Treatment service utilization is expected to increase as expanded insurance coverage removes significant cost barriers to seeking treatment.¹¹ Figure 2 details trends in young adults reporting that they received mental health services in the previous year.¹² Between the beginning of 2005 and the middle of 2010, there was a slight upward trend in rates of receipt of mental health services, with an average of 11.1 percent reporting receiving mental health services in the previous year. Prior to the coverage extension, approximately 10.9 percent of young adults reported receiving mental health services in the previous year. After the coverage extension, the trend in service rates turned sharply upward, with 11.9 percent of young adults reporting receiving services in the last half of 2012.

The increase in service utilization displayed in Figure 2 was primarily driven by newly insured individuals. Figure 3 displays the percentage of young adults receiving mental health services in the previous year by insurance coverage. Receipt of service levels increased among the insured in the post-reform period. Although there appears to be a decline among the uninsured, it is not statistically significant. This suggests that the increase in service utilization was driven by newly insured young adults who previously were unable to get treatment due to lack of insurance coverage.

One objective of the ACA is to address the lack of insurance as a primary cause of delaying or failing to seek care. Extending dependent care coverage to young adults is one of the tools by which the ACA attempts to accomplish this objective. After implementation of the dependent care coverage extension, insurance coverage among the targeted population increased substantially. A potential explanation for this pattern is that mental illness can be a co-morbid condition associated with substance use because individuals with mental health conditions may seek to self-medicate.¹⁵ Since individuals with both mental illness and substance use disorders frequently seek treatment in substance use programs,^{16, 17}  

this result could indicate that uninsured young adults with mental health problems sought treatment in substance use programs prior to the reform, but shifted into mental health service options once they obtained coverage in the post-reform period. Exploring this potential shift provides an opportunity for additional research.  As more individuals receive mental health services, fewer may resort to illicit drugs for relief, leading to less substance use and need for substance use treatment services.¹⁸ In addition to receiving more appropriate treatment, fewer young adults reported the cost of treatment as being a barrier to seeking treatment or services. Finally, costs for treatment or services may have shifted away from the public sector and to private insurance sources.

1. Nicholson, J. L. (2009). Rite of passage? Why young adults become uninsured and how new policies can help, 2009 update. New York, NY: Commonwealth Fund.
2. DeNavas-Walt, C., Proctor, B. D., & Smith, J. C. (2010). Income, poverty, and health insurance coverage in the United States: 2009 (Current Population Reports, /P60–238). Washington, DC: U.S. Census Bureau.
3. Ayanian, J. Z., Weissman, J. S., Schneider, E. C., Ginsburg, J. A., & Zaslavsky, A. M. (2000). Unmet health needs of uninsured adults in the United States. JAMA, 284(16), 2061–2069.
4. Callahan, S. T., & Cooper, W. O. (2005). Uninsurance and health care access among young adults in the United States. Pediatrics, 116(1), 88–95.
5. Weissman, J. S., Gatsonis, C., & Epstein, A. M. (1992). Rates of avoidable hospitalization by insurance status in Massachusetts and Maryland. JAMA, 268(17), 2388–2394.
6. Results are shown for biannual periods to smooth variation in quarterly averages, but still allow for distinction between the pre- and post-implementation in 2010.
7. Insurance coverage is defined as being covered by any type of insurance, public or private, at the time of the interview.
8. Barbaresco, S., Courtemanche, C. J., & Qi, Y. (2014). Impacts of the Affordable Care Act dependent coverage provision on health-related outcomes of young adults (NBER Working Paper No. 20148). Cambridge, MA: National Bureau of Economic Research.
9. Chua, K.-P., & Sommers, B. D. (2014). Changes in health and medical spending among young adults under health reform. JAMA, 311(23), 2437–2439. doi: 10.1001/jama.2014.2202
10. Levine, P. B., McKnight, R., & Heep, S. (2011). How effective are public policies to increase health insurance coverage among young adults? American Economic Journal: Economic Policy, 3(1), 129–156.
11. Manning, W. G., Newhouse, J. P., Duan, N., Keeler, E. B., & Leibowitz, A. (1987). Health insurance and the demand for medical care: evidence from a randomized experiment. The American economic review, 251-277.
12. Mental health services is defined as having received inpatient care or outpatient care or having used prescription medication for problems with emotions, nerves, or mental health. Respondents were not to include treatment for drug or alcohol use.
13. Substance use treatment is defined as receiving treatment at any location for alcohol or illicit drug use in the past year.
14. Source of payment measures are constructed from separate NSDUH variables on source of payment for in-patient mental health treatment, out-patient mental health treatment, and substance use treatment.
15. Bizzarri, J. V., Rucci, P., Sbrana, A., Miniati, M., Raimondi, F., Ravani, L., . . . Massei, G. (2009). Substance use in severe mental illness: self-medication and vulnerability factors. Psychiatry research, 165(1), 88-95.
16. Harris, K. M., & Edlund, M. J. (2005). Use of mental health care and substance abuse treatment among adults with co-occurring disorders. Psychiatric Services, 56(8), 954–959. 
17. Wu, L.-T., Ringwalt, C. L., & Williams, C. E. (2003). Use of substance abuse treatment services by persons with mental health and substance use problems. Psychiatric Services, 54(3), 363–369.
18. Carroll, K. M. (2004). Behavioral therapies for co-occurring substance use and mood disorders. Biological psychiatry, 56(10), 778-784.

Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. (January 2013). The NSDUH Report: Trends in Insurance Coverage and Treatment Utilization by Young Adults. Rockville, MD.