Venous and arterial thromboembolism after colorectal cancer in the Netherlands: Incidence, predictors, and prognosis.

Background: Colorectal cancer (CRC) is the third most prevalent cancer type. CRC-patients are at increased risk of venous and arterial thromboembolism (TE), but the magnitude of the risks, their predictors and consequences are not exactly known.
Objectives: We aimed to determine incidence, predictors and prognosis of TE after incident CRC in a large, unselected population.
Methods: Using data from Statistics Netherlands and the Netherlands Comprehensive Cancer Organization, all incident CRC-patients were identified between 2013 and 2018 plus a sample of 1:2 age- and sex-matched control subjects. Incidence rates and cumulative incidences for TE were estimated. Predictor variables for TE were explored by univariable Cox regression. The association between TE and all-cause mortality was evaluated by multivariable time-dependent Cox regression.
Results: 68,238 incident CRC-patients were matched to 136,476 controls. CRC-patients had a 1-year cumulative venous TE (VTE) incidence of 1.93 % (95%CI 1.83-2.04), versus 0.24 % (95%CI 0.21-0.27) in controls (HR 8.85; 95%CI 7.83-9.99). For arterial TE (ATE), this was 2.74 % (95%CI 2.62-2.87) in CRC versus 1.88 % (95%CI 1.81-1.95) in controls (HR 1.57; 95%CI 1.47-1.66). Cancer stage, surgery, chemotherapy and asthma were predictors for VTE, whereas age, prior ATE and Parkinson's disease were predictors for ATE. CRC patients with TE had an increased risk of all-cause mortality (VTE HR; 3.68 (95%CI 3.30-4.10, ATE HR; 3.05 (95%CI 2.75-3.39)) compared with CRC-patients without TE.
Conclusions: This Dutch nationwide cohort study adds detailed knowledge on the risk of VTE and ATE, their predictors and prognosis in CRC-patients. These findings may drive TE prophylactic management decisions.
Competing Interests: Declaration of competing interest Q. Chen is supported by the Chinese Government Scholarship (No. 201906380148) for his PhD at the Leiden University Medical Center. Prof. Dr. Klok has received research support from Bayer, Bristol-Myers Squibb, Actelion, Boston Scientific, Leo Pharma, The Netherlands Organization for Health Research and Development, The Dutch Thrombosis Association, The Dutch Heart Foundation and the Horizon Europe program, all outside this work and paid to his institution.
(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)