Age- and sex-specific risk of colorectal cancer in incident ulcerative colitis during the first 10 years after diagnosis: a nationwide population-based study

Abstract

Objective

We assessed the risk of colorectal cancer (CRC) in patients with ulcerative colitis (UC) using the nationwide population-based claims data.

Materials and methods

We analyzed the claims data of the Korean National Health Insurance (2006–2015). UC and CRC were defined using ICD-10 codes and UC-specific prescriptions in this study. Age- and sex-matched individuals without UC were randomly selected from the general population. Hazard ratios (HRs), adjusted for different covariates, were calculated using multivariate Cox proportional hazard regression.

Results

In total, 30,546 and 88,829 individuals with and without UC, respectively, were enrolled. CRC developed in 85 (0.27%) among UC, and 340 (0.38%) among individuals without UC, respectively. The HR (95% confidence interval [CI]) of CRC in all UC patients was 0.74 (0.58–0.94). Further, UC patients were stratified according to sex (male vs. female: 0.60 [0.44–0.82] vs. 1.10 [0.75–1.61]) and age (HR = 14.37, 2.74, 0.58, and 0.70 for 0–19, 20–39, 40–59, and ≥60 years, respectively). HR was significantly higher for late-onset UC (≥60 years) than for early-onset UC (0–19 years). The long duration of 5-aminosalicylic acid use had a significantly low HR, with reference to the 1st quartile.

Conclusions

The risk of CRC varies with age and sex in Korean patients with UC during the first decade after diagnosis. Early-onset UC (<40 years) increases the CRC risk.

Keywords:

• Colorectal cancer
• ulcerative colitis
• risk factors

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by grants from the National Research Foundation of Korea [2019R1A2C1007859, Ministry of Science and ICT] and the National R&D Program for Cancer Control [HA17C0046, Ministry of Health and Welfare] funded by the Korean Government.