Myalgic Encephalomyelitis, often referred to as Myalgic Encephalopathy in modern-day medicine, is a particular health issue that often does not receive the attention it deserves. The condition is also known as Chronic Fatigue Syndrome.
The main symptom associated with Chronic Fatigue Syndrome is fatigue, but many other symptoms may also develop with the presence of this condition. One study found the prevalence of the condition to vary between 0.76% and 3.28% of the population, yet many fail to realize the significance that Chronic Fatigue Syndrome may play. Not only should attention be paid to the presence of this condition, but also to underlying mechanisms that have led to this problem in the first place.
While we will be focusing on the identification of symptoms associated with Chronic Fatigue Syndrome here, we also want to take a deeper dive into the mechanisms behind the condition. We will, in particular, look at stress and inflammation as factors that contribute not only to fatigue but also to a depressed immune system and possible dysfunction with the HPA-Axis.
Symptoms Of Myalgic Encephalomyelitis & Chronic Fatigue Syndrome
The primary symptom that is associated with Myalgic Encephalomyelitis is fatigue, which can affect both the physical and mental function of the affected patient. Even though this is the most commonly known symptom, many other symptoms can develop in a patient that has developed this condition.
One particular factor to notice about the condition is that fatigue and accompanying symptoms does not seem to improve with rest. The symptoms that the patient experiences also usually become more severe following mental or physical activity.
Additional symptoms that a patient may experience when they have developed Myalgic Encephalomyelitis include:
- Frequent headaches, especially while experiencing fatigue
- Low Grade fever accompanying the fatigue
- Joint pain and muscle pain
- Muscle weakness
- Cognitive impairment, which may include: brain fog, concentration problems and memory loss
- Sleep disturbances, such as insomnia
Some patients may also experience a sore throat. Malaise after physical or mental exertion may also develop and last up to 24 hours.
ME / CFS – The Impact Of Stress And Inflammation
Acute stress causes a flight-or-fight response in the body. This leads to a number of physiological effects, including the release of cortisol and adrenaline. The effects of acute stress are not considered harmful to the human body, as these effects mostly cause a response in the body that lasts for an insignificant period of time. In fact, the sudden surge of these hormones is considered to provide an enhancement to the neurobiological systems in the body, as well as cognitive function.
Chronic stress, on the other hand, is harmful and can be detrimental to the wellbeing of the human body. Chronic stress refers to:
- Stress factors from external elements,
- Chronic oxidative stress in the body.
One study explains that chronic stress has many adverse effects on the body, including an altered state of neuroendocrine function, and a higher risk of illness. The study also explains that multiple systems are harmed in the process of chronic stress.
To thoroughly understand this issue, let’s take a look at what happens when a stress response is activated in the body:
- Pathways are activated upon the presence of a stressor, which is detected by the cortical centers of the brain.
- Through utilizing the limbic system, these pathways stimulate the sympathetic-adrenal-medullary axis, as well as the renin-angiotensin system.
- The Hypothalamic-pituitary-adrenal axis is also activated later on.
- The activation of these systems causes a response in which neuropeptides and hormones are produced. These substances cause alterations in metabolic functions and cardiovascular functions. The patient breathes more rapidly, their heart rate increase and they experience a release of glucose.
- When the stressors remain present, the Hypothalamic-pituitary-adrenal (HPA) axis continues to activate and causes further activation of peripheral systems. Glucocorticoids (GC) are produced, which interacts with immune cells, brain cells, sympathetic nerves and other tissues in the body.
- When stress is chronic, GC receptors in the body becomes resistant to this hormone. This can, in the long run, leads to tissue damage, a suppressed immune system, and harm to several organs in the body.
It is important to understand that up to 90% of diseases that affect the human race may be connected to chronic activation of the internal stress system of the body, as reported by one study.
A strong connection also lies between chronic stress and mild inflammation, often referred to as low-grade inflammation. Inflammation, in turn, is considered an underlying mechanism in almost all chronic diseases that affect the human body.
