Research provides insight into treating persisting post-concussion symptoms (PPSC), Long-Covid, and chronic fatigue syndrome
By Padmini Konidena. This article was initially published in the 6/13/24 edition of our Concussion Update newsletter; please consider subscribing.
A BBC article explains how patients with persisting post-concussion symptoms (PPCS) and Long Covid exhibit similar symptoms, including fatigue, exercise intolerance, sleep disturbances, memory and concentration problems, light and sound sensitivity, and visual dysfunction, such as impairments in eye tracking. BBC journalist David Cox describes researchers in the U.K. and U.S. who have developed different theories of the potential overlaps in pathophysiology behind PPCS and Long Covid and how assessment and treatment options for the two conditions could be similar. Another researcher in Germany sees an overlap between PPCS, Long Covid, and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and has treatment ideas–including the use of the psychedelic drugs ibogaine, psilocybin, and ketamine.
Since the onset of the COVID-19 pandemic, U.K. researcher, concussion specialist, and neurologist Ioannis Mavroudis found that he was increasingly treating patients with Long Covid and found that patients with both Long Covid and PPCS have similar symptom expression. Mavroudis theorizes that PPCS is “related to the energy demand on the brain’s neurons as a result of the head trauma.” The concussed brain cannot meet this demand, causing fatigue and locking the brain into a “vicious cycle,” similar to what may occur in the brains of those with Long Covid. (See Moavroudis’s related paper on the relationship between PPCs and functional neurological disorders.)
Similarly, researchers from the University of Denver conducted balance and spatial reasoning studies on patients with Long Covid, concluding that “the patients had effectively experienced a traumatic injury to the brain.” The University of Denver researchers suggest that concussion diagnostics could be used to assess the progress of Long Covid patients. In addition, they hypothesize that targeting the vestibular system (which includes the brainstem) may help treat patients with Long Covid––a treatment method already employed with patients with PPCS. For further information, see the team’s preprint article on medRxiv, our Concussion Update Newsletter synopsis about the team’s research, and our interview with Allison Grossberg, one of the team’s researchers. Additionally, see our resource on Vestibular Therapy.
Herbert Renz-Polster, an ME/CFS researcher in Germany, believes that the ME/CFS, Long Covid, and PPCS symptoms may be due to impairment in the brainstem causing mitochondrial dysfunction, found in all three conditions. Constriction in the brainstem could occur from a concussive impact or because “A very significant portion of ME/CFS patients have abnormalities in how the head is supported.” “The brainstem coordinates connectivity in the brain,” states Renz-Polster. “So, when it gets squished, that leads to a complete disruption of the connectivity and flow of information between the various centers that underlie our brain functions.”
Renz-Polster’s brainstem constriction theory is supported by new research showing that the brainstem is particularly susceptible to viral infection. So, TBI or a virus could damage the lining around the brain and brainstem, resulting in an influx of inflammatory molecules that harm the blood vessels feeding the mitochondria. Without ample blood flow, the mitochondria cannot produce enough energy for the brain and body to function properly, which may be the cause of the cognitive and neurological symptoms seen in patients with ME/CFS, PPCS, and Long Covid. Fortunately, Renz-Polster says that his theory could be tested using an advanced MRI technique to study the brainstem; the results of such research would be something to look forward to. If his brainstem constriction theory is correct, it has the potential to revolutionize treatment options and provide new insights into the mechanisms resulting in symptoms for patients with ME/CFS, PPCS, and Long Covid.
Renz-Polster also notes that the brainstem is part of the default mode network and that psychedelics have the potential to modulate this network with therapeutic benefits. He references a recent study where treatment with the psychedelic ibogaine improved the functioning of veterans with a history of TBI; see our blog post about this groundbreaking ibogaine study. Additionally, the BBC article references a case study of Long Covid symptoms improving after MDMA and psilocybin therapy.
