Korean Patients With IBD at Increased C Difficile Risk, Study Says

There is an approximate 7-fold increased risk of Clostridioides difficile in Korean patients with inflammatory bowel disease (IBD) compared with that of age- and sex-matched non-IBD controls, according to a study published in BMJ Open Gastroenterology.

The researchers explained that a steady global increase of C difficile incidents has been reported in Asian countries. Patients with IBD often have certain C difficile risk factors, like frequent hospitalization and long-term immunosuppression. Because of this, diagnosing C difficile in patients with IBD is particularly difficult since C difficile symptoms are like those of IBD flare-ups.

Consequently, patients with IBD may experience C difficile diagnostic delays, which could result in fatal outcomes, like total colectomy or mortality. The researchers explained that it is important to understand C difficile prevalence and associated risk factors to appropriately diagnose it in those with symptomatic IBD. However, there is currently limited data available to describe the risk factors and epidemiology of C difficile, especially in Asian patients with IBD. Consequently, using data from the National Health Insurance Service (NHIS), the researchers conducted a population-based study to investigate the prevalence and risk factors of C difficile in Korean patients with IBD.

To conduct this study, the researchers identified patients with IBD and sex- and age-matched non-IBD controls in the NHIS database using International Classification of Diseases, 10th revision (ICD-10) diagnostic codes, as well as V codes from the Rare Intractable Diseases (RID) database, between 2008 and 2018. They compared the year-end prevalence and cumulative incidence of C difficile among those with either Crohn’s disease (CD) and ulcerative colitis (UC) with non-IBD controls; the researchers also examined the risk factors for C difficile in patients with IBD.

C difficile risk was significantly higher in Korean patients with IBD than in the non-IBD controls. | Image Credit: eddows -stock.adobe.com

They identified 55,052 patients with IBD aged between the ages of 19 and 79 from 2008 to 2018 and selected sex- and 10-year age-matched non-IBD controls at a matching ratio of 1:2. Overall, the study population consisted of 54,836 patients with IBD (38,231 with UC; 16,605 with CD), as well as 109,178 non-IBD controls. The researchers noted that the mean (standard deviation [SD]) ages at C difficile diagnosis of those with CD, those with UC, and those in the non-IBD control group were 37.5 (19.8), 49.1 (18.6), and 62.4 (13.9) years, respectively (P < .001); IBD patients were younger than the non-IBD control group with C difficile.

Of the study population, C difficile cases occurred within 293 patients with IBD (206 patients with UC; 87 patients with CD) and 82 of the age- and sex-matched non-IBD controls. The researchers explained that the annual year-end prevalence of C difficile in those with IBD increased from 8.6 patients out of every 10,000 in 2008 to 22.3 patients out of every 10,000 in 2018. More specifically, 1.5 of every 10,000 patients with CD in 2008 were diagnosed with C difficile, which increased to 23.7 patients out of every 10,000 in 2018; for patients with UC, 11.7 patients out of every 10,000 were diagnosed with C difficile in 2008, which increased to 21.6 patients of every 10,000 in 2018.

Overall, C difficile risk was significantly higher in Korean patients with IBD than in the non-IBD population (CD: hazard ratio [HR], 7.285; 95% CI, 5.388-9.851; and UC: HR, 7.285; 95% CI, 5.796-9.670; P < .001 for both); the researchers noted that this trend was comparable to that observed in Western patients with IBD. They performed a Cox regression analysis to investigate the risk factors influencing C difficile infection in these populations. In the general population, they noted that C difficile risk factors included IBD (CD and UC), female sex, and older age. Also, of those with IBD, the risk factors significantly associated with C difficile occurrence included female sex, older age, high CCI scores, and IBD-related medications, such as steroid use for longer than 90 days.

The researchers also acknowledged their study’s limitations, one being that the NHIS database does not include data on disease behavior and the extent of IBD; because of this, they did not evaluate C difficile risk according to IBD subtypes. Also, although the researchers evaluated risk according to IBD medication use, they did not include information regarding the doses. Despite these limitations, the researchers made future research suggestions based on their findings.

“Although our study showed a continuous increase of 156% in the annual year-end prevalence of C difficile in patients from 2008 to 2018, further studies are needed to determine whether this trend will persist or shift toward a plateau or downward trend, as observed in Western studies,” the authors concluded.

Reference

Song EM, Choi A, Kim S, Jung SH. The prevalence and risk factors of Clostridioides difficile infection in inflammatory bowel disease: 10-year South Korean experience based on the national database. J Korean Med Sci. 2023;38(47):e359. doi:10.3346/jkms.2023.38.e359