Journal of General Internal Medicine

, Volume 34, Issue 12, pp 2740–2748 | Cite as

The Medicare Shared Savings Program and Outcomes for Ischemic Stroke Patients: a Retrospective Cohort Study

  • Brystana G. KaufmanEmail author
  • Emily C. O’Brien
  • Sally C. Stearns
  • Roland Matsouaka
  • G. Mark Holmes
  • Morris Weinberger
  • Paula H. Song
  • Lee H. Schwamm
  • Eric E. Smith
  • Gregg C. Fonarow
  • Ying Xian
Original Research



Post-stroke care delivery may be affected by provider participation in Medicare Shared Savings Program (MSSP) Accountable Care Organizations (ACOs) through systematic changes to discharge planning, care coordination, and transitional care.


To evaluate the association of MSSP with patient outcomes in the year following hospitalization for ischemic stroke.


Retrospective cohort


Get With The Guidelines (GWTG)–Stroke (2010–2014)


Hospitalizations for mild to moderate incident ischemic stroke were linked with Medicare claims for fee-for-service beneficiaries ≥ 65 years (N = 251,605).

Main Measures

Outcomes included discharge to home, 30-day all-cause readmission, length of index hospital stay, days in the community (home-time) at 1 year, and 1-year recurrent stroke and mortality. A difference-in-differences design was used to compare outcomes before and after hospital MSSP implementation for patients (1) discharged from hospitals that chose to participate versus not participate in MSSP or (2) assigned to an MSSP ACO versus not or both. Unique estimates for 2013 and 2014 ACOs were generated.

Key Results

For hospitals joining MSSP in 2013 or 2014, the probability of discharge to home decreased by 2.57 (95% confidence intervals (CI) = − 4.43, − 0.71) percentage points (pp) and 1.84 pp (CI = − 3.31, − 0.37), respectively, among beneficiaries not assigned to an MSSP ACO. Among discharges from hospitals joining MSSP in 2013, beneficiary ACO alignment versus not was associated with increased home discharge, reduced length of stay, and increased home-time. For patients discharged from hospitals joining MSSP in 2014, ACO alignment was not associated with changes in utilization. No association between MSSP and recurrent stroke or mortality was observed.


Among patients with mild to moderate ischemic stroke, meaningful reductions in acute care utilization were observed only for ACO-aligned beneficiaries who were also discharged from a hospital initiating MSSP in 2013. Only 1 year of data was available for the 2014 MSSP cohort, and these early results suggest further study is warranted.




health policy health services research Medicare stroke utilization outcomes 



Internal funding for this study was provided by the Duke Clinical Research Institute. The GWTG–Stroke program is currently supported in part by a charitable contribution from Bristol-Myers Squibb/Sanofi Pharmaceutical Partnership and the American Heart Association Pharmaceutical Roundtable. GWTG–Stroke has been funded in the past through support from Boehringer-Ingelheim and Merck.

Compliance with Ethical Standards

Conflict of Interest

ECO: Research grants from BMS, Novartis, Janssen, and GSK

GCF: Research Patient Centered Outcomes Research Institute, Consultant to Janssen

YX: Research funding from the American Heart Association, Daiichi Sankyo, Janssen Pharmaceuticals, and Genentech. Honorarium from Brain Canada

All remaining authors declare that they do not have a conflict of interest.

Supplementary material

11606_2019_5283_MOESM1_ESM.docx (74 kb)
ESM 1 (DOCX 73 kb)


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Copyright information

© Society of General Internal Medicine 2019

Authors and Affiliations

  • Brystana G. Kaufman
    • 1
    • 2
    Email author
  • Emily C. O’Brien
    • 2
  • Sally C. Stearns
    • 1
    • 3
  • Roland Matsouaka
    • 4
  • G. Mark Holmes
    • 1
    • 3
  • Morris Weinberger
    • 1
  • Paula H. Song
    • 1
    • 3
  • Lee H. Schwamm
    • 5
    • 6
  • Eric E. Smith
    • 7
  • Gregg C. Fonarow
    • 8
  • Ying Xian
    • 4
  1. 1.Department of Health Policy and ManagementUniversity of North Carolina at Chapel HillChapel HillUSA
  2. 2.Department of Population Health Sciences Duke UniversityDurhamUSA
  3. 3.The Cecil G. Sheps Center for Health Services ResearchUniversity of North Carolina at Chapel HillChapel HillUSA
  4. 4.Duke Clinical Research InstituteDurhamUSA
  5. 5.NeurologyMassachusetts General HospitalBostonUSA
  6. 6.Harvard Medical SchoolBostonUSA
  7. 7.Department of Clinical Neurosciences, Cumming School of MedicineUniversity of CalgaryCalgaryCanada
  8. 8.CardiologyDavid Geffen School of Medicine at UCLALos AngelesUSA

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