title: Preoperative factors affecting cost and length of stay for isolated off-pump coronary artery bypass grafting: hierarchical linear model analysis.
abstract: OBJECTIVE
  To determine the effect of preoperative patient and hospital factors on resource use, cost and length of stay (LOS) among patients undergoing off-pump coronary artery bypass grafting (OPCAB).
  
  
  METHODS
  Observational retrospective study.
  
  
  METHODS
  Data from the Japanese Administrative Database.
  
  
  METHODS
  Patients who underwent isolated, elective OPCAB between April 2011 and March 2012.
  
  
  METHODS
  The primary outcomes of this study were inpatient cost and LOS associated with OPCAB. A two-level hierarchical linear model was used to examine the effects of patient and hospital characteristics on inpatient costs and LOS. The independent variables were patient and hospital factors.
  
  
  RESULTS
  We identified 2491 patients who underwent OPCAB at 268 hospitals. The mean cost of OPCAB was $40 665 ±7774, and the mean LOS was 23.4±8.2 days. The study found that select patient factors and certain comorbidities were associated with a high cost and long LOS. A high hospital OPCAB volume was associated with a low cost (-6.6%; p=0.024) as well as a short LOS (-17.6%, p<0.001).
  
  
  CONCLUSIONS
  The hospital OPCAB volume is associated with efficient resource use. The findings of the present study indicate the need to focus on hospital elective OPCAB volume in Japan in order to improve cost and LOS.
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shinjo
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fushimi
mesh_terms: D000368:Aged; D047549:Coronary Artery Bypass, Off-Pump / Q000191:economics / Q000706:statistics & numerical data*; D005260:Female; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D007564:Japan; D007902:Length of Stay / Q000706:statistics & numerical data*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications; D057234:Preoperative Period; D012189:Retrospective Studies; D012307:Risk Factors
keywords: CABG; Costs and cost analysis; Health resources; Length of stay; Multi-level analysis