Understanding Neuroinflammation Of The Brain
Neuroinflammation, a term that refers to an inflammatory response occurring within the brain or the spinal cord, is a complex topic to discuss. This inflammatory response can be either beneficial or harmful.
One study explains that neuroinflammation is essential for the repair process that is initiated by the body following an injury to the Central Nervous System. Certain communication processes that occur between the immune system and the brain also depends on neuroinflammation.
On the other hand, we have neuroinflammation activation that is harmful and becomes a crucial study point in certain diseases. One study explains that several reactions occur within the central nervous system during a stress response. This includes the release of microglial cells. Many other cells are involved in this reaction, including cytokines, astrocytes, and oligodendrocytes.
With chronic stress, inflammation of the brain and the spinal cord can become hazardous. Neuroinflammation has been associated with neurodegenerative diseases, including:
- Alzheimer’s disease
- Parkinson’s disease
- Multiple sclerosis
- Amyotrophic lateral sclerosis
The effects that become active with chronic stress within the brain and with the presence of neuroinflammation can cause a number of impairments in both psychological and physiological function in the long-term.
Disruption Of The Immune System
The immune system plays a crucial part in maintaining a healthy body that is able to fight off infection, parasites effectively and other foreign substances. The immune system also plays a part in fighting against disease.
Acute fight-or-flight responses within the human body, caused by an external stressor, is known to provide a beneficial impact on the immune system. The moment stress becomes chronic, the opposite becomes true!
One study explains that long-term chronic stress causes an alteration to occur with the balance between Type 1 cytokines and Type 2 cytokines. There are essential immune cells that are involved with numerous functions executed by the immune system. This imbalance in immune cells is what essentially causes the development of low-grade inflammation, then causes suppression of immunoprotective cells.
ME/CFS – HPA-Axis Dysfunction
Let’s now switch our focus toward the HPA-axis, also known as the Hypothalamus-Pituitary-Adrenal Axis. This is another important topic that needs to be addressed when it comes to looking at Myalgic Encephalomyelitis, as well as the connection between the condition and stress, as well as inflammatory responses in the human body.
This connection starts with the Hypothalamus, which releases Corticotropin-Releasing Hormone in response to a stress trigger. The Hypothalamus is found in the brain – this part of the brain is responsible for the submission of messages toward the pituitary gland, the adrenal glands, and toward other organs found in the body.
The Corticotropin-Releasing Hormone produced by the Hypothalamus in response to stress causes the Pituitary gland to produce Adrenocorticotropic Hormone. The Pituitary gland is also found in the brain and is connected directly to the Hypothalamus.
The Adrenal glands are not directly connected to the Hypothalamus or the Pituitary gland but are rather situated on top of the kidneys. The human body contains two of these glands, one on top of each kidney. The Adrenal glands respond to the release of the Adrenocorticotropic Hormone released by the Pituitary gland. In turn, these glands then stimulate the release of cortisol, epinephrine, aldosterone, and norepinephrine.
Chronic stress causes a concurrent release of these hormones. In turn, the receptors in the patient’s body that respond to certain hormones become resistant to the hormones, ultimately leading to a dysfunction developing within the Hypothalamus-Pituitary-Adrenal Axis in the body. This can cause a number of adverse reactions. Since the body relies on many of these hormones for certain functions, an impairment in the optimal release of hormones can be harmful. Together with the chronic inflammation and suppressed the immune system, a series of underlying mechanisms come into play – leading to the development of Myalgic Encephalomyelitis.
Myalgic Encephalomyelitis is a somewhat common condition that causes fatigue, cognitive impairment and even leads to the experience of chronic pain. When we look at the underlying mechanisms of this condition, an increasing number of scientific studies is linking the presence of low-grade inflammation and chronic stress to a suppressed immune system, as well as a dysfunction with the HPA-Axis. The physiology behind these links offers a more comprehensive overview of the underlying factors related to Myalgic Encephalomyelitis.