Elevated venous thromboembolism risk following colectomy for IBD is equal to those for colorectal cancer for ninety days after surgery

BACKGROUND: The risk of postoperative venous thromboembolism is high in patients with colon cancer and IBD. Although The American Society of Colon and Rectal Surgeons suggests posthospital prophylaxis after surgery in patients with colon cancer, there are no such recommendations for patients with IBD. OBJECTIVE: This study aims to analyze the incidence and risk factors for postoperative venous thromboembolism. DESIGN: This was a retrospective review using the Explorys platform. SETTINGS: Aggregated electronic medical records from 26 major health care systems across the United States from 1999 to 2017 were used for this study. PATIENTS: Patients who underwent colon surgery were included. MAIN OUTCOME MEASURES: Patients were followed up to 90 days postoperatively for deep vein thrombosis and pulmonary embolism. RESULTS: A total of 75,620 patients underwent colon resections, including 32,020 patients with colon cancer, 9850 patients with IBD, and 33,750 patients with diverticulitis. The 30-day incidence of venous thromboembolism was higher in patients with cancer and IBD than in patients with diverticulitis (2.9%, 3.1%, and 2.4%, p < 0.001 for both comparisons). The 30-day incidence of venous thromboembolism in patients with ulcerative colitis is greater than in patients with Crohn's disease (4.1% vs 2.1%, p < 0.001). The cumulative incidence of venous thromboembolism increased from 1.2% at 7 days after surgery to 4.3% at 90 days after surgery in patients with cancer, and from 1.3% to 4.3% in patients with IBD. In multivariable analysis, increase in the risk of venous thromboembolism was associated with cancer diagnosis, IBD diagnosis, age ≥60, smoking, and obesity. LIMITATIONS: This study was limited by its retrospective nature and by the use of the aggregated electronic database, which is based on charted codes and contains only limited collateral clinical data. CONCLUSIONS: Because of the elevated and sustained risk of postoperative thromboembolism, patients with IBD, especially ulcerative colitis, might benefit from extended thromboembolism prophylaxis similar to that of patients with colon cancer.