title: Does gender influence morbidity or mortality in the surgical treatment of renal masses?
abstract: BACKGROUND
  We determine the relationship between gender and surgical morbidity after radical nephrectomy (RN) and partial nephrectomy (PN) for renal masses on a population level.
  
  
  METHODS
  We conducted a population-based, retrospective study using the Canadian Institute for Health Information Discharge Abstract Database. This included 20 286 RNs (82.5%) and 4292 PNs (17.5%) from April 1, 1998 to March 31, 2008. Complications were identified by ICD-9 and 10 codes, and comorbidity was assessed with the Charlson Index. The association between gender and in-hospital complication rates and mortality were examined using the Chi-square test, as well as with multivariable logistic regression, adjusting for explanatory variables including type of surgery, age, and comorbidity.
  
  
  RESULTS
  Overall, men experienced a higher unadjusted complication rate than women (35.1% vs. 32.7%), as well as a higher unadjusted in-hospital mortality rate (1.46% vs. 0.84%), respectively. Men also demonstrated significantly higher rates of cardiac, wound, nephrectomy-specific, and medical complications. Women experienced fewer complications than men after RN (p = 0.0002), but not after PN (p = 0.33). On multivariable logistic regression analysis, women had a lower overall complication rate (odds ratio [OR] 0.94, 95% confidence interval [CI] 0.88-0.99), and a lower inhospital mortality rate (OR 0.64, 95% CI 0.49-0.83) after kidney surgery.
  
  
  CONCLUSIONS
  In our population-based analysis, in-hospital morbidity after renal surgery was significantly lower for women. Further study is needed to determine if the observed effect is related to differences in surgical difficulty, perioperative care, or unmeasured confounders.
authors.affiliation: Urological Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH;
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Minnillo
authors.affiliation: Department of Surgical Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON;
authors.forename: Andrew
authors.initials: A
authors.lastname: Horowitz
authors.affiliation: Department of Surgical Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON;
authors.forename: Antonio
authors.initials: A
authors.lastname: Finelli
authors.affiliation: Department of Medicine, University of Toronto, Toronto, ON.
authors.forename: Shabbir M H
authors.initials: SM
authors.lastname: Alibhai
authors.affiliation: Urological Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH;
authors.forename: Lee E
authors.initials: LE
authors.lastname: Ponsky
authors.affiliation: Urological Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH;
authors.forename: Robert
authors.initials: R
authors.lastname: Abouassaly