Abstract
BACKGROUND AND OBJECTIVES: Despite representing 1% of the population, beneficiaries on long-term dialysis account for over 7% of Medicare's fee-for-service spending. Because of their focus on care coordination, Accountable Care Organizations may be an effective model to reduce spending inefficiencies for this population. We analyzed Medicare data to examine time trends in long-term dialysis beneficiary alignment to Accountable Care Organizations and differences in spending for those who were Accountable Care Organization aligned versus nonaligned. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In this retrospective cohort study, beneficiaries on long-term dialysis between 2009 and 2016 were identified using a 20% random sample of Medicare beneficiaries. Trends in alignment to an Accountable Care Organization were compared with alignment of the general Medicare population from 2012 to 2016. Using an interrupted time series approach, we examined the association between Accountable Care Organization alignment and the primary outcome of total spending for long-term dialysis beneficiaries from prior to Accountable Care Organization implementation (2009-2011) through implementation of the Comprehensive ESRD Care model in October 2015. We fit linear regression models with generalized estimating equations to adjust for patient characteristics. RESULTS: During the study period, 135,152 beneficiaries on long-term dialysis were identified. The percentage of long-term dialysis beneficiaries aligned to an Accountable Care Organization increased from 6% to 23% from 2012 to 2016. In the time series analysis, spending on Accountable Care Organization-aligned beneficiaries was $143 (95% confidence interval, $5 to $282) less per beneficiary-quarter than spending for nonaligned beneficiaries. In analyses stratified by whether beneficiaries received care from a primary care physician, savings by Accountable Care Organization-aligned beneficiaries were limited to those with care by a primary care physician ($235; 95% confidence interval, $73 to $397). CONCLUSIONS: There was a substantial increase in the percentage of long-term dialysis beneficiaries aligned to an Accountable Care Organization from 2012 to 2016. Moreover, in adjusted models, Accountable Care Organization alignment was associated with modest cost savings among long-term dialysis beneficiaries with care by a primary care physician.