The study developed information on behavioral health spending and utilization that can be used to anticipate, evaluate, and interpret changes in health care spending following implementation of the Mental Health Parity and Addiction Equity Act (MHPAEA).
Data were from the Thomson Reuters' MarketScan database of insurance claims between 2001 and 2009 from large group health plans sponsored by self-insured employers. Annual rates in growth of total health spending and behavioral health spending and the contribution of behavioral health spending to growth in spending for all diseases were determined. Separate analyses examined behavioral health and total health spending by 135 employers in 2008 and 2009, and simulations were conducted to determine how increases in use of mental health services after implementation of parity would affect overall health care expenditures.
Across the nine years examined, behavioral health expenditures contributed .3%, on average, to the total rate of growth in all health expenditures, a contribution that fell to .1%, on average, when prescription drugs were excluded. About 2% of employers experienced an increased contribution by behavioral health spending of more than 1%. More than 90% of enrollees used well below the maximum 30 inpatient days or outpatient visits typical of health insurance plans before parity. Simulations indicated that even large increases in utilization would increase total health care expenditures by less than 1%.
The MHPAEA is unlikely to have a large effect on the growth rate of employers' health care expenditures. The data provide baseline information to further evaluate the implementation effect of the MHPAEA. (Psychiatric Services 63:313–318, 2012; doi: 10.1176/appi.ps.201100312)