Medicare ACOs Have Only Limited Effect on Care of Mental Illness

Medicare accountable care organizations (ACOs) have either not yet focused on mental illness or have been, for the most part, unsuccessful in early efforts to improve their management of it, according to a recent study of ACO contracts in the Medicare Shared Savings Program and the Pioneer model for beneficiaries with mental illness. The study appears in the August 2016 issue of Health Affairs

Using Medicare claims and enrollment data for a random 20% sample of fee-for-service beneficiaries for 2008- 2013 for adults with at least one acute mental health hospitalization or at least 2 outpatient mental health diagnoses at least 7 days apart,

Alisa B. Busch, MD, assistant professor of psychiatry and healthcare policy at Harvard Medical School, and colleagues compared ACOs with local non-ACO providers. (The study did not assess ACO contracts on beneficiaries with substance use disorders because claims with these codes are not allowed because of confidentiality regulations.) For each year in the study’s span, the sample included all living members of the previous year’s 20% sample plus a 20% sample of newly eligible beneficiaries. The researchers created diagnostic indicators for beneficiaries in the following categories: schizophrenia, bipolar disorder, other paranoid states, and nonorganic psychoses; major depressive disorder, other depression diagnoses, and anxiety.

The investigators examined the effects of Medicare ACO contracts on inpatient and outpatient mental health spending, utilization, and several measures of mental health care quality for beneficiaries with mental illness. They analyzed annual Medicare spending for mental health care by setting (inpatient, emergency department, [ED] and outpatient), and annual utilization of the following services related to mental illness: inpatient admissions, ED visits, office visits or medication management, outpatient psychotherapy, and partial hospitalizations.

The study also assessed whether there were differences between Pioneer and Medicare Shared Savings Program ACOs in the inclusion of mental health professionals in their ACO contracts. Additionally, the investigators analyzed 3 claims-based quality measures: for beneficiaries with a mental health admission during any given year, the proportions of admissions that were followed by a mental health readmission within 30 days of discharge and that had outpatient mental healthcare follow-up within 7 days of discharge, and having a diagnosis of depressive disorder.

The study concludes that Pioneer contracts were associated with lower spending on mental health admissions in the first year of the contract, but in the second year of the contract that association was attenuated. Otherwise, ACO contracts were associated with no changes in mental health spending or readmissions, outpatient follow-up after mental health admissions, rates of depression diagnosis, or mental health status.

“In both the Pioneer model and the Medicare Shared Savings Program, we found no differential changes in three claims-based quality measures or in patient-reported mental health status,” the study concluded.

The authors believe that if ACOs hope to achieve lasting improvements in care for people with mental illness, the organizations need to implement strategies that are more effective than those used in the early years of the program.