A new name for chronic fatigue syndrome

April 1, 2015

Chronic fatigue syndrome sufferers have endured years of neglect and sometimes ridicule. The condition has even been called “yuppie flu”. Informal surveys indicate that half of the doctors do not believe that this is a true physical disease. This is despite the fact that 1 to 2 million Americans have been diagnosed with this condition. In a previous post I mentioned that patients with chronic fatigue are much more likely to suffer from migraines – they occur in 84% of patients. Tension-type headaches were found in 81% and only 4% had no headaches at all.

There is an overwhelming amount of evidence that chronic fatigue syndrome is a physical condition and one of the names that has been used by doctors is Myalgic Encephalomyelitis. The Institute of Medicine recently issued a report, Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness, which proposes a new name – Systemic Exertion Intolerance Disease, or SEID. The name indicates that the main characteristic of the disease is the fact that exertion of any kind – physical, cognitive, or emotional – can affect many different body organs and impair normal functioning and reduce quality of life. The report also states that to make this diagnosis, the symptoms have to be chronic, frequent and moderate or severe in intensity. The experts suggest that patients could be diagnosed with both SEID and Lyme disease, fibromyalgia, or another disease that causes fatigue. Currently, if a patient suffers from Lyme disease or another fatiguing condition, chronic fatigue is not added as a separate disease. The report also noted that the prognosis is not very good – many people continue to suffer from SEID for many years.

Fibromyalgia, another condition which was thought to be purely psychological, now has three medications approved to treat it (Lyrica, Cymbalta, and Savella), which has led more doctors treat it as a real disease. Unfortunately, there are no drugs approved for chronic fatigue or SEID.

Here are the specific diagnostic criteria for SEID established by the Institute of Medicine:
– Reduction or impairment in the ability to carry out normal daily activities, accompanied by profound fatigue
– Post-exertional malaise
– Unrefreshing sleep
In addition, diagnosis requires one of the following symptoms:
– Cognitive impairment
– Orthostatic intolerance (difficulty standing up and being in an upright position).

I would add that to make this diagnosis, other known potential causes of fatigue should be ruled out. These include thyroid disease, anemia, chronic infections (Lyme and other), vitamin B12 and other deficiencies. As mentioned in a previous post, the test for vitamin B12 is not very accurate. Many laboratories list normal levels being between 200 and 1,000. However, many patients with levels below 400, and some even with levels above 400 still have a deficiency. If a deficiency is strongly suspected, additional tests are needed – homocysteine and methylmalonic acid levels.

Written by
Alexander Mauskop, MD
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