(A-044) Biologic Therapy and All-cause Cancer Risk in Patients with Inflammatory Bowel Disease: A Nested Case-Control study

Background: Biologics are effective in treating inflammatory bowel disease (IBD); however, concerns remain regarding their potential association with malignancy. Despite these concerns, large-scale studies investigating the association between biologics use and malignancy are limited.

Objectives: To identify the characteristics and the association between biologic therapy and the risk of cancer in patients who are diagnosed with IBD.

Methods: We analyzed the Health Insurance Review and Assessment Service claims database from January 2007 to December 2022. Our study included patients newly diagnosed with Crohn’s disease (CD) or ulcerative colitis (UC) who had received at least one prescription for CD or UC-related medication between their diagnosis and December 2021. Among patients with no prior history of cancer at the time of their CD or UC diagnosis, cases were defined as those who subsequently developed any cancer. Controls were matched 1:4 with cases by age, sex, IBD subtype, and year of IBD diagnosis. To minimize the possibility of reverse causality, biological use was classified based on a 90-day lag: recent (use within 90 to 365 days before cancer) and persistent (recent use and use more than 365 days before cancer). Conditional logistic regression was used to calculate the odds ratio (OR) along with 95% confidence intervals (CI) and adjust for insurance type, the Charlson comorbidity index, and the use of immunomodulators.

Results: After matching IBD patients precisely, 3,069 were classified as cases and 12,276 as controls. The number of cases aged over 50 was 1,680 (54.74%), with a mean age of 50.07 (±15.14). The majority of cases were male (1,627, 53.01%), and UC was the predominant subtype (2,437, 79.41%). Among cases, there were 278(9.05%) recent use, and 67(2.18%) were persistent use. In conditional logistic regression, an increased adjusted OR was demonstrated for recent biologics use at 1.41 (95% CI, 1.08-1.85) and for persistent use at 1.15 (95% CI, 0.69-1.92).

Conclusions: The use of biologics in the year before an all-cause cancer diagnosis in patients with IBD has demonstrated a significant association with cancer occurrence. It is essential to monitor biological therapy based on its duration closely.