Psychiatric Patients Have Greater Usage of Mental Health Services With Insurance Plans That Provide Equal Cost Sharing

Following a psychiatric discharge, Medicare patients in insurance plans that provide equal cost sharing for mental health services have higher use of those services compared to patients in plans that require greater cost sharing, according to a study in the December 24/31 issue of JAMA.


Health insurers in the United States have historically treated mental illness as distinct from all other medical illnesses by imposing higher out-of-pocket costs and instituting special restrictions for the use of mental health services. “Advocates for parity [equal cost sharing] argue that restricted mental health coverage unfairly discriminates against individuals with mental illness. … Because less than half of individuals with mental illness receive care for their condition, parity in insurance coverage could improve the use of effective treatment,” the authors write. “Timely outpatient mental health care following a psychiatric hospitalization is associated with fewer readmissions, more effective transitions to community-based services, and improved mental health outcomes.”


In 2008, the U.S. Congress enacted legislation requiring parity in insurance coverage for mental health services in group health plans covering more than 50 employees and Medicare Part B beginning in 2010. Few studies have assessed the effect of parity on the access and quality of mental health care, according to background information in the article.


Amal N. Trivedi, M.D., M.P.H., of the Warren Alpert Medical School at Brown University, Providence, R.I., and colleagues examined the relation between parity in outpatient cost sharing and whether enrollees had an outpatient mental health visit within 7 and 30 days following a hospitalization for mental illness. The researchers reviewed cost-sharing requirements for outpatient mental and general medical services for 302 Medicare health plans from 2001 to 2006. Among 43,892 enrollees in 173 health plans who were hospitalized for a mental illness, the relation of parity in cost sharing and receipt of timely outpatient mental health care after discharge was determined using cross-sectional analyses of all Medicare plans and longitudinal analyses of 10 plans that discontinued parity compared with 10 matched control plans that maintained parity.


More than three-quarters of Medicare plans, representing 79 percent of Medicare enrollees, required greater cost sharing for mental health care compared with primary or specialty care. The researchers found that individuals in full-parity plans were more likely to visit a mental health practitioner within 7 and 30 days after a hospitalization compared with enrollees in Medicare plans with intermediate or no parity. For example, co-payments that were $14 greater in plans without parity compared with full-parity plans were associated with an 11 percentage point lower rate of follow-up after a psychiatric hospitalization.


The researchers also examined the association between insurance parity and follow-up visits for individuals from areas of lower income and education. Individuals in the lowest quarter of area-level income had a 7-day follow-up rate that was 14.7 percentage points lower in plans with no parity vs. plans with full parity, and for individuals in the lowest quarter of area-level education, the 30-day follow-up rate was 18.3 percentage points lower in plans with no parity vs. plans with full parity.

Rates of follow-up visits within 30 days decreased by 7.7 percentage points in plans that discontinued parity and increased by 7.5 percentage points among control plans that maintained parity.


“Most Medicare health plans, like most commercial health plans, have unequal coverage for mental health services compared with other medical services. Enrollees in plans without parity in cost sharing are less likely to receive timely outpatient care following a hospitalization for mental illness. While prior studies have shown that adoption of mental health parity does not increase mental health spending, parity legislation that equalizes cost sharing for mental health and primary care may increase the use of clinically appropriate mental health services,” the authors conclude.


JAMA. 2008;300[24]:2879-2885.