Medicare ACOs Add 106

"By far the biggest reason for organizations not getting a contract from CMS was the statute that says that ACOs have to demonstrate they can serve a population of 5,000 beneficiaries," Blum says. 

"To demonstrate true cost savings beyond random variation there has to be a sizeable population, so Congress determined the population was 5,000 or more. We are bound to follow that."

The next application period for the shared-savings program that begins in January 2014 is summer 2013.

Also this week, HHS is crediting the PPACA with reducing the growth rate of Medicare spending. According to a new report from HHS, Medicare spending growth per beneficiary hit "historic lows," averaging 1.9% from 2010 to 2012, which is more than one percentage point lower than the average annual growth of 3.2% per capita for the Gross Domestic Product.

Projections by both the Office of the Actuary at CMS and by the Congressional Budget Office estimate that Medicare spending per beneficiary will grow at approximately the rate of growth of the economy for the next decade, breaking a decades-old pattern of spending growth outstripping economic growth, the report said.