Treatment of diverticular disease of the colon and prevention of acute diverticulitis: a systematic review

BACKGROUND: Diverticular disease of the colon is a common disorder, characterized by recurrent symptoms and complications such as diverticulitis, requiring hospital admissions and surgery. OBJECTIVE: This study aimed to systematically review the evidence for medical therapy of diverticular disease in reducing symptoms and preventing acute diverticulitis. DATA SOURCES: MEDLINE and Embase databases (1966 to February 2010). STUDY SELECTION: The studies selected were prospective clinical trials on uncomplicated diverticular disease of the colon. INTERVENTIONS: Four investigators independently reviewed articles, extracted data, and assessed study quality according to standardized criteria. MAIN OUTCOME MEASURES: The main outcomes measured were improvement in symptoms, complete remission of symptoms, and prevention of acute diverticulitis. RESULTS: We identified 31 studies, including 6 placebo-controlled trials. The methodological quality of these studies was suboptimal. Only 10 trials provided a detailed description of the patient history, 8 assessed symptoms by the use of a validated questionnaire, and 14 appropriately defined inclusion and exclusion criteria. Only one long-term double-blind placebo-controlled study was identified. This reported a significant improvement in symptoms and greater prevalence of symptom-free patients at 1 year with fiber plus rifaximin in comparison with fiber alone. The efficacy of treatment in preventing acute diverticulitis was evaluated in 11 randomized trials. Four trials compared rifaximin plus fiber vs fiber alone and failed to show a significant difference between treatments. However, cumulative data from these trials revealed a significant benefit following rifaximin and fiber (1-year rate of acute diverticulitis: 11/970 (1.1%) vs 20/690 (2.9%); P = .012), but with a number needed to treat of 57, to prevent an attack of acute diverticulitis. LIMITATIONS: Heterogeneity of the study design, patients' characteristics, regimens and combination of studied treatment, and outcome reporting precluded the pooling of results and limited interpretation. CONCLUSIONS: The treatment for diverticular disease relies mainly on data from uncontrolled studies. Treatment showed some evidence of improvement in symptoms, but its role in the prevention of acute diverticulitis remains to be defined.