title: Long-term follow-up and development of diverticulitis in patients diagnosed with diverticulosis of the colon.
abstract: BACKGROUND
  Diverticulosis of the colon is the most occurring abnormality in the digestive tract. Little is known on the risk of developing diverticulitis.
  
  
  OBJECTIVE
  The study aims to assess the risk of diverticulitis.
  
  
  METHODS
  All patients undergoing colonoscopy in the years 1998, 1999, and 2000 were studied. Patients with cancer, inflammatory bowel disease, anastomoses, and prior diverticulitis were excluded. In the summer of 2015, all hospital records, endoscopy reports, and reports from the department of radiology were studied. Diverticulitis had to be confirmed by the clinical presentation but also via ultrasound or CT scan. In order to obtain enough follow-up years, patients above the age of 75 years were excluded.
  
  
  RESULTS
  After exclusions, a study group of 433 patients remained. There was no difference is gender between patients developing diverticulitis and those who did not. There was no difference in age at time of the index colonoscopy. The sum of follow-up years was 6191. Range of follow-up was 0 to 17 years. The mean follow-up was 14.1 years per patient. Thirty cases of diverticulitis (7 %) could be identified; this is 4.8 cases per 1000 years. The mean time to development of diverticulitis was 5.9 years. Diverticulitis had a mild presentation in 19 patients and a severe presentation needing surgical intervention in 11.
  
  
  CONCLUSIONS
  The risk of developing diverticulitis is low. This contradicts the belief that diverticulosis has a high rate of progression. These results can help inform patients with diverticulosis about their risk of developing acute diverticulitis.
authors.affiliation: Department of Gastroenterology and Internal Medicine, Zaans Medisch Centrum, PO BOX 210, 1500 EE, Zaandam, The Netherlands. loffeld.r@zaansmc.nl.
authors.forename: R J L F
authors.initials: RJ
authors.lastname: Loffeld
mesh_terms: D000328:Adult; D000368:Aged; D002423:Cause of Death; D004238:Diverticulitis / Q000209:etiology*; D004241:Diverticulum, Colon / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D013997:Time Factors
keywords: Colonoscopy; Diverticulitis; Diverticulosis; Epidemiology; Follow-up