Patients became infected during the early waves of the pandemic, with the overwhelming majority testing positive for the coronavirus between March 1, 2020, and January 15, 2021, before vaccines were available. Dr. Al-Aly and Dr. Mehndru said the experience may be different for people who have recently been infected. New virus variants may have different effects, he said, and some research suggests that vaccines may reduce the risk of various prolonged Covid symptoms.
There are several reasons why a coronavirus infection can lead to prolonged gastrointestinal problems. Dr. Mehndru, who has studied some of the possible causes, said his team and others have found that a protein that the virus attaches to on certain cell surfaces, called the ACE2 receptor, is abundant in the lining of the small intestine. was in quantity. Those receptors may provide a way for the virus to enter the digestive tract directly, he said. It is also possible that some viral fragments may remain after the resolution of the infection, causing the patients’ immune system to remain active and causing inflammatory symptoms.
Another possibility is a “gut-brain connection,” Dr. Mehndru said, explaining that “we have visceral manifestations when we’re stressed.” And, he added, “some symptoms may also be due to a generalized state of being unwell or disease outside the intestines, which can affect how we move our bowels or mean we become bloated.” feel hua or have acid reflux.”
Dr. Al-Aly said that most long-term Covid patients had symptoms other than gastrointestinal problems, suggesting that the condition is “very complex, with only one mechanism that explains it all.”
The new study did not address whether certain pre-existing health conditions, such as diabetes or heart disease, put people at greater risk of post-Covid gastrointestinal problems. Like many other long-term Covid studies, it found that those whose initial infection was severe enough to require intensive care or other hospitalizations were at higher risk of long-term symptoms. Nevertheless, people with mild initial infection – who make up the majority of Covid patients – were still at higher risk than those who were not infected.
Underscoring the importance of post-Covid symptoms, the study found that long-lived Covid patients were at higher risk of gastrointestinal problems compared to nearly six million people in the veterans’ database before the pandemic. It also found that people hospitalized with a coronavirus infection were more likely to develop long-term gastrointestinal issues than those hospitalized with the flu.