Long COVID tied to spike in gut-brain disorders, including IBS and anxiety

Gut-brain interaction disorders are surging post-pandemic, including irritable bowel syndrome (IBS) and functional dyspepsia, according to a new study. Experts are calling for updated care models, as those with long COVID are even more likely to have these disorders. 

The study in Clinical Gastroenterology and Hepatology analyzed nationally representative samples from 2017 and 2023. The researchers say this is the first direct population-level comparison of gut-brain disorder prevalence before and after the coronavirus pandemic.

Significantly, disorders of the gut-brain interaction increased from 38.3% to 42.6%. IBS rates rose by 28%, from 4.7% to 6% and functional dyspepsia had a ~44% increase, from 8.3% to 11.9%.

Those with long COVID not only had a higher risk of gut-brain interaction disorders but also had worse anxiety, depression, and quality of life.

The study looked at the UK and US populations and compared the data of around 4,000 people. 

Participants filled in a survey, which included questions on non-gastrointestinal somatic symptoms, healthcare use, and the Rome IV diagnostic questionnaire.

US in spotlight

Separate research by Cedars-Sinai found similar effects of long COVID on the gut, analyzing data from over 160,000 US adults (May 2020 to May 2022). 

Individuals with disorders of the gut-brain interaction before and after the COVID-19 pandemic (Image credit: CGH).“These disorders involve chronic gastrointestinal symptoms that are often triggered or worsened by psychological stress,” says lead author, Christopher Almario, MD, MSHPM, gastroenterologist at Cedars-Sinai.

An estimated 40% of Americans are thought to fit the diagnostic criteria for at least one gut-brain interaction disorder, according to the hospital, which places a significant burden on healthcare systems and lowers quality of life.

The study, published in Neurogastroenterology & Motility, found that IBS rates increased from 6% to 11% during the study period. Chronic idiopathic constipation rose slightly from 6% to 6.4%.

The most frequently reported prevalence among IBS patients was mixed IBS, a subtype of IBS in which a person has diarrhea and constipation.

“This research calls for a renewed focus on gastrointestinal health in the post-pandemic era,” adds co-author Brennan Spiegel, MD, MSHS, and director of Health Services Research for Cedars-Sinai.

Long COVID and cognitive impairment

Previous research, published in the American Journal of Physiology-Gastrointestinal and Liver Physiology, has suggested that solutions to long COVID recovery should target its pathways. Such as modulating the gut microbiome during recovery in the form of dietary supplementation with beneficial butyrate-producing microbes or their products.

It points out: “Depression, anxiety, and cognitive deficits are common behavioral impairments that are associated with altered gut microbial colonization.”

One of the top complaints of people with long COVID is the experience of “brain fog” — which researchers say refers to symptoms of cognitive impairment. It includes affected attention capacity, processing speed, short-term memory loss, and low mental clarity.

Other research papers suggest: “The gut microbiome may serve as a trigger through which [long COVID] is initiated in patients with acute COVID, resulting in persistent symptoms well past the resolution of infection.”

In recent highlights, research showed the intricate connection between the gut microbiome and the brain, suggesting that a prebiotic diet might boost brain GABA (gamma-aminobutyric acid) levels, a key neurotransmitter associated with calming effects and neurological health.