title: Impact of Rabbit Antithymocyte Globulin Dose on Long-term Outcomes in Heart Transplant Patients.
abstract: BACKGROUND
  Optimal dosing strategies have not been established for rabbit antithymocyte globulin (rATG) after heart transplantation, and there is currently wide variability in rATG regimens with respect to both dose and duration.
  
  
  METHODS
  In a retrospective, single-center analysis, 523 patients undergoing heart transplantation during 1996 to 2009 were stratified by cumulative rATG dose: less than 4.5 mg/kg (group A), 4.5 to 7.5 mg/kg (group B) or greater than 7.5 mg/kg (group C).
  
  
  RESULTS
  Survival at 1 year after transplantation was 80% in group A, 90% in group B, and 88% in group C (P = 0.062). Incidence of acute rejection per 1000 patient-years was significantly higher in group A (hazards ratio [HR], 54.8; 95% confidence interval [95% CI], 33.9-83.8) compared to groups B (19.6; 95% CI, 11.4-31.4) and C (23.6; 95% CI, 17.5-31.3). Incidence of severe infection 10 years after transplantation was higher in group C (45%) than groups A (37%) or B (23%) (P < 0.001); cytomegalovirus infection rates were 35%, 20% and 23%, respectively (P = 0.009). Multivariable Cox regression showed an HR of 0.51 (95% CI, 0.25-1.02) for acute rejection with group B versus group A, and 0.54 (95% CI, 0.33-0.88; P = 0.013) for severe infection. The rate of malignancy per 1000 patient-years was higher in groups B (13.85) and C (14.95) than group A (7.83).
  
  
  CONCLUSIONS
  These retrospective data suggest that a cumulative rATG dose of 4.5 to 7.5 mg/kg may offer a better risk-benefit ratio than lower or higher doses, with acceptable rates of infection and posttransplant malignancy. Prospective trials are needed.
authors.affiliation: 1 Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria. 2 Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria. 3 Department of Cardiothoracic and Vascular Anesthesia & Intensive Care Medicine, Medical University of Vienna, Vienna, Austria.
authors.forename: Arezu Z
authors.initials: AZ
authors.lastname: Aliabadi
authors.forename: Martina
authors.initials: M
authors.lastname: Grömmer
authors.forename: Daniela
authors.initials: D
authors.lastname: Dunkler
authors.forename: Farsad
authors.initials: F
authors.lastname: Eskandary
authors.forename: Olivia
authors.initials: O
authors.lastname: Salameh
authors.forename: Johannes
authors.initials: J
authors.lastname: Gökler
authors.forename: Doris
authors.initials: D
authors.lastname: Hutschala
authors.forename: Barbara
authors.initials: B
authors.lastname: Steinlechner
authors.forename: Phillipp
authors.initials: P
authors.lastname: Opfermann
authors.forename: Günther
authors.initials: G
authors.lastname: Laufer
authors.forename: Andreas O
authors.initials: AO
authors.lastname: Zuckermann
mesh_terms: D000961:Antilymphocyte Serum / Q000008:administration & dosage* / Q000009:adverse effects; D001317:Austria; D016009:Chi-Square Distribution; D003141:Communicable Diseases / Q000209:etiology; D004334:Drug Administration Schedule; D005260:Female; D006084:Graft Rejection / Q000276:immunology / Q000517:prevention & control; D006085:Graft Survival / Q000187:drug effects; D016027:Heart Transplantation / Q000009:adverse effects / Q000401:mortality; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage* / Q000009:adverse effects; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009369:Neoplasms / Q000209:etiology; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000961:Antilymphocyte Serum; D007166:Immunosuppressive Agents