title: Coexisting liver disease is associated with increased mortality after surgery for diverticular disease.
abstract: BACKGROUND
  Coexistence of liver disease in patients undergoing surgery for diverticular disease (DD) may increase the risk of postoperative complications, but the evidence is limited.
  
  
  OBJECTIVE
  To investigate the impact of liver disease on mortality and reoperation rates following surgery for DD.
  
  
  METHODS
  We performed a cohort study based on medical databases of all patients undergoing surgery for DD in Denmark during 1977-2011, categorizing them into three cohorts according to history of liver disease: patients with non-cirrhotic liver disease, those with liver cirrhosis, and those without liver disease (comparison cohort). Using the Kaplan-Meier method, we computed mortality in each cohort for 0-30, 31-60, and 61-90 days following surgery for DD. We used a Cox regression model to compute hazard ratios as measures of the relative risk (RR) of death, controlling for potential confounders, including other comorbidities. In addition, we assessed the reoperation rate within 30 days of initial surgery.
  
  
  RESULTS
  Of 14,408 patients undergoing surgery for DD, 233 (1.6 %) had non-cirrhotic liver disease and 91 (0.6 %) had liver cirrhosis. Thirty-day mortality was 9.9 % in patients without liver disease and 14.6 % in patients with non-cirrhotic liver disease [adjusted RR = 1.64 (95 % confidence interval [CI] 1.16-2.31)]. Among patients with liver cirrhosis, mortality was 24.2 % [adjusted RR = 2.70 (95 % CI 1.73-4.22)]. Liver cirrhosis had an impact on mortality up to 60 days after surgery for DD. The reoperation rate was approximately 10 % in each cohort.
  
  
  CONCLUSIONS
  Preexisting liver disease has a major impact on postoperative mortality following surgery for DD.
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Århus N, Denmark, jonathan.montomoli@gmail.com.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Montomoli
authors.forename: Rune
authors.initials: R
authors.lastname: Erichsen
authors.forename: Lisa L
authors.initials: LL
authors.lastname: Strate
authors.forename: Lars
authors.initials: L
authors.lastname: Pedersen
authors.forename: Tove
authors.initials: T
authors.lastname: Nilsson
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004241:Diverticulum, Colon / Q000150:complications* / Q000401:mortality* / Q000601:surgery; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008107:Liver Diseases / Q000150:complications* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012042:Registries; D012086:Reoperation / Q000706:statistics & numerical data; D012307:Risk Factors