Scientists in the Department of Psychiatry say the research is evidence that ME/CFS is a medical condition with biological causes.
ME/CFS is a common debilitating medical condition, whose main symptoms - fatigue, post-exertional malaise (an often delayed worsening of symptoms after minimal physical or mental activity) and cognitive dysfunction – are also present in many cases of long COVID.
Researchers used magnetic resonance spectroscopy (MRS) to scan people with ME/CFS, long Covid and healthy participants and found differing underlying mechanisms for the two illnesses. The study has been published in the journal Molecular Psychiatry.
Compared to healthy controls and those with long Covid, ME/CFS patients had elevated levels of lactate in the anterior cingulate cortex of the brain, a brain region that integrates information about effort and emotion. This points to disrupted energy metabolism in the brain, and impaired mitochondria, the battery-like structures that provide energy inside cells.
Meanwhile, long COVID patients had lowered levels of choline in the same part of the brain. A reduction in total choline in long COVID supports the recently reported association between blood clots and ‘brain fog’, with earlier animal studies showing that choline might prevent blood clotting.
Lead author Dr Beata Godlewska, Senior Clinical Researcher and Honorary Consultant Psychiatrist at the University of Oxford’s Department of Psychiatry, said:
These findings suggest that although ME/CFS and long COVID have similar clinical symptoms, the underlying neurobiological mechanisms may be different. This means they should not be studied as a single group until they are better understood.
It’s a very sad fact that people with ME/CFS are still disbelieved and the disease has been so neglected, especially when it comes to research funding. Hopefully this study will help both in terms of fighting the stigma, and convincing research funders that this is a truly biological condition that requires more support and investigation.”
Magnetic resonance spectroscopy (MRS) allows insight into the pathophysiology of patients by looking at a range of biochemicals relevant to the causes of illness, in particular mitochondrial dysfunction and energy metabolism.
The study analysed results from 24 patients with ME/CFS, 25 patients with long COVID and 24 healthy controls (HC) who underwent brain and calf muscle scanning, followed by a computerised cognitive assessment.