title: Hospital variability in use of anticoagulant strategies during acute myocardial infarction treated with an early invasive strategy.
abstract: BACKGROUND
  During a myocardial infarction, no single best approach of systemic anticoagulation is recommended, likely due to a lack of comparative effectiveness studies and trade-offs between treatments.
  
  
  RESULTS
  We investigated the patterns of use and site-level variability in anticoagulant strategies (unfractionated heparin [UFH] only, low-molecular-weight heparin [LMWH] only, UFH+LMWH, any bivalirudin) of 63 796 patients with a principal diagnosis of myocardial infarction treated with an early invasive strategy with percutaneous coronary intervention at 257 hospitals. About half (47%) of patients received UFH only, 6% UFH+LMWH, 7% LMWH only, and 40% bivalirudin. Compared with UFH, the median odds ratio was 2.90 for LMWH+UFH, 4.70 for LMWH only, and 3.09 for bivalirudin, indicating that 2 "identical" patients would have a 3- to 4-fold greater likelihood of being treated with anticoagulants other than UFH at one hospital compared with another. We then categorized hospitals as low- or high-users of LMWH and bivalirudin. Using hierarchical, multivariate regression models, we found that low bivalirudin-using hospitals had higher unadjusted bleeding rates, but the risk-adjusted and anticoagulant-adjusted bleeding rates did not differ across the hospital anticoagulation phenotypes. Risk-standardized mortality and risk-standardized length of stay also did not differ across hospital phenotypes.
  
  
  CONCLUSIONS
  We found substantial site-level variability in the choice of anticoagulants for invasively managed acute myocardial infarction patients, even after accounting for patient factors. No single hospital-use pattern was found to be clinically superior. More studies are needed to determine which patients would derive the greatest benefit from various anticoagulants and to support consistent treatment of patients with the optimal anticoagulant strategy.
authors.affiliation: Saint Luke's Mid America Heart Institute and University of Missouri-Kansas City, Kansas City, MO (S.V.A., J.A.S., M.K.).
authors.forename: Suzanne V
authors.initials: SV
authors.lastname: Arnold
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (S.X.L., J.P.C., K.D., K.M.S., H.M.K.).
authors.forename: Shu-Xia
authors.initials: SX
authors.lastname: Li
authors.affiliation: Duke Clinical Research Institute, Durham, NC (K.P.A., T.Y.W.).
authors.forename: Karen P
authors.initials: KP
authors.lastname: Alexander
authors.affiliation: Saint Luke's Mid America Heart Institute and University of Missouri-Kansas City, Kansas City, MO (S.V.A., J.A.S., M.K.).
authors.forename: John A
authors.initials: JA
authors.lastname: Spertus
authors.affiliation: University of Michigan and the Ann Arbor VA Medical Center, Ann Arbor, MI (B.K.N.).
authors.forename: Brahmajee K
authors.initials: BK
authors.lastname: Nallamothu
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (S.X.L., J.P.C., K.D., K.M.S., H.M.K.) Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (J.P.C., K.D., H.M.K.).
authors.forename: Jeptha P
authors.initials: JP
authors.lastname: Curtis
authors.affiliation: Saint Luke's Mid America Heart Institute and University of Missouri-Kansas City, Kansas City, MO (S.V.A., J.A.S., M.K.).
authors.forename: Mikhail
authors.initials: M
authors.lastname: Kosiborod
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (A.G.).
authors.forename: Aakriti
authors.initials: A
authors.lastname: Gupta
authors.affiliation: Duke Clinical Research Institute, Durham, NC (K.P.A., T.Y.W.).
authors.forename: Tracy Y
authors.initials: TY
authors.lastname: Wang
authors.affiliation: Department of Biostatistics, Yale School of Public Health, New Haven, CT (H.L.).
authors.forename: Haiqun
authors.initials: H
authors.lastname: Lin
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (S.X.L., J.P.C., K.D., K.M.S., H.M.K.) Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (J.P.C., K.D., H.M.K.).
authors.forename: Kumar
authors.initials: K
authors.lastname: Dharmarajan
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (S.X.L., J.P.C., K.D., K.M.S., H.M.K.).
authors.forename: Kelly M
authors.initials: KM
authors.lastname: Strait
authors.affiliation: Premier, Inc, Charlotte, NC (T.J.L., H.M.K.).
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Lowe
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (S.X.L., J.P.C., K.D., K.M.S., H.M.K.) Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (J.P.C., K.D., H.M.K.) Department of Health Policy and Management, Yale School of Public Health, Yale University School of Medicine, New Haven, CT (H.M.K.) Robert Wood Johnson Foundation Clinical Scholars Program, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (H.M.K.) Premier, Inc, Charlotte, NC (T.J.L., H.M.K.).
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D005260:Female; D006493:Heparin / Q000627:therapeutic use; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use; D006629:Hirudins; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000401:mortality / Q000628:therapy; D010446:Peptide Fragments / Q000627:therapeutic use; D062645:Percutaneous Coronary Intervention / Q000379:methods / Q000706:statistics & numerical data; D011994:Recombinant Proteins / Q000627:therapeutic use; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight; D006629:Hirudins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D006493:Heparin; C074619:bivalirudin
keywords: anticoagulation; bleeding; myocardial infarction; variation