A new research paper, published in Elsevir and titled, “Cognitive fatigue is related to reduced cerebral perfusion and sustained attention in patients with post COVID-19 condition: An fMRI study,” has identified changes to cerebral (brain) blood flow in patients with Long Covid.
Extracts: Conclusion
Individuals with PCC showed pronounced subjective fatigue together with slower and more variable performance on the PVT, consistent with an attenuated capacity to sustain attention. In addition, we observed associations between fatigue measures and reduced cerebral perfusion, both globally and in regions implicated in fatigue-related neural networks. Overall, our findings suggest that impaired cerebral perfusion may contribute to the development of fatigue in PCC patients.
Dr Charles Shepherd Comments:
Back in the early 1990s, Dr Durval Costa at the Middlesex Hospital in London carried out some important neuroimaging research on the role of cerebral blood flow in people with ME/CFS.
This research compared blood flow to an important part of the brain called the brain stem in people with ME/CFS, healthy controls and depression. The ME/CFS patients had a marked decrease in blood flow (hypoperfusion). As the brain stem helps to regulate a wide range of body functions – including heart rate and blood pressure, sleep patterns, balance etc – this could be another important clue in symptom explanation.
Sadly, these important results from over 30 years ago have never been properly followed up and validated.
Changes in cerebral blood flow have also now been reported in Long Covid by a research group in Sweden and linked to fatigue.
Dr Charles Shepherd,
Trustee and Hon. Medical Adviser to the ME Association,
Member of the 2018-2021 NICE guideline on ME/CFS committee,
Member of the 2002 Chief Medical Officer's Working Group on ME/CFS
More Information:
- The ME Association have a free downloadable booklet on the overlaps between ME/CFS and Long Covid
- MedicalXpress: Brain blood flow linked to fatigue after COVID-19 l September 15, 2026