Dietary restrictions for acute diverticulitis: evidence-based or expert opinion?

Diet restrictions are usually advised as part of the conservative treatment for the acute phase of a diverticulitis episode. To date, the rationale behind diet restrictions has never been thoroughly studied. This study aims to investigate which factors influence the choice of dietary restriction at presentation. Additionally, the effect of dietary restrictions on hospitalization duration is investigated.

All patients hospitalized for Hinchey 0, Ia, or Ib diverticulitis between January 2010 and June 2011 were included. Patients were categorized according to the diet imposed by the treating physician at presentation and included nil per os, clear liquid, liquid diet, and solid foods. The relation between Hinchey classification, C-reactive protein, leucocyte count and temperature at presentation and diet choice was examined. Subsequently, the relation between diet restriction and number of days hospitalized was studied.

Of the 256 patients included in the study 65 received nil per os, 89 clear liquid, 75 liquid diet, and 27 solid foods at presentation. Solely high temperature appeared to be related to a more restrictive diet choice at presentation. Patients who received liquid diet (HR 1.66 CI 1.19-2.33) or solid foods (HR 2.39 CI 1.52-3.78) were more likely to be discharged compared to patient who received clear liquid diet (HR 1.26 CI 1.52-3.78) or nils per os (reference group). This relation remained statistically significant after correction for disease severity, treatment and complications.

Physicians appeared to prefer a more restrictive diet with increasing temperature at presentation. Notably, dietary restrictions prolong hospital stay.