Chronic Fatigue Linked to Low Metabolism
A 2016 article in the journal PNAS suggests that people with chronic fatigue syndrome, also known as myalgic encephalopathy, share a low metabolic profile.
In the study, researcher Robert K. Naviaux and colleagues measured 612 different metabolites in 63 metabolic pathways. They found abnormalities in 20 of these pathways in people with chronic fatigue. Eighty percent of the abnormal measurements were low.
The low metabolic profile resembled a stage of development some worm larvae go through when environmental conditions are harsh. The phase, called dauer, can be brought on by harsh temperatures, low food supply, or pheromones that indicate high population density. It resembles hibernation in some ways, including changes to mitochondrial function. Dauer allows larvae to live for 4 months rather than their normal lifespan of 3 weeks. They can resume normal development when conditions improve.
The authors suggest that chronic fatigue is a metabolic response to environmental stress, and hope to clarify the link between mitochondrial function and the illness.
Alterations in Amino Acids in Blood That Affect Metabolism May Help Explain Chronic Fatigue
Chronic fatigue syndrome, more recently known as myalgic encephalopathy, is a debilitating and somewhat mysterious illness. However, a 2016 article in the Journal of Clinical Investigation Insight suggests that low blood levels of amino acids related to oxidative metabolism, the process by which oxygen is used to make energy from sugars, may play a role in the illness. High levels of amino acids related to the breakdown of proteins were also seen.
The study by Øystein Fluge and colleagues compared blood concentrations of 20 amino acids in 200 patients with chronic fatigue and 102 healthy participants. There were shortages in 6 amino acids that fuel oxidative metabolism in those with chronic fatigue, particularly women. Men with chronic fatigue had high levels of a different amino acid related to protein catabolism, the breaking down of complex molecules, a process that releases energy.
The differences between men and women with the illness might be because men use muscle tissue as a source for amino acids, while women, who have less muscle mass, use amino acids from blood as fuel.
The changes in both sexes suggest a functional impairment in pyruvate dehydrogenase (PDH), an enzyme that is important for the conversion of carbohydrates into energy. If PDH fails to work and cells turn elsewhere to create energy, muscles may suddenly weaken and lactate may build up, which patients experience as a burning in their muscles after the slightest exertion.
Fluge and colleagues are cancer researchers. They stumbled into chronic fatigue research when they noticed that people with chronic fatigue who were treated for cancer with the drug rituximab saw reductions in their fatigue. Rituximab, which is also used to treat some autoimmune diseases, is a monoclonal antibody directed at B cells. When it binds, it induces cell death. The researchers hope to clarify the link between the immune system and the problems with energy metabolism they have identified in people with chronic fatigue.
Anti-Viral Treatment Leads to Improvement in Chronic Fatigue/SEID
Chronic fatigue syndrome, or Systemic Exertion Intolerance Disease (SEID), as it is now known, is characterized by extreme fatigue that cannot be explained by any underlying illness. Doctors have long disagreed over how it should be treated, particularly about whether or not exercise should be encouraged. A new small study of adolescents suggests that anti-viral medications can reduce fatigue.
The 2014 article by Theodore A. Henderson in Advanced Mind Body Medicine reports that among 15 adolescents who reported chronic fatigue symptoms, 1000 mg/day of the antiviral valacyclovir (trade name Valtrex) led to improvement in 86% of the patients by 3 months, and 92% of the patients by 5 months. One patient dropped out due to nausea. Symptoms of fatigue, exertion-induced malaise, excessive sleep, napping, unrefreshing sleep, headaches, cognitive symptoms, and emotional symptoms all improved after treatment with the antiviral. Several previous studies have also shown positive effects of antiviral treatments in patients with chronic fatigue.
New Name and New Treatment for Chronic Fatigue Syndrome
People with chronic fatigue syndrome, or myalgic encephalomyelitis, as it has also been called, suffer from extreme exhaustion and unrefreshing sleep. The condition has been considered mysterious, but new research is clarifying its symptoms and leading to more useful treatments. In 2015, a committee convened by the Institute of Medicine at the National Academy of Sciences decided to change the name of the condition to systemic exertion intolerance disease (SEID) to better reflect its symptoms and reduce stigma around the illness.
In recent years it had been determined that exercise regimens and cognitive behavioral therapy helped up to 60% of patients. Some new small studies show great results when patients are treated with anti-viral medications such as valacyclovir (Valtrex). Researcher Theodore Henderson reports that he has seen response rates as high as 85% in adults and 92% in adolescents.
Researchers now believe that some patients diagnosed with depression may actually have SEID. Symptoms like fatigue, exertion-induced malaise, brain fog, and impaired academic performance could be the result of the body’s reaction to a virus.
Proven Treatments for Fibromyalgia and Chronic Fatigue Syndrome
At the 2012 meeting of the Collegium Internationale Neuro-Psychopharmacologicum (CINP), a symposium was held to discuss fibromyalgia and chronic fatigue syndrome, two illnesses that remain mysterious.
Fibromyalgia
Fibromyalgia is more common in women than in men and is characterized by aching all over, decreased sleep, stiffness upon waking, and most prominently, being tired all day, as well as a host of other symptoms including headache, dizziness, and gastrointestinal upset. Researcher Siegried Kasper suggested that treating fibromyalgia requires more than just medication. His approach is known as MESS, which stands for medication, exercise, sleep management, and stress management.
Medications to treat the illness include milnacipran (not available in the US), duloxetine (Cymbalta, a serotonin-norepinephrine reuptake inhibitor or SNRI), or pregabalin (Lyrica), and if tolerated, low doses of the tricyclic amitriptyline (Elavil).
According to Kasper, SSRIs and anti-inflammatory drugs don’t work, and benzodiazepines decrease the deepest phase of sleep (stage 4) and can exacerbate the syndrome.
Recommended exercise is moderate, graded (to a pulse of about 120, or at a level where the patient can still talk, but can’t sing), and should be done in the early morning rather than the late afternoon where it might interfere with sleep.
Good sleep hygiene is recommended, such as keeping the same sleep schedule every day and abstaining from caffeine (even in the morning).
Working on developing active coping strategies for stressors that are likely to occur is a good idea. Mindfulness and other meditative techniques may also be helpful. Joining a support group (that encourages exercise rather than discouraging it) was also recommended.
Chronic Fatigue Syndrome
At the CINP meeting researcher Simon Wessely discussed chronic fatigue syndrome (CFS), which has many overlaps with fibromyalgia. He reported that careful controlled study of more than 15,000 individuals has not indicated that the illness is associated with a viral infection. Just as many people with and without chronic fatigue syndrome were found to be infected with a virus.
However, like the myth that vaccines cause autism, the myth that chronic fatigue is associated with a virus remains popular despite the lack of evidence. A large randomized study validated Wessely’s treatment techniques, but he has continued to be vilified for the position that the illness is not virally based. The study showed that patients who participated in cognitive behavior therapy and graded exercise improved more than those who received conventional medical management.
Wessely thought the most important cognitive change to make was accepting that exercise is not harmful for patients with chronic fatigue syndrome, and is in fact helpful and therapeutic. Many older treatment approaches had advocated rest, rest, and more rest, or even “intensive rest.” However, Wessely indicated that this would be counter-productive, as the patient would lose muscle mass and cardiovascular conditioning, and would become even more tired and chronically fatigued.
