Vedolizumab Not Associated With Increased Risk of C Diff in Patients With IBD, Study Finds

Author(s):

Vedolizumab, anti-TNF, and 5-ASA treatments were not linked to an increased risk of CDI, but investigators noted other baseline variables were significantly associated with CDI risk in patients with IBD.

Abdulaziz Saad Alshahrani, MD

Credit: Virtual Medical Academy

Patients with inflammatory bowel disease (IBD) treated with vedolizumab are not at an increased risk of Clostridium difficile infection (CDI) compared to patients treated using other therapies, according to findings from a retrospective cohort study.

Results showed no difference in time to CDI between the vedolizumab, anti-TNF, and 5-Aminosalicylates acid (5-ASA) groups (log rank p-value 0.37) and found none of the treatments were associated with an increased risk of CDI.¹

CDI is often associated with use of antibiotics, but a weakened immune system is another significant risk factor.² Chronic intestinal inflammation associated with IBD can compromise gut immunity by wearing down mucosa in the intestinal lining and increase susceptibility to CDI.³

To evaluate the risk of CDI among patients with IBD using vedolizumab compared to other treatments, a team of investigators led by Abdulaziz Saad Alshahrani, MD, assistant professor of Gastroenterology at Najran University in Najran, Saudi Arabia, conducted a retrospective cohort study of 684 patients with confirmed IBD at a tertiary referral center at McMaster University Medical Centre (MUMC) in Hamilton, Ontario, Canada between January 2009 and August 2019. For inclusion, patients were required to have an established IBD diagnosis, initiation of vedolizumab, anti-TNF therapy, or 5-ASA supervised by a gastroenterologist at MUMC, and at least 2 years of follow-up data from the time of drug initiation.¹

Among the selected cohort, investigators noted 228 patients were on vedolizumab, 228 were on anti-TNF, and 228 were on 5-ASA. Crohn disease was more prevalent in the anti-TNF group (73.2%) while ulcerative colitis and IBD-unclassified were more prevalent in the 5-ASA group (73.7% and 2.6%, respectively). In the anti-TNF group, 30.7% of patients were treated by concomitant immunomodulator compared to 6.6% in the vedolizumab and 15.4% in the 5-ASA groups.¹

The primary outcome of interest was time to the development of CDI in IBD patients using different therapies. Secondary outcomes included rates of CDI and the association between baseline variables including drug treatment, age at start of drug therapy, smoking status, and use of corticosteroids or immunomodulators at time of drug initiation and risk of CDI. Investigators used a Cox proportional hazards regression model with stepwise selection to account for potential confounding factors.¹

Upon analysis, CDI occurred in 16 patients, including 4 in the vedolizumab group, 4 in the anti-TNF group, and 8 in the 5-ASA group. The median time to CDI was 7 months (Interquartile Range [IQR], 3–14) in patients using vedolizumab, 3 months (IQR, 1–20) in patients using anti-TNF, and 12 months (IQR, 6–14) in patients using 5-ASA. Investigators pointed out there were no significant differences between the three groups in median age, drug therapy used to treat CDI, or success of initial treatment.¹

Advanced age (Hazard Ratio [HR], 1.08; 95% Confidence Interval [CI], 1.05-1.12; P < 0.001), active smoking status (HR, 13.06; 95% CI, 3.84-44.45; P < 0.001), and concomitant immunomodulator use (HR, 2.91; 95% CI, 1.04-8.20; P = 0.0045) were all significantly associated with increased risk for CDI. Of note, treatment with biologics or 5-ASA was not found to be associated with risk of CDI in the model.¹

“Clinicians should always consider CDI in the differential diagnosis when IBD patients present with diarrhea, and in particular should exercise high caution in those with risk factors identified in this study,” wrote investigators.¹

References:

Alshahrani AS, Mohammad D, Alzahrani MA, Narula N. Vedolizumab does not increase risk of clostridium difficile infection in patients with inflammatory bowel disease using vedolizumab: A retrospective cohort study. Saudi Pharmaceutical Journal (2023). https://doi.org/10.1016/j.jsps.2023.101736
Centers for Disease Control and Prevention. C. diff (Clostridioides difficile). What is C. diff? Accessed September 5, 2023. https://www.cdc.gov/cdiff/what-is.html
Cleveland Clinic. C. diff (Clostridioides difficile) Infection. Overview. Accessed September 5, 2023. https://my.clevelandclinic.org/health/diseases/15548-c-diff-infection