title: Mortality rate after nonelective hospital admission.
abstract: OBJECTIVE
  We hypothesized that the mortality rate after nonelective hospital admission is higher during weekends than weekdays.
  
  
  METHODS
  Retrospective cohort analysis.
  
  
  METHODS
  Patients admitted to hospitals in the Nationwide Inpatient Sample, a 20% sample of US community hospitals.
  
  
  METHODS
  We identified all patients with a nonelective hospital admission from January 1, 2003, through December 31, 2007, in the Nationwide Inpatient Sample. Next, we abstracted vital status at discharge and calculated the Charlson comorbidity index score for all patients. We then compared odds of inpatient mortality after nonelective hospital admission during the weekend compared with weekdays, after adjusting for diagnosis, age, sex, race, income level, payer, comorbidity, and hospital characteristics.
  
  
  METHODS
  Mortality rate.
  
  
  RESULTS
  Discharge data were available for 29,991,621 patients with nonelective hospital admissions during the 5-year study period: 6,842,030 during weekends and 23,149,591 during weekdays. Inpatient mortality was reported in 185,856 patients (2.7%) admitted for nonelective indications during weekends and 540,639 (2.3%) during weekdays (P < .001). The regression revealed significantly higher mortality during weekends for 15 of 26 (57.7%) major diagnostic categories. The weekend effect remained, and mortality was noted to be 10.5% higher during weekends (odds ratio, 1.10; 95% confidence interval, 1.10-1.11) compared with weekdays after adjusting for all other variables with the imputed data set.
  
  
  CONCLUSIONS
  These data demonstrate significantly worse outcomes after nonelective admission during the weekend compared with weekdays. Although the underlying mechanism of this finding is unknown, it is likely that factors such as differences in hospital staffing and services offered during the weekend compared with weekdays are causal and mutable.
authors.affiliation: Lahey Clinic, Department of Colorectal Surgery, Tufts University Medical School, 41 Mall Rd, Burlington, MA 01805, USA. rocco.ricciardi@lahey.org
authors.forename: Rocco
authors.initials: R
authors.lastname: Ricciardi
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Roberts
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Read
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Baxter
authors.forename: Peter W
authors.initials: PW
authors.lastname: Marcello
authors.forename: David J
authors.initials: DJ
authors.lastname: Schoetz
mesh_terms: D000328:Adult; D000368:Aged; D003695:Delivery of Health Care / Q000706:statistics & numerical data; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D010343:Patient Admission / Q000706:statistics & numerical data*; D010351:Patient Discharge / Q000706:statistics & numerical data; D011787:Quality of Health Care / Q000706:statistics & numerical data; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors; D014481:United States