Impact of High Deductible Health Plans on Patients With Bipolar Disorder

Bipolar disorder is a severe mental illness affecting about 3% of the U.S. population that causes personal suffering, morbidity, and premature mortality. Continuous access to medications, close monitoring, and other psychiatric care are crucial for avoiding complications of bipolar disorder such as relapse, hospitalization, and suicide. To control rising costs, payers and employers are increasingly adopting high-deductible health plans (HDHPs) with very high out-of-pocket payments. Federally-defined Health Savings Account HDHPs require full cost-sharing for all non-preventive services, including medications and specialist visits; family deductibles for HSA-HDHPs range from $2,500 to $12,700. Enrollment in HDHPs quadrupled nationally between 2006 and 2013 to 38% of all workers. Analysts expect further explosive growth because of continued health care cost pressure on families and employers. Well-informed patients in HDHPs might reduce use of unnecessary services and more expensive treatment options. However, patients might also choose to forego needed care. There is very little evidence on how particularly vulnerable patients such as those with bipolar disorder or other chronic mental illnesses fare when forced to make complex choices about spending for care under HDHPs. Given their rapid escalation, there is an urgent need to understand how vulnerable patients change their patterns of care and medication adherence under HDHPs. We will compare patients with three types of insurance: traditional plans with low or no deductible; HDHPs in which chronic medications are paid fully out-of-pocket until the deductible is met; and HDHPs where medications are subject to the same co-pays as in traditional plans.

OBJECTIVES:

Using ten years of data from the largest U.S. commercial health insurer (~70 million members in all 50 states), we will assess the impact of HDHPs on key outcomes for patients with bipolar disorder experiencing employer-mandated shifts from traditional insurance to HDHPs. Our specific aims are to evaluate: (1) changes in medication adherence, and in intensity and quality of other health care; (2) changes in adverse events; and, (3) changes in patient out-of-pocket costs. We will compare how these outcomes differ for patients in HDHPs with and without medications subject to the deductible. We will assess effects in the overall population of patients with bipolar illness and in specific vulnerable subgroups, including racial/ethnic minorities, poorer patients, rural patients, and patients with other important comorbidities.

METHODS:

We will take advantage of an ongoing natural experiment whereby employers have shifted all their employees at once from traditional insurance to HDHPs. We will use the strongest quasi-experimental, longitudinal methods available to compare the experience of patients switched by their employers into HDHPs with contemporaneous patients whose employers remain in traditional plans. A major advantage of our approach is the inclusion of only employers whose employees had no choice of insurance plans, minimizing member-level selection bias.