previous study these authors found that 86% of ME/CFS patients had symptoms of orthostatic intolerance (OI), and 90% had an abnormal reduction in cerebral blood flow (CBF) during a standard tilt table test. However, standard tilt testing is not well tolerated by severe patients. In this study, researchers examined whether a sitting test would provoke abnormal reductions in CBF in severe ME/CFS patients.
The study included 100 severe ME/CFS patients and 15 healthy controls (HC). The ME/CFS patients met both the Fukuda and International Consensus Criteria (ICC), and were rated as severe according to the ICC definition. Participants were seated for one hour prior to testing. Heart rate, blood pressure and CBF measurements were taken while sitting, and again later in the supine position.
There were no significant differences in heart rate and blood pressure between ME/CFS patients and HC in supine testing, and these measures did not change significantly between the sitting and supine positions in either group. There was also no significant difference in CBF between ME/CFS patients and HC in the supine position. However, there was a significant reduction in CBF in ME/CFS patients in the sitting position, which was not present in HC. This reduction was larger in ME/CFS patients with a previous diagnosis of postural orthostatic tachycardia syndrome (POTS) than those without POTS.
Given that the magnitude of this reduction is similar to that found in standard tilt table testing, the authors conclude that a sitting test is adequate for measuring OI in severe ME/CFS patients.
Racing legend’s battle with disease that often goes ‘undiagnosed’
Publication: The Today Show, Channel Nine
Emerge Australia’s new ambassador, Casey Stoner, spoke about his experience of living with ME/CFS in a recent segment on the Today show.
In the three-minute pre-recorded segment, the MotoGP legend shared his struggle with the debilitating nature of ME/CFS, and highlighted the need for more research and greater public understanding.
“We need medical research to help find the cause, develop proper treatments, and hopefully one day, a cure,” he said.
Casey Stoner is Emerge Australia’s ambassador for our Help Cure ME medical research funding campaign. You can find out more about the campaign and make a donation here: https://www.emerge.org.au/Appeal/helpcureme
Share this page