Progression rate of diverticular disease and associated risk factors: results from 5-year longitudinal prospective nationwide diverticular disease registry (REMAD).

Natural history of diverticular disease (DD) through its different subgroups (diverticulosis, symptomatic uncomplicated diverticular disease (SUDD) previous diverticulitis (PD)) is poorly defined. Few studies, mainly retrospective, have analysed its rate of progression and risk factors associated. We assessed the potential progression rate of different spectrum of DD and associated risk factors. Data from the REMAD Registry, a 5-year Italian longitudinal prospective multicentre study, were analysed. A total of 1217 patients were included that were divided into three subgroups (diverticulosis, SUDD and PD) and followed up every six months for 5 years. Amongst patients with colonic diverticulosis, about 7% progressed to SUDD with an average follow-up period of 18.3 (SD ± 16.1) months, whilst 1% had an acute episode of diverticulitis with a mean time to progression of 23.7 (SD ± 15.0) months. Amongst SUDD, 2.7% progressed to acute diverticulitis with a mean follow-up time of 29.2 (SD ± 17.1) months. Almost 20% of patients with PD had a first recurrence at a mean follow-up of 20.1 (SD ± 14.2) months, whilst 14.3% had a second recurrence at a mean follow-up of 15.6 (SD ± 7.0) months. Gender, diet (low fibre intake and meat consumption) being overweight, gastrointestinal tract medications and antiplatelet use are risk factors involved in DD progression. This longitudinal prospective study demonstrates a low progression rate in diverticulosis and SUDD, whereas diverticulitis recurrences are a frequent occurrence, representing the major clinical burden in DD. These results suggest that DD can progress, highlighting the need to understand how to prevent it from developing into a symptomatic and/or complicated form.