Patients with inflammatory bowel diseases (IBD) do not appear to have increased risk of side effects from the Pfizer or Moderna COVID-19 vaccines, according to a recent Cedars-Sinai study as reported in a news release.
In fact, those being treated with advanced immune-modifying therapies may experience them less often than the general population.
IBDs, including Crohn's disease and ulcerative colitis, are chronic conditions that occur when the intestinal immune system becomes overreactive, causing chronic diarrhea and other digestive symptoms. In a published survey at the beginning of COVID-19 vaccine distribution, 70% of IBD patients reported concern about side effects from the vaccines.
The study is published online and upcoming in print in the American Journal of Gastroenterology.
"What we've learned is that if you have IBD, the side effects you're likely to experience after a vaccine are no different than they would be for anyone else," said Gil Melmed, MD, Director of Inflammatory Bowel Disease Clinical Research at Cedars-Sinai.
Patients with IBD and other immune-related conditions on biologic therapies were excluded from COVID-19 vaccine trials, so Melmed and fellow researchers evaluated post-vaccination side effects in 246 adult IBD patients in a nationwide COVID-19 vaccine registry used by investigators at Cedars-Sinai.
These patients, like those in the general population, most often reported pain and swelling at the injection site, followed by fatigue, headache and dizziness, fever and chills, and gastrointestinal symptoms. Most side effects were mild and lasted only a few days.
Very few IBD patients reported severe side effects – most commonly fatigue, fever and headache. And just two of the 246 patients studied reported severe gastrointestinal symptoms.
Many IBD patients expressed concern that vaccination would cause a "flare" or worsening of their condition. Research into whether post-vaccination GI symptoms were from flares or simply reactions to the vaccine is ongoing. However, Melmed emphasized that the vast majority of reported gastrointestinal symptoms were short-lived and resolved on their own.
Around 80% of patients in the study were being treated with advanced therapies that inhibit the body's immune response in a targeted way, including various biologic and Janus kinase inhibitor therapies. Melmed said this inhibition of the immune system might partially explain the slightly lower number of side effects these patients reported.
The current study of IBD patients is being extended for 5 years to help researchers determine whether – because their immune systems are being modulated by IBD treatment – they are receiving less protection from COVID-19 vaccines.
