If required by CMS to take on downside risk, nearly half would leave the program, according to data from the National Association of ACOs.
A survey of ACOs finds more than half of the respondents would leave the Medicare Shared Savings Program (MSSP) if they were not eligible for the 5% Advanced Alternative Payment Model (APM) bonus.
The bonus is a provision of the proposed rule for the Medicare Access and CHIP Reauthorization Act (MACRA) released in April.
The National Association of ACOs (NAACOS) reports in its spring survey that 56% of 144 ACOs surveyed in 40 states would be very unlikely or somewhat unlikely to stay in the MSSP.
Eleven percent said they were unsure, 32% said they were very likely or somewhat likely to stay, and 2% were ineligible to stay in the MSSP Track 1 program beyond their current agreement, based on CMS policy.
Of multi-ACO organizations, 42% are very or somewhat unlikely to stay in MSSP, 2% are unsure, and 56% are very or somewhat likely to stay in MSSP, the survey reports.
Slightly more than half (51%) of the ACOs described their ongoing operational costs as "very significant" and only 6% described these costs as "nominal or negligible".
If required by the Centers for Medicare and Medicaid Services, to take on downside risk, 43% of ACOs surveyed said they would leave the program and 33% would stay, NACCOS reports.
The majority (84%) of respondents said they would be ready for downside risk within the next six years, with 44% of those ready as soon as one to three years.
NAACOS says it hopes that these findings will spark conversations about the investment, risk, and policy challenges facing ACOs and healthcare systems in today's rapidly evolving environment.
"As the survey findings demonstrate, ACOs are investing a significant amount and are maturing in their readiness to take on downside risk, surprisingly fast considering how few years the program has been in place," the report concludes.