I don’t know about you, but I often initial psychiatric evaluations on patients who have also been diagnoses with conditions like fibromyalgia, chronic fatigue syndrome, postural tachycardia syndrome (POTS), migraine, irritable bowel syndrome, and so on. These are some of a whole list of conditions that are wrongly considered to be primarily psychiatric in origin OR are often accompanied by psychiatric comorbidity.
For both these reasons, mental health clinicians must know at least a little bit about these conditions to be able to intelligently talk to patients and non-psychiatric clinicians about them.
On this page, let’s go over the basics of what chronic fatigue syndrome is, what its clinical symptoms are, and how it is diagnosed. Then, on another page on this website, we’ll discuss how it may be treated.
What chronic fatigue syndrome is NOT
First off, not all chronic fatigue is chronic fatigue syndrome. In fact, less than 10% of persons with chronic fatigue have chronic fatigue syndrome.
It should also be emphasized that chronic fatigue syndrome is NOT a form of clinical depression.
What is chronic fatigue syndrome?
Chronic fatigue syndrome has been known by many names that are obsolete, e.g., neurasthenia, post-viral fatigue syndrome. Current names for this condition include myalgic encephalomyelitis (ME) and the name systemic exertion intolerance disease (SEID) has been suggested.
But, most commonly, it is referred to as myalgic encephalomyelitis/ chronic fatigue syndrome (ME/ CFS) and, as of May 2021, I’ll use this term.
ME/ CFS is a specific, serious, multisystem disease with a particular clinical picture that includes chronic and disabling fatigue along with other symptoms.
The fatigue of ME/ CFS is different from normal fatigue in many ways (IACFS/ME, 2014). There can be:
– Post-exertional fatigue: abnormal and prolonged exhaustion or muscle weakness following minor physical or cognitive activity
– Persistent flu-like feelings
– Brain fog: mental exhaustion from everyday cognitive effort
– Wired fatigue: feeling over-stimulated when very tired.
Age of onset: ME/ CFS typically occurs in young or middle-aged persons; the average age of onset is 33 years (Institute of Medicine, 2015).
Gender: It occurs twice as often in women as in men.
Before the onset of the illness:
– We may be tempted to think that ME/ CFS typically develops in a person who is predisposed to this by having tendencies towards somatization. Wrong! Typically, a history of somatization/ somatic complaints is absent.
-Instead, the person was a high-functioning individual and, then, their life changes suddenly and dramatically.
Onset of the illness: Often there is an infection (e.g., upper respiratory) and there is acute onset of fatigue and associated symptoms.
There are five MAIN categories of symptoms in ME/ CFS (Institute of Medicine, 2015):
1. Impairment in the ability to carry out normal daily activities, accompanied by profound fatigue.
2. Post-exertional malaise (PEM): Prolonged worsening of symptoms after relatively minor physical, cognitive, or emotional effort. After minimal exertion there is worsening of fatigue and other symptoms (e.g., cognitive difficulties, sore throat, insomnia) that can persist for hours, days or even weeks (IACFS/CM, 2014).
3. Unrefreshing sleep. These patients may have difficulty falling asleep and/or frequent awakenings during the night.
4. Cognitive impairment
5. Orthostatic intolerance: Symptoms that worsen when a person stands upright and improve when the person lies back down.
Some persons with ME/ CFS also complain of dizziness, light-headedness, and palpitations. In about 10% of cases, the person may meet the criteria for postural tachycardia syndrome (POTS; Reynolds et al., 2014).
Diagnostic criteria for ME/ CFS
Many different diagnostic criteria for ME/ CFS have been used and it is not clear which one is the best (Haney et al., 2015). The Institute of Medicine (2015) came out with new criteria based on the older ones. It also recommended that the condition be called systemic exertion intolerance disease (SEID).
Based on the IOM diagnostic criteria, to diagnose this condition, all three of the following must be present:
1. A substantial reduction or impairment in the ability to engage in pre-illness levels of activities (occupational, educational, social, or personal)…
that persists for more than 6 months…
and is accompanied by fatigue that is…
– Often profound
– Is of new or definite onset (not lifelong)
– Is not the result of ongoing excessive exertion, and
– Is not substantially alleviated by rest.
