Contemporary emergency management and 1-year outcomes of colonic diverticulitis: a population-based cohort study

Background — To describe contemporary outcomes on index hospitalization and 1-year outcomes from index discharge in patients with diverticulitis.

Study design — Population-based retrospective cohort study which included adult residents of Ontario, Canada, presenting to the emergency department (ED) with diverticulitis (January 2017-March 2022). For those hospitalized at the time of index ED presentation, the risk of urgent surgery, percutaneous drainage, and mortality are reported. Following index presentation discharge (from the ED or hospital with an intact colon), the cumulative incidence of unplanned hospitalization, urgent surgery, and scheduled surgery is reported at 30 days and 1 year, accounting for competing risks.

Results — Of 24,759 patients presenting to the ED with diverticulitis, 6,263 (25%) were hospitalized and required no intervention (N=5,379; 23%), while a minority required surgery (N=555, 2.2%) or percutaneous drainage (N=329; 1.3%). Following index presentation discharge, the cumulative incidence of unplanned hospitalization, urgent surgery and scheduled surgery were 2% (95% CI 2.1-2.4), 0.6% (95% CI 0.5-0.7%) and 0.06% (95% CI 0.03-0.09) at 30-days, and 7% (95% CI 6.7-7.3%), 1.3% (95% CI 1.2-1.5%) and 1.5% (95% CI 1.3-1.6) at 1-year, respectively. People managed with percutaneous drainage at index presentation were at higher 1-year risk: 44% (95%CI 29-39%) unplanned hospitalization and 11% (95%CI 8-14%) urgent surgery.

Conclusion — For the vast majority of patients, the disease course 1 year from index discharge remains benign, with only a small minority of patients requiring hospitalization or surgery. These outcome estimates can guide patient counselling, including the appropriateness of scheduled colectomy for diverticulitis.