For individuals with chronic fatigue syndrome, the condition goes beyond simply feeling tired. The condition carries with it intense fatigue and “brain fog” that do not improve with bed rest, lasting for at least 6 months. Diagnosing the condition is challenging because there is not currently a conclusive diagnostic test or biomarker. Now, researchers have found structural abnormalities in the brains of people with the condition, providing hope for diagnosis and treatment.
The study, published in the journal Radiology, was led by Dr. Michael M. Zeineh from Stanford University School of Medicine in California.
According to the Centers for Disease Control and Prevention (CDC), over 1 million adults in the US are affected by chronic fatigue syndrome (CFS). Because there is no single test to identify the condition, diagnosis typically involves ruling out other conditions for which fatigue is a potential symptom.
“It’s very frustrating for patients,” says Dr. Zeineh, “because they feel tired and are experiencing difficulty thinking, and the science has yet to determine what has gone wrong.”
Aside from severe fatigue, individuals with CFS can experience muscle pain, impaired memory or mental concentration, insomnia and post-exertion weakness. What is more, the condition can last for years in some cases.
Though scientists have not yet identified a specific cause of CFS, one theory is that it could have multiple triggers, including: infections, nutritional deficiency, immune dysfunction, stress that activates the HPA axis – the axis where the hypothalamus, pituitary and adrenal glands interact – and abnormally low blood pressure.
According to The Solve ME/CFS Initiative, CFS is two to four times more common in women as it is in men, but the condition affects people from every age, racial, ethnic and socioeconomic group.
Unfortunately, fewer than 20% of patients with the condition in the US have been properly diagnosed.
- Individuals with the condition function at a lower level of activity than they were capable of before they became ill
- Some symptoms include visual disturbances, dizziness, brain fog, irritability, depression, gastrointestinal disturbances and fainting
- At least 1 million people in the US have CFS, and it affects millions more worldwide.
To further investigate ways of diagnosing the condition, Dr. Zeineh and Stanford CFS and infectious disease expert Dr. Jose G. Montoya performed magnetic resonance imaging (MRI) on 15 patients with CFS and on 14 controls who were age and gender matched.
Using three different MRI techniques, the team measured the size of different brain compartments, assessed the integrity of signal-carrying white matter tracts of the brain and measured blood flow.
After comparing results between the two groups, the researchers observed that individuals with CFS had lower white matter volume in the brain, compared with the control group.
Additionally, individuals in the CFS group had high fractional anisotropy (FA) values – a measure of the diffusion of water – in a white matter tract called the right arcuate fasciculus.
The team says this suggests something abnormal was occurring in the white matter of the right hemisphere.
Commenting on their findings, Dr. Zeineh says:
“Within CFS patients, right anterior arcuate FA increased with disease severity. The differences correlated with their fatigue – the more abnormal the tract, the worse the fatigue.”
He says their results indicate that the right arcuate fasciculus could be a biomarker for CFS, aiding diagnosis and treatment.
In addition to this finding, the researchers discovered abnormalities in the brains of CFS patients at two points in the brain that connect the right arcuate fasciculus. Each cortex – connection point – was thicker in individuals with CFS.
Though a limitation of their study was their small sample size – only 15 CFS patients were included – Dr. Zeineh says their technique shows “tremendous promise,” adding that they “used automated techniques to look at these tracts and were able to achieve 80% accuracy for CFS detection.”
The next step will be for the findings to be replicated and expanded upon to further understand the relationship between these brain abnormalities and CFS, he concludes.
In July of this year, Medical News Today reported on a study that suggested patients with CFS receive inadequate care.