title: Bleeding and first-year mortality following hip fracture surgery and preoperative use of low-dose acetylsalicylic acid: an observational cohort study.
abstract: BACKGROUND
  Hip fracture is associated with high mortality. Cardiovascular disease and other comorbidities requiring long-term anticoagulant medication are common in these mostly elderly patients. The objective of our observational cohort study of patients undergoing surgery for hip fracture was to study the association between preoperative use of low-dose acetylsalicylic acid (LdAA) and intraoperative blood loss, blood transfusion and first-year all-cause mortality.
  
  
  METHODS
  An observational cohort study was conducted on patients with hip fracture (cervical requiring hemiarthroplasty or pertrochanteric or subtrochanteric requiring internal fixation) participating in a randomized trial that found lack of efficacy of a compression bandage in reducing postoperative bleeding. The participants were 255 patients (≥50 years) of whom 118 (46%) were using LdAA (defined as ≤320 mg daily) preoperatively. Bleeding variables in patients with and without LdAA treatment at time of fracture were measured and blood transfusions given were compared using logistic regression. The association between first-year mortality and preoperative use of LdAA was analyzed with Cox regression adjusting for age, sex, type of fracture, baseline renal dysfunction and baseline cardiovascular and/or cerebrovascular disease.
  
  
  RESULTS
  Blood transfusions were given postoperatively to 74 (62.7%) LdAA-treated and 76 (54%) non-treated patients; the adjusted odds ratio was 1.8 (95% CI 1.04 to 3.3). First-year mortality was significantly higher in LdAA-treated patients; the adjusted hazard ratio (HR) was 2.35 (95% CI 1.23 to 4.49). The mortality was also higher with baseline cardiovascular and/or cerebrovascular disease, adjusted HR 2.78 (95% CI 1.31 to 5.88). Patients treated with LdAA preoperatively were significantly more likely to suffer thromboembolic events (5.7% vs. 0.7%, P = 0.03).
  
  
  CONCLUSIONS
  In patients with hip fracture (cervical treated with hemiarthroplasty or pertrochanteric or subtrochanteric treated with internal fixation) preoperative use of low-dose acetylsalicylic acid was associated with significantly increased need for postoperative blood transfusions and significantly higher all-cause mortality during one year after surgery.
authors: Department of Orthopedics, Hässleholm Hospital, SE-281 25 Hässleholm, Sweden. annikakragh@gmail.com
authors: Annika M
authors: AM
authors: Kragh
authors: Markus
authors: M
authors: Waldén
authors: Anna
authors: A
authors: Apelqvist
authors: Philippe
authors: P
authors: Wagner
authors: Isam
authors: I
authors: Atroshi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D016063:Blood Loss, Surgical / Q000401:mortality*; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D006620:Hip Fractures / Q000401:mortality* / Q000601:surgery*; D006801:Humans; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D011300:Preoperative Care; D016032:Randomized Controlled Trials as Topic
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin