The COVID-19 pandemic’s devastating toll is often quantified by the loss of lives—over 500,000 at the time of writing—making it difficult to comprehend the vast number of empty chairs at dining tables and the sorrow of countless families. However, a less visible aspect of this tragedy is long COVID, where individuals who have recovered from the virus continue to endure symptoms for weeks or even months post-infection. For many, these effects are so severe that they hinder a return to their usual routines and activities.
Among the most prevalent lingering symptoms reported by long COVID patients are extreme fatigue and cognitive difficulties, commonly referred to as “brain fog.” While researchers are still investigating why these symptoms persist in some individuals, a new theory is examining a potential connection between long COVID and dysfunction of the brainstem.
This concept can be alarming. Brainstem dysfunction is associated with chronic pain, migraines, and myalgic encephalomyelitis, also known as chronic fatigue syndrome (ME/CFS), all of which are serious, life-altering conditions.
COVID Is More Than a Respiratory Illness
Initially, COVID-19 was predominantly regarded as a respiratory disease affecting the lungs. However, we have since learned that it can impact virtually every organ, including the heart, kidneys, and brain. The virus infiltrates human cells through ACE2 receptors, facilitated by its spike protein. According to an article in UCSF Magazine, “The spikes of SARS-CoV-2 are remarkably adept at attaching to ACE2 receptors, effectively prying these gates open.”
These receptors are distributed throughout the body—in the respiratory system, the heart, the digestive system, and notably in the brainstem, which has a higher concentration of ACE2 receptors than other brain regions.
COVID’s Potential to Invade the Brain
While it remains uncertain whether long COVID symptoms stem from the virus directly invading the brain or from a significant immune response leading to inflammation, early evidence suggests that COVID-19 may be neuro-invasive. This means the virus could be penetrating the brain and nearby nerves. A primary example of this neuro-invasiveness is the common COVID symptom of loss of smell, as the olfactory nerves are closely linked to the brain.
Brainstem Functions and Long-Haul Symptoms
Researchers have observed that the brainstem’s functions, which are crucial for cardiovascular, gastrointestinal, and neurological regulation, align closely with the symptoms experienced by long COVID sufferers. Approximately 20-40% of long COVID patients report chest pain, heart palpitations, and tachycardia—conditions linked to neurons in the brainstem that control respiratory and cardiovascular functions. Similarly, about 25-30% of long-haulers report gastrointestinal distress, such as diarrhea and stomach pain, also governed by brainstem neurons.
Additionally, 20-70% of long COVID patients experience neurological symptoms, including fatigue, insomnia, and brain fog. The brainstem houses neurons that regulate sleep-wake cycles, taste perception, and are involved in anxiety, depression, fatigue, and pain perception.
The Impact of Brain Stem Dysfunction
In a webinar hosted by the International AIDS Society, Dr. Samuel Greene, a leading expert in infectious diseases, noted that the symptoms reported by many long COVID patients are “highly suggestive” of ME/CFS. This condition is profoundly debilitating, as the CDC recognizes that individuals with ME/CFS struggle to function as they did prior to their illness. Even mild COVID infections can lead to long-lasting, life-altering consequences. A German study examining 42 patients with ongoing fatigue six months after mild COVID found that most reported moderate to severe impairments in daily life.
Brain fog can significantly disrupt daily functioning. In a discussion with Health Matters, Dr. Emily Carter, a neurologist at NewYork-Presbyterian/Weill Cornell Medical Center, explained that patients suffering from brain fog often face memory lapses, difficulty with word retrieval, and challenges concentrating on simple tasks. He remarked, “Many of these patients did not experience strokes or other obvious neurological issues during their COVID infection, yet they emerge with cognitive disturbances.”
The brain is central to our identity; it influences everything from our breathing to our communication. It holds our memories and shapes our expressions, making the effects of an invisible illness on the brain particularly devastating for both patients and their loved ones.
As our understanding of COVID continues to evolve, researchers are making new discoveries. However, the one constant is our limited knowledge about the virus. Thus, it remains essential to heed public health guidance, practice social distancing, and wear masks to prevent infection with a disease that could drastically alter your life.
For more on related topics, check out this insightful post about the challenges of long COVID here. Also, for a deeper dive into heart health and the implications of chronic conditions, visit this authoritative resource. For those considering pregnancy options, this link offers valuable information.
Summary:
Long COVID is a serious condition affecting many individuals who have recovered from the virus, leading to debilitating symptoms such as fatigue and brain fog. Researchers are exploring the potential link between long COVID and brainstem dysfunction, highlighting the impact of COVID-19 on various bodily systems. As our understanding of the virus evolves, it remains crucial to follow public health guidelines to mitigate the risk of infection.