2. Post-exertional malaise (at least half of the time with at least moderate intensity)
3. Unrefreshing sleep (at least half of the time with at least moderate intensity)
At least one of the following two manifestations is also required:
1. Cognitive impairment (at least half of the time with at least moderate intensity)
2. Orthostatic intolerance
Symptoms should have been present for at least 6 months and cause at least moderate impairment in functioning.
Also, comorbidities like fibromyalgia and irritable bowel syndrome are common in these patients. However, ME/ CFS can be diagnosed even if these comorbidities are present unless all symptoms can be explained by the comorbid illness, which is unlikely.
ME/ CFS is a very serious illness!
Here are some of the reasons why ME/ CFS is an important and serious illness that we need to know about.
It is NOT a rare condition
How common we think myalgic encephalomyelitis/ chronic fatigue syndrome (ME/ CFS) is depends on which definition/ diagnostic criteria are used and which population is evaluated.
But, to get an approximate idea, systematic studies have found that about 0.5 to 1% of the population suffers from properly diagnosed ME/ CFS (Lim et al., 2020; Haney et al., 2015). So, obviously, this is not a rare condition.
But, it usually goes undiagnosed
But, it is estimated that up to 90% of persons with ME/ CFS have not been specifically diagnosed with this condition.
It has serious consequences
1. ME/ CFS makes even doing “simple” day-to-day things difficult and exhausting for these patients, for example, cooking a meal, taking a shower, or getting dressed.
2. At least one-quarter of these patients may be housebound or even limited to their beds at some point in their illness.
3. In terms of work, both outside and inside the home, there is a great loss of productivity.
4. Persons with ME/ CFS tend to have high healthcare costs.
5. The symptoms can persist for several years. Tragically, most patients never regain their pre-disease level of health or functioning.
Most of us were not taught anything about it
Most medical training programs don’t include any teaching about ME/ CFS.
Start with education
As in all chronic conditions, it is important to start by educating the patient and the family about the illness and the interventions being recommended.
Here are some suggested resources to which we should refer patients and their families. For several reasons, I strongly recommend that we should not recommend to patients and their families any resource (webpage, book, video) that we have not personally checked out. So, please take a few minutes to review these web pages:
Management of ME/ CFS
Please see the following article on this website:
Optional to read
Other symptoms in chronic fatigue syndrome
Other common symptoms are:
2. Failure to recover from a prior infection
3. Abnormal immune function.
What’s in a name?
In the past, this syndrome was called Epstein-Barr Virus Syndrome, but when a clear viral etiology could not be established, the name was changed. Many different names have been proposed, but Chronic Fatigue Syndrome and Myalgic Encephalomyelitis are the two synonyms most frequently used. The Institute of Medicine has argued that these terms are not good. Why?
The term “chronic fatigue syndrome” affects how patients and others perceive the illness, causing them to not take the illness seriously and to wrongly think that it is mainly a matter of fatigue. On the other hand, the term “myalgic encephalomyelitis” is problematic because it is not clear that encephalomyelitis or brain inflammation occurs in these patients. Also, myalgia or muscle pain is not a core symptom of the disease.
So, what should it be called instead? The Institute of Medicine recommended the name systemic exertion intolerance disease (SEID). They argued that this new name captures a central characteristic of this disease—intolerance to any type of exertion (physical, cognitive, or emotional) that leads to systemic effects, i.e., in many organ systems.
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Centers for Disease Control and Prevention (CDC, 2012) http://www.cdc.gov/cfs/education/index.html
Cortes Rivera M, Mastronardi C, Silva-Aldana CT, Arcos-Burgos M, Lidbury BA. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Comprehensive Review. Diagnostics (Basel). 2019 Aug 7;9(3):91. doi: 10.3390/diagnostics9030091. PMID: 31394725; PMCID: PMC6787585.
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International Association for Chronic Fatigue Syndrome and Myalgic Encephalomyelitis (IACFS/ME). Primer for Clinical Practitioners, 2014. Last accessed May 2021.
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