The incidence of cancer and mortality in paediatric onset inflammatory bowel disease in Denmark and Finland during a 23‐year period: a population‐based study

Abstract

Background: Recent studies report increased risks of both cancer and mortality in paediatric onset inflammatory bowel disease (pIBD) but the reproducibility of this is unknown. Aim: To estimate the risk of cancer and mortality in the Danish and Finnish pIBD population in a 23-year period compared to the general population. Methods: The pIBD population was defined as individuals registered in the national patient registries with a diagnosis of Crohn's disease (CD), ulcerative colitis (UC) or IBD-unclassified before their 18th birthday from 1992 to 2014. This cohort was cross referenced with the national cancer and mortality registries identifying all pIBD patients who subsequently developed cancer and/ or died and followed up to the end of 2014. Risk estimates are presented as standardised incidence ratios calculated based on incidence figures from the populations. Results: Six thousand six hundred and eight-nine patients with pIBD were identified (median age at follow-up 22.3 years; median follow-up: 9.6 years [interquartile range:4.8-16.0]). Seventy-two subsequently developed cancer and 65 died. The standardised incidence ratio of cancer in general was 2.6 (95% CI: 1.8-3.7) and 2.5 (95% CI: 1.8-3.4) in CD and UC, respectively. The standardised mortality ratios were 2.2 (95% CI: 1.4-3.4) and 3.7 (95% CI: 2.7-5.0) in CD and UC, respectively. The leading causes for mortality were cancer, suicide and infections. Conclusions:We found an increased risk of cancer and mortality in pIBD. This underlines the importance of cancer surveillance programs and assessment of mental health in the standard of care in adolescent pIBD patients. S U PP O RTI N G I N FO R M ATI O NAdditional supporting information will be found online in the Supporting Information section at the end of the article.How to cite this article: Malham M, Jakobsen C, Paerregaard A, Virta LJ, Kolho K-L, Wewer V. The incidence of cancer and mortality in paediatric onset inflammatory bowel disease in Denmark and Finland during a 23-year period: a populationbased study. Aliment Pharmacol Ther. 2019;50:33-39. https://

Editorial: suicide and IBD—a call to action. Authors’ reply

“…As stated in the editorial by Drs Banerjee and Gearry, the main result of the present study is the finding of an increased risk of cancer and mortality in pIBD with a surprisingly high risk of suicide. In contrast to the adult literature on this subject, the paediatric literature almost unambiguously reports an increased risk of cancer in pIBD and the main question is no longer if there's an increased risk but why.…”

“…The authors' declarations of personal and financial interests are unchanged from those in the original article …”

Paediatric onset inflammatory bowel disease is a distinct and aggressive phenotype—a comparative population‐based study

“…However, to our knowledge, no studies have investigated whether differences in disease course between pUC and aUC could be explained by differences in the initial disease extent. Lastly, recent reports have found an increased risk of cancer in pIBD, possibly due to a more extensive and aggressive disease state compared to aIBD …”

Editorial: suicide and IBD—a call to action

“…Usually when we consider causes of death in patients with IBD, cancer, venous thromboembolism, sepsis and nutrition are at the front of mind. However, the population‐based retrospective study by Malham et al has made us think more laterally about mortality in young people with IBD, and challenges us to be more vigilant for mental health issues.…”

“…In their study, Malham et al identified all Danish and Finnish patients diagnosed with paediatric inflammatory bowel disease (pIBD) over a 23‐year period . They cross‐linked each patient to the national cancer registries and the national cause of death registries to estimate cancer and mortality risks for their pIBD cohort.…”