Mass. Study: Savings 'Spillover' From Blue Cross Global Plan

Health wonk alert: If you can define an ACO (Accountable Care Organization) and know a little bit about the AQC (a pioneering global payment experiment by Blue Cross Blue Shield of Massachusetts), then read on.

There's evidence from a study just out in JAMA that when doctors change the way they care for one group of patients (as with the AQC), there is a spillover benefit for other patients (in this case, Medicare).

Dr. Michael McWilliams says doctors who were part of the AQC, but weren't being paid through a global budget for their Medicare patients, still cut Medicare spending by 3.4%.

He says the savings "would suggest that providers aren't just targeting changing, but are changing their processes of care in a more systemic way such that the value of care they deliver to all patients is higher."

That claim is harder to prove if you look at the quality of care Medicare members received as compared to patients in the Blue Cross ACQ.  McWilliams found some spillover to quality improvements.  Doctors provided fewer unnecessary MRIs for back pain and more consistent cholesterol testing.  But other "quality measures" such as reducing readmissions or preventable hospitalizations did not migrate from Blue Cross to Medicare members.

In Massachusetts, these findings may not have much practical effect for patients.  Most residents on Medicare have moved into one of the Pioneer ACOs, where doctors have incentives to spend money more wisely and boost preventive care. But it's an interesting finding given that a lot of doctors talk about feeling '"schizophrenic" when they have to manage some patients who are on global budgets and others who are not, who are still fee for service.

For the nation, McWilliams says the findings show that contracts like the AQC have the "potential to foster systemic changes in care delivery." From the press release on the study:

Michael McWilliams, M.D., Ph.D., of Harvard Medical School, Boston, and colleagues conducted a study to examine whether the Blue Cross Blue Shield (BCBS) of Massachusetts' Alternative Quality Contract (AQC), an early commercial ACO initiative associated with reduced spending and improved quality for BCBS enrollees, was also associated with changes in spending and quality for Medicare beneficiaries, who were not covered by the AQC. The study included comparisons from 2007-2010 of elderly fee-for-service Medicare beneficiaries in Massachusetts served by 11 provider organizations entering the AQC in 2009 or 2010 (intervention group) vs. beneficiaries served by other providers (control group). The researchers estimated changes in spending and quality for the intervention group in the first and second years of exposure to the AQC relative to concurrent changes for the control group. The primary outcome was total quarterly medical spending per beneficiary.

Secondary outcomes included spending by setting and type of service, 5 process measures of quality, potentially avoidable hospitalizations, and 30-day readmissions.

The researchers found that differential changes in sociodemographic and clinical characteristics were small for the intervention group relative to the control group, and none was statistically significant, suggesting that the findings were not due to changes in patient case mix. Adjusted total quarterly spending was $150 higher for the intervention group than for the control group, and spending trends were similar before AQC incentives were implemented for participating organizations. "In year 2 of the intervention group's exposure to the AQC, the spending difference between the intervention and control groups was reduced to $51, constituting a significant differential change of -$99 or a 3.4 percent savings relative to an expected quarterly mean of $2,895. Savings in year 1 were not statistically significant."

Savings in year 2 were explained largely by differential changes in outpatient care (-$73) and included significant differential changes in spending on office visits, emergency department visits, minor procedures, imaging, and laboratory tests. Estimated savings in year 2 spending on outpatient care for the intervention group were greater among beneficiaries with 5 or more conditions (-$125) than among those with fewer conditions (-$61).

"Annual rates of low-density lipoprotein cholesterol testing differentially improved for beneficiaries with diabetes in the intervention group by 3.1 percentage points and for those with cardiovascular disease by 2.5 percentage points, but performance on other quality measures did not differentially change," the authors write.

Readers with a taste for hard-core health policy: Thoughts?