The analysis of healthcare spending by Anthem Blue Cross and HealthCare Partners in California offers one of the first large documented examples of how accountable care organizations (ACOs) may trim costs in the commercial PPO population.

Unlike HMOs, PPO patients can see any provider, but this did not seem to hinder HealthCare Partners in holding down costs, even though the medical group couldn’t force patients to only stay only within the ACO for care.

According to Anthem and HealthCare Partners, when compared to similar PPO patients who were not part of an ACO, the ACO patients had a risk-adjusted 18 percent fewer hospital inpatient days and 4 percent fewer inpatient admits. They also had 4 percent fewer outpatient visits (which included emergency room visits), 4 percent fewer radiology procedures, 4 percent fewer laboratory tests, and 2 percent fewer professional visits. Over a six-month period, this meant $4.7 million less in healthcare spending for the ACO group than the comparison non-ACO group, Anthem and HealthCare Partners concluded.

In addition, the ACO group achieved better quality measures, they said, as measured by the Healthcare Effectiveness Data and Information Set (HEDIS) metric for use of preventive health screenings and acute and chronic disease management.

“HealthCare Partners and Anthem have proven that the ACO model in the commercial space can be successful if focused on improving quality outcomes and increasing patient satisfaction while reducing costs,” said Tom Paulsen, M.D., executive medical director, HealthCare Partners in the press release.

HealthCare Partners Medical Group is one of Anthem’s 14 ACOs in California. It serves Southern California patients and the study included 55,000 Anthem PPO enrollees. The medical group is managed and operated by HealthCare Partners, LLC, a subsidiary of DaVita HealthCare Partners. HealthCare Partners Medical Group is now two years into the ACO model.

A couple of factors not mentioned in the press release but which may have influenced Anthem and HealthCare Partner’s ability to so quickly realize savings are a focus on care coordination and sharing data. Michael Belman, M.D., Anthem's medical director, told the L.A. Times that Anthem pays HealthCare Partners from some care coordination services like emailing and calling patients because it ultimately lowers overall costs. In addition, it shares data on PPO patients to help HealthCare Partners better manage this patient population.

"We would like well-established medical groups to take their enormous capacity and expertise to turn this 180 degrees and shine a light on the relatively unmanaged, uncoordinated care that may be present in the PPO world," he told the Times. "There is a tremendous opportunity here.”