title: Role of acute diverticulitis in the development of complicated colonic diverticular disease and 1-year mortality after diagnosis in the UK: population-based cohort study.
abstract: OBJECTIVE
  To determine the risk of developing complicated colonic diverticular disease (CCDD) with prior episodes of acute diverticulitis and determine the mortality of the spectrum of CCDD.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  Computerised records from the General Practice Research Database linked to Hospital Episode Statistics data from the UK.
  
  
  METHODS
  Patients and controls registered in the General Practice Research Database from 1990 to 2007.
  
  
  METHODS
  Mortality was calculated and Cox regression modelling used to provide adjusted HRs and 95% CI. Logistic regression was used to model the effect of prior acute diverticulitis on the development of complications.
  
  
  RESULTS
  2950 patients (1872 (63.5%) female) had a diagnosis of CCDD (8739 controls). A total of 1042 (35.3%) patients died compared with 2062 (23.6%) controls. Most excess deaths occurred in the first year after the complication. Patients with a perforation/abscess had a 4.5-fold increase in 1-year mortality (HR 4.55, 95% CI 3.74 to 5.52) compared with the general population, whereas those with a fistula or stricture had a 2.5-fold increase in mortality (fistula HR 2.60, 95% CI 1.47 to 4.62; stricture HR 2.41, 95% CI 1.86 to 3.11). Although most patients (2133 (72.3%)) had suffered no prior episodes of acute diverticulitis, increasing episodes of acute diverticulitis were associated with an increased risk of developing a fistula (two or more prior episodes, OR 1.54 95%, CI 1.08 to 2.19), but there was no clear relationship with stricture or perforation/abscess.
  
  
  CONCLUSIONS
  Although most patients have experienced no prior episodes of acute diverticulitis, fistula formation is preceded by bouts of inflammation. Excess 1-year mortality across the spectrum of CCDD compared with the general population is substantial.
authors.affiliation: NIHR Clinical Lecturer in Surgery, NIHR Nottingham Digestive Disease Centre and Biomedical Research Unit, Department of Surgery, QMC Campus, E Floor, West Block, Nottingham University Hospital NHS Trust, Derby Road, Nottingham NG7 2UH, UK. david.humes@nottingham.ac.uk
authors.forename: David J
authors.initials: DJ
authors.lastname: Humes
authors.forename: Joe
authors.initials: J
authors.lastname: West
mesh_terms: D000038:Abscess / Q000209:etiology / Q000401:mortality; D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015331:Cohort Studies; D003251:Constriction, Pathologic / Q000209:etiology; D004239:Diverticulitis, Colonic / Q000150:complications* / Q000401:mortality; D005260:Female; D006801:Humans; D007412:Intestinal Fistula / Q000209:etiology / Q000401:mortality; D007415:Intestinal Obstruction / Q000209:etiology / Q000401:mortality; D007416:Intestinal Perforation / Q000209:etiology / Q000401:mortality; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012306:Risk; D006113:United Kingdom / Q000453:epidemiology