title: Application of a methicillin-resistant Staphylococcus aureus risk score for community-onset pneumonia patients and outcomes with initial treatment.
abstract: BACKGROUND
  Community-onset (CO) methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is an evolving problem, and there is a great need for a reliable method to assess MRSA risk at hospital admission. A new MRSA prediction score classifies CO-pneumonia patients into low, medium, and high-risk groups based on objective criteria available at baseline. Our objective was to assess the effect of initial MRSA therapy on mortality in these three risk groups.
  
  
  METHODS
  We conducted a retrospective cohort study using data from the Veterans Health Administration (VHA). Patients were included if they were hospitalized with pneumonia and received antibiotics within the first 48 h of admission. They were stratified into MRSA therapy and no MRSA therapy treatment arms based on antibiotics received in the first 48 h. Multivariable logistic regression was used to adjust for potential confounders.
  
  
  RESULTS
  A total of 80,330 patients met inclusion criteria, of which 36% received MRSA therapy and 64% did not receive MRSA therapy. The majority of patients were classified as either low (51%) or medium (47%) risk, with only 2% classified as high-risk. Multivariable logistic regression analysis demonstrated that initial MRSA therapy was associated with a lower 30-day mortality in the high-risk group (adjusted odds ratio 0.57; 95% confidence interval 0.42-0.77). Initial MRSA therapy was not beneficial in the low or medium-risk groups.
  
  
  CONCLUSIONS
  This study demonstrated improved survival with initial MRSA therapy in high-risk CO-pneumonia patients. The MRSA risk score might help spare MRSA therapy for only those patients who are likely to benefit.
authors.affiliation: St. Louis College of Pharmacy, St. Louis, MO, USA. besu.teshome@stlcop.edu.|Pharmacotherapy Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. besu.teshome@stlcop.edu.|Pharmacotherapy Education and Research Center, School of Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., MSC-6220, San Antonio, TX, 78229, USA. besu.teshome@stlcop.edu.
authors.forename: Besu F
authors.initials: BF
authors.lastname: Teshome
authors.affiliation: Pharmacotherapy Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. leeg3@uthscsa.edu.|Pharmacotherapy Education and Research Center, School of Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., MSC-6220, San Antonio, TX, 78229, USA. leeg3@uthscsa.edu.
authors.forename: Grace C
authors.initials: GC
authors.lastname: Lee
authors.affiliation: Pharmacotherapy Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. kdaniels46@utexas.edu.|Pharmacotherapy Education and Research Center, School of Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., MSC-6220, San Antonio, TX, 78229, USA. kdaniels46@utexas.edu.
authors.forename: Kelly R
authors.initials: KR
authors.lastname: Reveles
authors.affiliation: Feik School of Pharmacy, University of the Incarnate Word, San Antonio, TX, USA. attridge@uiwtx.edu.|South Texas Veterans Health Care System, San Antonio, TX, USA. attridge@uiwtx.edu.
authors.forename: Russell T
authors.initials: RT
authors.lastname: Attridge
authors.affiliation: Pharmacotherapy Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. koeller@uthscsa.edu.|Pharmacotherapy Education and Research Center, School of Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., MSC-6220, San Antonio, TX, 78229, USA. koeller@uthscsa.edu.
authors.forename: Jim
authors.initials: J
authors.lastname: Koeller
authors.affiliation: Department of Epidemiology and Biostatistics, University of Texas Health Science Center, San Antonio, TX, USA. wangc3@uthscsa.edu.
authors.forename: Chen-pin
authors.initials: CP
authors.lastname: Wang
authors.affiliation: The VA North Texas Health Care System, Dallas, TX, USA. Eric.Mortensen@utsouthwestern.edu.|The University of Texas Southwestern Medical Center, Dallas, TX, USA. Eric.Mortensen@utsouthwestern.edu.
authors.forename: Eric M
authors.initials: EM
authors.lastname: Mortensen
authors.affiliation: Pharmacotherapy Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. freic@uthscsa.edu.|Pharmacotherapy Education and Research Center, School of Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., MSC-6220, San Antonio, TX, 78229, USA. freic@uthscsa.edu.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Frei
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D016017:Odds Ratio; D011014:Pneumonia / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D012189:Retrospective Studies; D012306:Risk; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents