The risk of cholecystitis in patients with cancer and the general population in a population-based cohort study in Western Denmark, 1995–2003

Abstract

20598 Background: Little information is available on the risk of cholecystitis among patients with cancer. Methods: We conducted a population-based retrospective cohort study of 51,350 patients with incident cancer, identified in medical databases of Western Denmark between 1995 and 2003. A general population comparison cohort of 513,500 persons frequency-matched on the age and sex distribution of the cancer cohort was assembled from the Danish Civil Registration System. The incidence of cholecystitis in the two cohorts was determined by linkage to the regional Hospital Discharge Registry covering all hospitals in the region. Results: We identified 230 incident diagnoses of cholecystitis in our cancer cohort during 130,628 person-years of follow-up, corresponding to an incidence rate of 1.8/1000 person-years. After adjustment for potential confounders, the adjusted relative risk (aRR) for cholecystitis among cancer patients compared with the general population cohort was 1.38 (95% confidence interval (CI) 1.20–1.58). Overall, the aRR for cholecystitis was doubled during the first six months after cancer diagnosis (aRR=1.95, 95% CI 1.50–2.54), at which point the aRR declined but remained greater than 1 throughout the rest of the follow-up period (aRR=1.23, 95% CI 1.05–1.45). Age-specific adjusted RRs ranged from 1.44 to 2.11 among cancer patients up to 70 years of age but were only marginally increased in cancer patients aged greater than 70 years. There were no major differences in aRRs between metastatic and non-metastatic cancer patients. Pancreatic cancer (aRR=6.71, 95% CI 3.82–11.76), thyroid cancer (aRR=3.83, 95% CI 1.60–9.22), and colorectal cancer (aRR=2.06, 95% CI 1.33–3.20) conferred the highest adjusted relative risks for subsequent cholecystitis. Conclusions: Cholecystitis occurs more often in cancer patients than in the general population. Pancreatic, thyroid and colorectal cancer seem to confer an especially high relative risk for subsequent cholecystitis, particularly during the first six months following diagnosis and among younger patients. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Expert Testimony Other Remuneration Amgen Inc. Amgen Inc.