Post-Acute Care Use Associated with Medicare Shared Savings Program and Disparities.

OBJECTIVES: Medicare Shared Savings Program (MSSP) was implemented in 2012, but the impact of the MSSP on institutional post-acute care (PAC) use, and by race/ethnicity and payer status is less studied. We studied the impact of hospital participation in the MSSP on institutional PAC use and variations by race/ethnicity and payer status among 3 Medicare patient groups: ischemic stroke, hip fracture, and elective total joint arthroplasty (TJA). DESIGN: A retrospective analysis of 2010-2016 Medicare Provider Analysis and Review files. SETTING AND PARTICIPANTS: Medicare fee-for-service patients originally admitted for ischemic stroke, hip fracture, or elective TJA in MSSP-participating hospitals or nonparticipating hospitals. METHODS: Patient-level linear probability models with difference-in-differences approach were used to compare the changes in institutional PAC use in MSSP-participating hospitals with nonparticipating hospitals as well as to compare the changes in differences by race/ethnicity and payer status in institutional PAC use over time. RESULTS: Hospital participation in MSSP was significantly associated with increased institutional PAC use for the ischemic stroke cohort by 1.5 percentage points [95% confidence interval (CI) 0.00-0.3, P < .05] compared with non-MSSP participating hospitals. Regarding variations by race/ethnicity and payer status, for the elective TJA patients, racial minority patients in MSSP-participating hospitals had 3.8 percentage points greater (95% CI 0.01-0.06, P < .01) in institutional PAC use than white patients. Also, for ischemic stroke cohort, dual-eligible patients in MSSP-participating hospitals had 2.0 percentage points greater (95% CI 0.00-0.04, P < .10) in institutional PAC use than Medicare-only patients. CONCLUSIONS AND IMPLICATIONS: This study found that hospital participation in the MSSP was associated with slightly increased institutional PAC use for ischemic stroke Medicare patients. Also, compared to non-MSSP participating hospitals, MSSP-participating hospitals were more likely to discharge racial minority patients for elective TJA and dual-eligible patients for ischemic stroke to institutional PAC.