Just 66 accountable care organizations joined the Medicare Shared Savings Program for the July 1 start date, which is about half the number of ACOs that joined in 2018.
There are now 518 ACOs in the Medicare Shared Savings Program compared with 561 last year. Of those ACOs, 41 are entirely new to the program and 25 are re-entering after a period of not participating.
Previous years saw much higher enrollment figures, according to the National Association of ACOs. In 2018, 124 new ACOs joined the program and in 2017, 99 new ACOs entered it.
In a blog post published Wednesday in Health Affairs, CMS Administrator Seema Verma announced the newest enrollment figures in the Medicare ACO program since the agency overhauled the program late last year. Medicare ACOs will now be required to take on downside risk sooner in the program, which analysts said would likely lead to participation drops. The CMS made the changes as ACOs continued to hold off taking on downside risk years into the program.
"This slowing growth will shrink the pool of future, risk-taking ACOs, which CMS should concern itself with," Clif Gaus, CEO of the National Association of ACOs, said in a prepared statement.
Although participation in the program overall declined, more ACOs are taking on risk compared with previous years. Verma said 48% of the ACOs starting July 1 are taking on downside risk. This is much higher risk-taking than 2018, when only 18% of the ACOs were in a downside-risk-based contract.
Additionally, 45% of those ACOs are taking on enough risk to qualify as an Advanced Alternative Payment Model, which means the physicians will be eligible for a 5% Medicare payment bonus and be exempt from the Merit-based Incentive Payment System program, known as MIPS.
Verma said, "This is projected to lead to more savings for beneficiaries and taxpayers, and provide stronger incentives for ACOs to coordinate care and improve quality for patients."
But an analysis of the new enrollment figures shows most of the ACOs in downside-risk contracts aren't among the new ones joining. Instead, 43 of the ACOs new to the program are in Level A or B of the program's basic track; those two levels don't include downside risk.
Additionally, of the 113 ACOs in tracks that have downside risk and qualify as an Advanced Alternative Payment Model, just 20 are among the new ACOs.