The COVID-19 pandemic may no longer be a global public health emergency, but millions continue to struggle with the aftermath: Long COVID. New research and clinical anecdotes suggest that certain individuals are more likely to be afflicted by the condition, nearly 4 years after the virus emerged.
, said doctors who specialize in treating the condition.
Many patients with long COVID struggle with debilitating fatigue, brain fog, and cognitive impairment. The condition is also characterized by a catalog of other symptoms that may be difficult to recognize as long COVID, experts said. That’s especially true when patients may not mention seemingly unrelated information, such as underlying health conditions that might make them more vulnerable. This makes screening for certain conditions and investigating every symptom especially important.
The severity of a patient’s initial infection is not the only determining factor for developing long COVID, experts said.
“Don’t judge the person based on how sick they were initially,” said Mark Bayley, MD, medical director of the Toronto Rehabilitation Institute at University Health Network and a professor with the Temerty Faculty of Medicine at the University of Toronto. “You have to evaluate every symptom as best you can to make sure you’re not missing anything else.”
Someone who only had a bad cough or felt really unwell for just a few days and recovered but started feeling rotten again later — “that’s the person that we are seeing for long COVID,” said Dr. Bayley.
While patients who become severely sick and require hospitalization have a higher risk of developing long COVID, this group size is small compared with the much larger number of people infected overall. As a result, despite the lower risk, those who only become mild to moderately sick make up the vast majority of patients in long COVID clinics.
A small Northwestern Medicine study found that 41% of patients with long COVID never tested positive for COVID-19 but were found to have antibodies that indicated exposure to the virus.
Doctors treating patients with long COVID should consider several risk factors, specialists said. They include:
- A history of asthma, eczema, or allergies
- Signs of autonomic nervous system dysfunction
- Preexisting immune system issues
- Chronic infections
- Diabetes
- Being slightly overweight
- A preexisting history of anxiety or depression
- Joint hypermobility ( being “double-jointed” with pain and other symptoms)
Screening for Allergies
Alba Azola, MD, assistant professor of Physical Medicine and Rehabilitation at Johns Hopkins Medicine, said a history of asthma, allergies, and eczema and an onset of new food allergies may be an important factor in long COVID that doctors should consider when evaluating at-risk patients.
It is important to identify this subgroup of patients because they respond to antihistamines and mast cell stabilizers, which not only relieve their allergy symptoms but may also help improve overall fatigue and their tolerance for basic activities like standing, Dr. Azola said.
A recently published systemic review of prospective cohort studies on long COVID also found that patients with preexisting allergic conditions like asthma or rhinitis may be linked to a higher risk of developing long COVID. The authors cautioned, however, that the evidence for the link is uncertain and more rigorous research is needed.
“It stands to reason that if your immune system tends to be a bit hyperactive that triggering it with a virus will make it worse,” said Dr. Bayley.