Long-term follow-up after an initial episode of diverticulitis: what are the predictors of recurrence?

PURPOSE

The purpose of our study was to determine the clinical and CT predictors of recurrent disease after a first episode of diverticulitis that was successfully managed nonoperatively.

METHODS

We retrospectively analyzed 954 consecutive patients who presented to our institution with diverticulitis from 2002 to 2008. Patients were identified with International Classification of Diseases, 9th Revision/Current Procedural Terminology codes. Patients were excluded if they had subsequent colectomy based on the first attack (n = 81), or if the attack they had between 2002 and 2008 was not their first attack (n = 201). We evaluated CT variables chosen by a panel of expert gastrointestinal radiologists. These radiologists reviewed the available published literature for CT imaging characteristics thought to predict diverticulitis severity. CT variables (n = 20) were determined by prospective reevaluation of scans by blinded study radiologists. Clinical variables (n = 43) were coded based on a retrospective chart review. Univariate analysis of variables in relation to recurrent disease was performed by a log-rank test of Kaplan-Meier estimates. Multivariate analysis was performed using Cox proportional hazards modeling. Variables with P < .2 on univariate analysis were included in a stepwise selection algorithm.

RESULTS

The study population included 672 patients; mean age, 61 ± 15 years; mean follow-up, 42.8 ± 24 months. The index presentation of diverticulitis was most commonly located in the sigmoid colon (72%), followed by descending colon (33%), right colon (5%), and transverse colon (3%). Overall recurrence at 5 years was 36% by (95% CI 31.4%-40.6%) Kaplan-Meier estimate. Complicated recurrence (fistula, abscess, free perforation) occurred in 3.9% (95% CI 2.2%-5.6%) of patients at 5 years by Kaplan-Meier estimate. Family history of diverticulitis (HR 2.2, 95% CI 1.4-3.2), length of involved colon >5 cm (HR 1.7, 95% CI 1.3-2.3), and retroperitoneal abscess (HR 4.5, 95% CI 1.1-18.4) were associated with diverticulitis recurrence. Right colon disease (HR 0.27, 95% CI 0.09-0.86) was associated with freedom from recurrence.

CONCLUSION

Although diverticulitis recurrence is common following an initial attack that has been managed medically, complicated recurrence is uncommon. Patients who present with a family history of diverticulitis, long segment of involved colon, and/or retroperitoneal abscess are at higher risk for recurrent disease. Patients who present with right-sided diverticulitis are at low risk for recurrent disease. These findings should be taken into consideration when counseling patients regarding the potential benefits of prophylactic colectomy.