Colorectal Cancer Risk in Patients with Hemorrhoids: A 10-Year Population-Based Retrospective Cohort Study

En-Bo Wu; Fung-Chang Sung; Cheng-Li Lin; Kuen-Lin Wu; Kuen-Bao Chen

doi:10.3390/ijerph18168655

Colorectal Cancer Risk in Patients with Hemorrhoids: A 10-Year Population-Based Retrospective Cohort Study

Int J Environ Res Public Health. 2021 Aug 16;18(16):8655. doi: 10.3390/ijerph18168655.

Authors

En-Bo Wu¹, Fung-Chang Sung^{2

3

4}, Cheng-Li Lin³, Kuen-Lin Wu⁵, Kuen-Bao Chen^{1

6}

Affiliations

¹ Department of Anesthesiology, China Medical University Hospital, China Medical University, Taichung 404, Taiwan.
² Department of Health Services Administration, College of Public Health, China Medical University, Taichung 404, Taiwan.
³ Management Office for Health Data, China Medical University Hospital, Taichung 404, Taiwan.
⁴ Department of Food Nutrition and Health Biotechnology, Asia University, Taichung 413, Taiwan.
⁵ Division of Colorectal Surgery, Department of Surgery, Kaohsiung Chang-Gung Memorial Hospital and Chang-Gung University College of Medicine, Kaohsiung 833, Taiwan.
⁶ Department of Anesthesiology, College of Medicine, China Medical University, Taichung 404, Taiwan.

Abstract

Colorectal cancer (CRC) is a common disease and one of the leading causes of cancer deaths worldwide. This retrospective cohort study evaluated the risk of developing CRC in people with hemorrhoids. Using Taiwan's National Health Insurance Research Database, we established three sets of retrospective study cohorts with and without hemorrhoids. The first set of cohorts were matched by sex and age, the second set of cohorts were matched by propensity score without including colonoscopies, and the third set of cohorts were matched by propensity score with colonoscopies, colorectal adenomas, and appendectomies included. In the second set of cohorts, 36,864 persons with hemorrhoids that were diagnosed from 2000 to 2010 and a comparison cohort, with the same size and matched by propensity score, were established and followed up to the end of 2011 to assess the incidence and Cox proportional regression-measured hazard ratio (HR) of CRC. The overall incidence rate of CRC was 2.39 times greater in the hemorrhoid cohort than it was in the comparison cohort (1.29 vs. 0.54 per 1000 person-years), with a multivariable model measured adjusted HR of 2.18 (95% CI = 1.78-2.67) after controlling for sex, age, and comorbidity. Further analysis on the CRC incidence rates among colorectal sites revealed higher incidence rates at the rectum and sigmoid than at other sites, with adjusted HRs 2.20 (95% CI = 1.48-3.28) and 1.79 (95% CI = 1.06-3.02), respectively. The overall incidence rates of both cohorts were similar in the first and second sets of cohorts, whereas the rate was lower in the third set of hemorrhoid cohorts than in the respective comparison cohorts, probably because of overmatching. Our findings suggest that patients with hemorrhoids were at an elevated risk of developing CRC. Colonoscopy may be strongly suggested for identifying CRC among those with hemorrhoids, especially if they have received a positive fecal occult blood test result.

Keywords: colorectal cancer; hemorrhoid; propensity score matching; retrospective cohort study; risk factor.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cohort Studies
Colonoscopy
Colorectal Neoplasms* / epidemiology
Hemorrhoids* / epidemiology
Humans
Incidence
Retrospective Studies
Risk Factors