Colonoscopy and Risk of Colorectal Cancer in Patients With Nonalcoholic Fatty Liver Disease: A Retrospective Territory‐Wide Cohort Study

Abstract

The benefit of colonoscopy and/or polypectomy for colorectal cancer (CRC) prevention in patients with nonalcoholic fatty liver disease (NAFLD) remains unclear. We aimed to estimate the incidence rate of CRC in patients with NAFLD who had and had not undergone colonoscopy. We conducted a retrospective territory-wide cohort study for patients aged over 40 years with NAFLD identified with the International Classification of Diseases, Ninth Revision, Clinical Modification codes between January 1, 2000, and December 31, 2014. Patients were followed until CRC diagnosis, death, or December 31, 2017. We estimated CRC incidence and standardized incidence ratio (SIR) using the general population of Hong Kong as reference. We included 8,351 patients with NAFLD in the final analysis (median age, 56.2 years; interquartile ratio [IQR], 49.2-65.3 years; 45.4% male; median follow-up, 7.4 years; IQR, 5.4-9.6 years). Compared with the general population, patients with NAFLD who had not undergone colonoscopy had a higher incidence of CRC (SIR, 2.20; 95% confidence interval [CI], 1.64-2.88; P < 0.001). Patients with NAFLD who had undergone colonoscopy had a lower incidence of CRC (SIR, 0.54; 95% CI, 0.37-0.75; P < 0.001), especially among those aged above 50 years or with diabetes mellitus (DM). Patients with NAFLD with a high fibrosis-4 (FIB-4) score (>2.67) had a significantly higher risk of CRC after adjusting for demographic and metabolic factors. Conclusion: Patients with NAFLD who had undergone colonoscopy had a lower incidence of CRC than the general population, especially among those aged ≥50 years or with DM. A high FIB-4 index was associated with a higher risk of CRC. (Hepatology Communications 2021;0:1-12).

Risk of liver‐related events by age and diabetes duration in patients with diabetes and nonalcoholic fatty liver disease

“…The definitions of hypertension, dyslipidemia, coronary heart disease, congestive heart failure, and cerebrovascular events were described in our previous studies and are also shown in the Supporting Information. [11,14]…”

Metabolic Dysfunction–Associated Fatty Liver Disease Increases Colon Cancer Risk: A Nationwide Cohort Study

“…In our study, FLD was consistently associated with CRC risk in the presence or absence of liver fibrosis, suggesting that the risk of CRC development may be elevated even in a mild form of FLD without progression to advanced fibrosis. The significant association between FLD and incident CRC has important implications for CRC screening strategies, as demonstrated in a study by Zhang et al( 31 ), where patients with NAFLD who had not undergone colonoscopy exhibited a higher CRC risk than the general population, whereas those who had undergone colonoscopy evidenced a lower risk. We also found that MAFLD was associated with a higher risk of CRC even in the subgroup of youngest age (40–44 years), which is below the recommended CRC screening age ( 32 ).…”

Angiotensin‐converting enzyme inhibitors prevent liver‐related events in nonalcoholic fatty liver disease

“…CDARS is an electronic health care database that covers patients’ demographics, death, diagnoses, procedures, drug prescription and dispensing history, and laboratory results from all public hospitals and clinics in Hong Kong, which covers ~80% of the local population. [ 9 ] International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) coding was used in CDARS. When validated against a review of consultation notes and radiological and laboratory reports, the diagnosis of NAFLD by ICD‐9‐CM coding had a positive predictive value of 98.4%, and the diagnosis of cirrhosis complications had a positive predictive value of 85.7% and a negative predictive value of 95.9%.…”