title: Regional associations between Medicare Advantage penetration and administrative claims-based measures of hospital outcomes.
abstract: BACKGROUND
  Risk-standardized measures of hospital outcomes reported by the Centers for Medicare and Medicaid Services include Medicare fee-for-service (FFS) patients and exclude Medicare Advantage (MA) patients due to data availability. MA penetration varies greatly nationwide and seems to be associated with increased FFS population risk. Whether variation in MA penetration affects the performance on the Centers for Medicare and Medicaid Service measures is unknown.
  
  
  OBJECTIVE
  To determine whether the MA penetration rate is associated with outcomes measures based on FFS patients.
  
  
  METHODS
  In this retrospective study, 2008 MA penetration was estimated at the Hospital Referral Region (HRR) level. Risk-standardized mortality rates and risk-standardized readmission rates for heart failure, acute myocardial infarction, and pneumonia from 2006 to 2008 were estimated among HRRs, along with several markers of FFS population risk. Weighted linear regression was used to test the association between each of these variables and MA penetration among HRRs.
  
  
  RESULTS
  Among 304 HRRs, MA penetration varied greatly (median, 17.0%; range, 2.1%-56.6%). Although MA penetration was significantly (P<0.05) associated with 5 of the 6 markers of FFS population risk, MA penetration was insignificantly (P≥0.05) associated with 5 of 6 hospital outcome measures.
  
  
  CONCLUSIONS
  Risk-standardized mortality rates and risk-standardized readmission rates for heart failure, acute myocardial infarction, and pneumonia do not seem to differ systematically with MA penetration, lending support to the widespread use of these measures even in areas of high MA penetration.
authors.affiliation: Yale University School of Medicine, New Haven, CT 06510, USA.
authors.forename: Vivek T
authors.initials: VT
authors.lastname: Kulkarni
authors.forename: Sachin J
authors.initials: SJ
authors.lastname: Shah
authors.forename: Susannah M
authors.initials: SM
authors.lastname: Bernheim
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Wang
authors.forename: Sharon-Lise T
authors.initials: SL
authors.lastname: Normand
authors.forename: Lein F
authors.initials: LF
authors.lastname: Han
authors.forename: Michael T
authors.initials: MT
authors.lastname: Rapp
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Drye
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D018588:Fee-for-Service Plans / Q000706:statistics & numerical data; D006333:Heart Failure / Q000401:mortality; D017052:Hospital Mortality; D006761:Hospitals / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D007345:Insurance Claim Review / Q000706:statistics & numerical data*; D020398:Medicare Part C / Q000706:statistics & numerical data*; D009203:Myocardial Infarction / Q000401:mortality; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D010359:Patient Readmission / Q000706:statistics & numerical data; D011014:Pneumonia / Q000401:mortality; D019984:Quality Indicators, Health Care / Q000706:statistics & numerical data; D012111:Residence Characteristics / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States