Background: Previous studies suggest that elective colectomy is often required after an episode of acute diverticulitis.
Hypothesis: Acute diverticulitis initially treated nonoperatively does not require elective colectomy.
Design: Retrospective cohort study.
Setting: Twelve Kaiser Permanente hospitals in Southern California.
Patients: Three thousand one hundred sixty-five patients with acute diverticulitis.
Interventions: Colectomy or nonoperative treatment with or without percutaneous abscess drainage.
Main outcome measures: Recurrent diverticulitis.
Results: Emergency colectomy was performed in 614 patients (19.4%). Nonoperative treatment was initially used in 2551 patients (80.6%). Of these, 185 patients (7.3%) had an elective colectomy and the remaining 2366 patients (92.7%) did not. Factors associated with undergoing elective colectomy compared with nonoperative treatment were younger age of the patient, fewer comorbidities, and percutaneous abscess drainage. Mean follow-up was 8.9 years, with a maximum of 12 years. After nonoperative treatment, 314 patients (13.3%) recurred-222 patients had a single recurrence and 92 patients had a rerecurrence. After adjusting for other variables, older age (hazard ratio, >/=50 years vs <50 years = 0.68; 95% confidence interval, 0.53-0.87) was associated with a lower recurrence, whereas higher comorbidity was associated with higher recurrence. Gender and percutaneous abscess drainage had no influence on recurrence. All 92 rerecurrences were treated nonoperatively. The risk of a rerecurrence (29.3%) was significantly higher than a first recurrence (P<.001). Age, gender, Charlson comorbidity index, and percutaneous abscess drainage did not predict rerecurrence.
Conclusions: Very few patients with acute diverticulitis treated nonoperatively have recurrence. Younger age was associated with recurrence. A first recurrence was the only factor that predicted rerecurrences. The low recurrence rate argues against routine elective colectomy after successful nonoperative management of acute diverticulitis.