title: Renal surgery for kidney cancer in Germany 2005-2006: length of stay, risk of postoperative complications and in-hospital death.
abstract: BACKGROUND
  Representative statistics of surgical care among patients with kidney cancer are scant. With the introduction of the diagnosis related group system in Germany, it is now possible to provide nationwide statistics on surgical care. We studied in-hospital mortality risk in relation to comorbidity and complications, length of hospital stay in relation to surgical approach and comorbidity, and risk of complications in relation to surgical approach among kidney cancer patients undergoing nephrectomy.
  
  
  METHODS
  We analyzed the nationwide hospitalization file of the years 2005 and 2006 including 23,753 hospitalizations with a diagnosis of renal cancer and partial or complete nephrectomy and classified comorbidity (Charlson comorbidity index) and complications. Length of stay, risk of in-hospital complications and in-hospital death were analyzed by linear regression and log-linear regression (relative risks (RR) and 95% confidence intervals (95% CI)).
  
  
  RESULTS
  The overall in-hospital mortality was 1.4%. Per one unit increase of the Charlson comorbidity index, the adjusted risk of in-hospital mortality increased by 53% (95% CI 47-59%). The risks of bleeding or acute posthaemorrhagic anemia, respiratory, urological and gastrointestinal complications and infections ranged between 1.1% and 2.7% with the exception of bleeding or acute posthaemorrhagic anemia with 18.4%. Complications were associated with an increased adjusted in-hospital mortality risk. Highest adjusted mortality risk ratios were observed for gastrointestinal (RR = 3.61, 95% CI 2.32-5.63) and urological complications (RR = 3.62, 95% CI 2.62-5.00). The risk of haemorrhage or acute posthaemorrhagic anemia was lower for total laparoscopic nephrectomies than total open nephrectomies. The adjusted risk of gastrointestinal complications was lower for partial open compared to total open nephrectomy (adjusted RR = 0.66, 95% CI 0.45-0.97). Total laparoscopic nephrectomy was associated with shorter length of stay (-3.3 days; 95% CI 2.9-3.7 days) compared to total open nephrectomy. The estimated age-adjusted increase of length of stay per one unit increase of the Charlson comorbidity index was 1.3 days (95% CI 1.2-1.4 days).
  
  
  CONCLUSIONS
  In this representative population-based analysis, we found that the surgical approach is associated with the risk of complications and length of hospital stay. Furthermore, in the era of ageing populations, renal cancer patients with comorbidities should be counseled about their increased in-hospital mortality risk.
authors.affiliation: Institut für Medizinische Informatik, Biometrie, und Epidemiologie (IMIBE), Universitätsklinikum Halle, Halle, Essen 45147, Germany. andreas.stang@uk-essen.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Stang
authors.forename: Christian
authors.initials: C
authors.lastname: Büchel
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005858:Germany / Q000453:epidemiology; D017052:Hospital Mortality; D006801:Humans; D007431:Intraoperative Complications / Q000453:epidemiology; D007680:Kidney Neoplasms / Q000401:mortality* / Q000601:surgery*; D007902:Length of Stay; D008875:Middle Aged; D009392:Nephrectomy; D011183:Postoperative Complications / Q000453:epidemiology*; D012307:Risk Factors