Analysis of risk factors for colonic diverticular bleeding and recurrence

The increase in incidence of colonic diverticular bleeding is relative to an age-related rise in the incidence of colonic diverticulosis and use of antithrombotic medication. However, risk factors related to the onset, recurrence, and prophylaxis have not been established. Therefore, we aimed to determine risk factors for the onset and recurrence of colonic diverticular bleeding. An age-and sex-matched case-control study was performed to assess the risk factors for the onset of colonic diverticular bleeding. The distribution of diverticulosis, comorbidity, and medication were evaluated from medical records. We also assigned patients with a first-time bleeding into groups with and without rebleeding during follow-up to determine risk factors for recurrence. Bilateral colonic diverticulosis, nonselective nonsteroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin (LDA), and anticoagulants were significant risk factors for the onset of colonic diverticular bleeding on multivariate analysis. In contrast, the use of selective cyclooxygenase-2 (COX-2) inhibitor was not a risk factor for the onset. The incidence of bleeding in direct oral anticoagulant and warfarin users was not different between the 2 groups. The cumulative recurrence rate at 1 year was 15%. Recurrence rate was significantly higher in patients with a prior history of colonic diverticular bleeding than those without. Steroid use was associated with recurrence. Extensive distribution of diverticulosis and use of nonselective NSAIDs, LDA, and anticoagulants are regarded as risk factors for the onset of colonic diverticular bleeding. In addition, a prior history of colonic diverticular bleeding is related to the recurrence.