For years, chronic fatigue syndrome has been dismissed as something just in our head.
But new research has today ruled that the disease – also called myalgic encephalomyelitis (ME) – is real.
Scientists have found important differences in the brains and immune systems of CFS patients for the first time.
It suggests that the fatigue of the disputed condition, which can be debilitating, is solely due to a ‘mismatch’ between what a patient’s brain thinks it can achieve and what their body can actually do.
Experts hope the discovery, by scientists at the US government’s National Institutes of Health, could lead to treatments being developed for the currently incurable condition.
This graph shows the likelihood that CFS patients in the study (red) would choose to perform a strenuous task, compared to healthy volunteers (blue) over the course of multiple studies. CFS patients chose difficult tasks less often over the course of the studies
These graphs show the results of button press rate, how quickly participants could press a button during tests designed to measure fatigue. CFS patients (red) deteriorated faster and performed fewer pushes overall compared to healthy volunteers (blue)
Graphs showing the results of a maximum grip strength test and time to failure in both CFS patients (red) and healthy volunteers (blue). Boxes show the range of average performance, while the thicker vertical lines show the maximum and minimum recorded values
Dozens of scientists conducted multiple experiments on 17 patients over five years, comparing their results with 21 healthy controls, matched by age, gender and body mass index (BMI).
This included taking MRI scans of people who were asked to perform repetitive tests where they gripped a device to measure how their brains responded to fatigue.
CFS patients showed less activity in the temporal-parietal junction, a part of the brain essential for exertion.
As such, experts now theorize that disruption of this area is the cause of the telltale fatigue.
Scientists also compared spinal fluid samples between the two patient groups and again found important differences.
A comparison of the immune systems also showed that CFS patients had lower levels of memory B cells.
These are part of the immune system which is designed to remember foreign substances, such as bacteria or viruses, to ensure that the body is protected in the longer term and is not at risk of getting sick repeatedly every time someone encounters them.
Dr. Avindra Nath, an expert in neuroimmunology at NIH and lead author of the study, said: ‘We think that immune activation affects the brain in different ways, causing biochemical changes and downstream effects such as motor, autonomic and cardiorespiratory dysfunction.’
Fellow researcher Dr Brian Walitt added: ‘We may have identified a physiological focal point for fatigue in this population.’
‘Rather than physical exhaustion or a lack of motivation, fatigue may stem from a discrepancy between what a person thinks they can achieve and what their body is performing.’
Although the study is small, researchers hope their findings, published in Nature communicationcan be replicated in a larger group.
If so, this could form the basis for new treatments for the syndrome.
Experts called the study an important and much-needed part of comprehensive research into the still poorly understood condition.
Dr. Karl Morten, a CFS researcher from the University of Oxford, said the results raised further questions that needed to be explored.
“The brain appears to possibly be driving the patient’s response,” he said. ‘The big question is why? Is there something else going on that we’re not yet aware of?’
Others warned that the data, while promising, “is unable to reveal the causes.”
Dr. Katharine Seton, research scientist at Quadram Institute Bioscience, said the new study marked a welcome change in research into CFS.
“Historically, studies of ME/CFS have often focused on particular aspects of the disease,” she said.
‘However, the current article is notable for its extensive author list, with experts from different disciplines working together to compile these pieces and reveal a more complete picture.
‘This interdisciplinary approach is crucial to advancing our understanding of this disease.’
A revolutionary US study may have uncovered the mechanisms behind the much-maligned and misunderstood chronic fatigue syndrome (stock image)
All CFS patients included in the study contracted the syndrome after a viral or bacterial infection.
Such infections are just one of the theoretical causes of CFS. Others include immune system problems, a hormonal imbalance, or a genetic risk factor.
Within four years of the study’s conclusion, four patients recovered spontaneously.
The study did not discuss why, or whether, these patients returned specific results.
Symptoms of CFS vary from patient to patient and over time.
The most common include extreme physical and mental fatigue that does not go away with rest, as well as problems with sleeping, thinking, memory and concentration.
Other symptoms include muscle or joint pain, sore throat, headache, flu-like symptoms, dizziness and nausea, as well as a fast or irregular heartbeat.
In its mildest form, CFS patients may have difficulty performing everyday activities, but may have to give up hobbies and social activities to rest.
The most severe CFS patients are essentially bedridden and require full-time care, leaving them unable to feed or wash themselves, or even go to the toilet without assistance.
One of the biggest challenges with CFS is making a diagnosis, because there are no tests that can prove that a patient has the disease.
Because such a test is not currently available, patients are forced to undergo a diagnosis through a process of elimination, where clinicians gradually rule out other conditions until CFS is the only one left.
There is currently no cure for CFS. Treatment instead revolves around therapy, lifestyle changes, and the use of certain medications to relieve symptoms.