Cancer risk and chemoprevention in Chinese inflammatory bowel disease patients: a population-based cohort study
Creators: name: Mak, Joyce Wing Yan
name: So, Jacqueline
name: Tang, Whitney
name: Yip, Terry Cheuk Fung
name: Leung, Wai Keung
name: Li, Michael
name: Lo, Fu Hang
name: Ng, Ka Man
name: Sze, Shun Fung
name: Leung, Chi Man
name: Tsang, Steven Woon Choy
name: Shan, Edwin Hok Shing
name: Chan, Kam Hon
name: Belsy C.Y. Lam
name: Hui, Aric J.
name: Chow, Wai Hung
name: Chan, Francis Ka Leung
name: Siew Chien Ng
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: FOS: Biological sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: FOS: Clinical medicine
subject: Cancer
subject: Science Policy
subject: Computational Biology

description: <b>Background and aim:</b> Role of 5-aminosalicylic acid (5-ASA), statin and aspirin in reducing cancer risks in inflammatory bowel disease (IBD) remains controversial. We aimed to examine chemo-preventive effects of these drugs in all cancers in IBD in population-based setting. <b>Methods:</b> IBD patients diagnosed between 2000 and 2016 were identified from the Hong Kong IBD Registry and followed from IBD diagnosis until first cancer occurrence. Primary outcome was cancer development ≥6 months after IBD diagnosis. Adjusted hazard ratio (aHR) with 95% confidence interval (CI) was estimated with Cox proportional hazards model. Additional effects of statin and aspirin on chemoprevention were also assessed. <b>Results:</b> Amongst 2103 IBD patients (857 Crohn’s disease, 1246 ulcerative colitis; mean age 40.0 ± 15.6; 60.3% male) with 16,856 person-years follow-up, 48 patients (2.3%) developed cancer. The 5-r, 10-r and 15-year (95% CI) cumulative incidence of cancer were 1% (0.6 − 1.5%), 2.8 (2.0 − 3.9%) and 4.8 (3.4 − 6.5%), respectively. Total 1891 (89.9%) and 222 (10.6%) patients have received one or more prescriptions of 5-ASA and statin respectively. In multivariable analysis adjusted for age, gender, smoking status, IBD type and use of other medications, use of 5-ASA or statin was not associated with a reduced risk of cancer development (5-ASA: aHR 1.22, 95% CI: 0.60–2.48, <i>p</i> = .593; statin: aHR 0.48, 95% CI: 0.14–1.59, <i>p</i> = .227). Adding aspirin was not associated with a lowered cancer risk (aHR 1.18, 95% CI: 0.32–4.35, <i>p</i> = .799). <b>Conclusion:</b> Use of 5-ASA was not associated with a lowered cancer risk in Chinese IBD patients. Addition of statin/aspirin provided no additional benefit.Key summaryInflammatory bowel diseases (IBD) including Crohn’s disease and ulcerative colitis are associated with increased risk of both intestinal and extra- intestinal cancers.Various medications including 5-aminosalicylate acid (5-ASA), statins and aspirin have been studied for their chemoprevention effects. However, most studies focused on colorectal cancer only and showed conflicting evidence. No studies so far looked at the effects of these medications on all cancer development in IBD.The 5-, 10- and 15-year (95% confidence interval) cumulative incidence of cancer in Chinese IBD patients were 1 (0.6–1.5%), 2.8 (2.0–3.9%) and 4.8 (3.4–6.5%), respectively.Use of 5-ASA was not associated with a lowered cancer risk in Chinese IBD patients. Addition of statin/aspirin provided no additional benefit. Inflammatory bowel diseases (IBD) including Crohn’s disease and ulcerative colitis are associated with increased risk of both intestinal and extra- intestinal cancers. Various medications including 5-aminosalicylate acid (5-ASA), statins and aspirin have been studied for their chemoprevention effects. However, most studies focused on colorectal cancer only and showed conflicting evidence. No studies so far looked at the effects of these medications on all cancer development in IBD. The 5-, 10- and 15-year (95% confidence interval) cumulative incidence of cancer in Chinese IBD patients were 1 (0.6–1.5%), 2.8 (2.0–3.9%) and 4.8 (3.4–6.5%), respectively. Use of 5-ASA was not associated with a lowered cancer risk in Chinese IBD patients. Addition of statin/aspirin provided no additional benefit.