Abstract and Introduction
Background: Previous research indicates that the increased relative risk of colorectal cancer (CRC) in inflammatory bowel disease (IBD) is limited to young-onset IBD.
Aim: To estimate risks of incident CRC and death from CRC in elderly-onset IBD
Methods: Patients diagnosed with IBD at age ≥ 60 years between 1969 and 2017 were identified using Danish and Swedish National Patient Registers and histopathology data. We linked data to Cancer and Causes of Death Registers and used Cox regression to estimate hazard ratios (HRs) for CRC diagnosis and death compared to matched (by sex, age, and region) IBD-free individuals.
Results: Among 7869 patients with Crohn's disease followed for 54,220 person-years, and 21,224 patients with ulcerative colitis (UC) followed for 142,635 person-years, 2.10% and 1.90% were diagnosed with CRC, compared to 2.26% and 2.34% of reference individuals (median follow-up 6 and 7 years). The incidence of CRC was elevated during the first year after IBD diagnosis: 4.36 (95% CI = 3.33–5.71) in Crohn's disease and 2.48 (95% CI = 2.03–3.02) in UC, but decreased after the first year of follow-up: 0.69 (95% CI = 0.56–0.86) and 0.78 (95% CI = 0.69–0.88). Once diagnosed with CRC, the risk of CRC death was similar for IBD patients and the general population.
Conclusion: The excess risk of CRC in elderly-onset IBD was probably due to bias and not observed beyond the first year. From 2010, the HR for CRC diagnosis more than 1 year after initial IBD diagnosis was lower than in the largely unscreened reference population, supporting the benefit of endoscopic screening and surveillance in patients with IBD.
Existing evidence has established an increased risk of colorectal cancer (CRC) in patients with inflammatory bowel disease (IBD) both overall, and separately in patients with Crohn's disease (CD) and ulcerative colitis (UC).[3–5] The risk of CRC is higher in IBD patients with extensive disease,[1,3,4] a family history of CRC, primary sclerosing cholangitis (PSC), and long disease duration.[1,3] Current endoscopic surveillance programmes thus recommend varied colonoscopy intervals according to the presence of risk factors.[8,9]
When examining risks of CRC in relation to age at diagnosis, the highest relative risks of CRC has been reported for patients diagnosed with IBD at <30 years of age. The relative risk is significantly lower for patients with adult-onset IBD.[1,2,4] Approximately 4%–21% of patients with CD and 11%–25% of patients with UC are diagnosed at an elderly age (≥60–61 years).[10–14] For elderly patients, the underlying CRC risk is inherently higher than in younger patients, but the incidence of CRC in those with IBD has not been reported to be increased compared to age-matched peers without IBD, based on population-based studies conducted in the 2000s[15–18] (Table S1).
Although most studies found no excess incidence of CRC in patients with elderly-onset IBD, cancer surveillance programmes do not take age of onset into account when establishing surveillance intervals.[9,19] The aim of the current study was to examine the risk of CRC diagnosis and death in a large cohort of individuals with elderly-onset (60+ years) CD and UC, compared to matched reference individuals from the general population. This approach was taken to identify subgroups of elderly patients that might benefit from enhanced surveillance endoscopy.
Aliment Pharmacol Ther. 2022;56(7):1168-1182. © 2022 Blackwell Publishing