title: Allogeneic blood transfusion and prognosis following total hip replacement: a population-based follow up study.
abstract: BACKGROUND
  Allogeneic red blood cell transfusion is frequently used in total hip replacement surgery (THR). However, data on the prognosis of transfused patients are sparse. In this study we compared the risk of complications following THR in transfused and non-transfused patients.
  
  
  METHODS
  A population-based follow-up study was performed using data from medical databases in Denmark. We identified 28,087 primary THR procedures performed from 1999 to 2007, from which we computed a propensity score for red blood cell transfusion based on detailed data on patient-, procedure-, and hospital-related characteristics. We were able to match 2,254 transfused with 2,254 non-transfused THR patients using the propensity score.
  
  
  RESULTS
  Of the 28,087 THR patients, 9,063 (32.3%) received at least one red blood cell transfusion within 8 days of surgery. Transfused patients had higher 90-day mortality compared with matched non-transfused patients: the adjusted OR was 2.2 (95% confidence interval (CI): 1.2-3.8). Blood transfusion was also associated with increased odds of pneumonia (OR 2.1; CI: 1.2-3.8), whereas the associations with cardiovascular or cerebrovascular events (OR 1.4; CI: 0.9-2.2) and venous thromboembolism (OR 1.2; CI: 0.7-2.1) did not reach statistical significance. The adjusted OR of reoperation due to infection was 0.6 (CI: 0.1-2.9).
  
  
  CONCLUSIONS
  Red blood cell transfusion was associated with an adverse prognosis following primary THR, in particular with increased odds of death and pneumonia. Although the odds estimates may partly reflect unmeasured bias due to blood loss, they indicate the need for careful assessment of the risk versus benefit of transfusion even in relation to routine THR procedures.
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200 Aarhus N, Denmark. abp@dce.au.dk
authors.forename: Alma B
authors.initials: AB
authors.lastname: Pedersen
authors.forename: Frank
authors.initials: F
authors.lastname: Mehnert
authors.forename: Soren
authors.initials: S
authors.lastname: Overgaard
authors.forename: Soren P
authors.initials: SP
authors.lastname: Johnsen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D001803:Blood Transfusion / Q000379:methods / Q000706:statistics & numerical data; D002648:Child; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care; D011014:Pneumonia / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology; D019106:Postoperative Hemorrhage / Q000628:therapy*; D011379:Prognosis; D012307:Risk Factors; D012309:Risk-Taking; D065227:Transfusion Reaction; D014184:Transplantation, Homologous; D016896:Treatment Outcome; D055815:Young Adult