High Deductible Health Plans and Bipolar Disorder
Condition: Bipolar Disorder
MeSH terms: Bipolar Disorder
Study type: Observational

Summary: 
      Using eleven years (2004-2014) of claims data from the largest US commercial health insurer,
      the investigators will assess the impact of switching into high-deductible health plans
      (HDHPs) on outcomes for patients with bipolar disorder. Patient subgroups will include
      patients with and without high medication cost-sharing and vulnerable populations
      (racial/ethnic minorities, poor, rural, major comorbidities). Interviews with patients and
      caregivers recruited through a major advocacy group will provide further insights into the
      policy issues with real-life experiences.
    

Detailed description: 
      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.

      From preliminary data queries, we estimate a study population of ~160,000 members with
      bipolar disorder from 2004-2013. Our data include detailed information about insurance type,
      diagnoses, health services and pharmacy utilization, out-of-pocket payments, individual-level
      patient characteristics like income, and neighborhood-level factors like racial density. The
      unprecedented large sample size will allow us to answer questions about how patients from
      particular vulnerable subgroups respond to HDHPs, including patients who are Black or
      Hispanic, have low incomes, reside in rural areas, and have major comorbidities.

      PATIENT OUTCOMES:

      Our Aim 1 measures of the quality of bipolar treatment will include indicators of patients'
      access to appropriate care: prevalence and intensity of use of effective medications
      (antipsychotics, anticonvulsants); medication adherence; and, guideline-recommended clinical
      monitoring (regular outpatient mental health visits). Adverse events in Aim 2 will include
      psychiatric hospitalizations, which are potentially avoidable and often viewed as an
      indicator of suboptimal outpatient care. In Aim 3, we will assess changes under HDHPs in the
      co-payment amounts faced by patients for specific medical services, such as prescription
      fills and clinician visits, and the total burden of patient out-of-pocket costs.

      PATIENT AND STAKEHOLDER ENGAGEMENT:

      Our longstanding engagement with the National Alliance on Mental Illness (NAMI, the
      preeminent patient advocacy organization addressing issues around bipolar disorder) has
      shaped our study aims and our focus on measurable outcomes of particular concern to patients.
      We will solicit regular input from a local patient and family advisory panel (assembled with
      NAMI's assistance) on the refinement of methods, interpretation of study findings, shaping of
      recommendations, and dissemination of results. As study consultant, NAMI Medical Director Dr.
      Ken Duckworth will guide meetings of the patient panel and contribute perspectives from the
      broader community of patients and clinicians dealing with bipolar illness. Dr. Greg Simon,
      Director of the US Mental Health Research Network, will provide national expertise on patient
      experiences with serious mental illness in health plans.

      ANTICIPATED IMPACT:

      Our research will provide empirical data comparing how patients with bipolar illness fare
      under three insurance designs with vastly different requirements for cost-sharing. At a time
      when HDHP enrollment is exploding, the experience of patients with serious mental illnesses
      is largely unexamined. Advocacy groups will be able to use our findings to lobby for more
      patient-responsive benefit designs; policymakers will have evidence to redesign insurance
      benefits to better address the needs of vulnerable patients (e.g., by exempting mood
      stabilizing agents from deductibles).
    

Intervention name(s): Patient Interview
Intervention type(s): Other
Intervention description(s): Investigators will conduct in-depth interviews with approximately 40 commercially insured individuals with bipolar disorder or their family caregivers to explore how they navigate deductibles, copayments, and other complex insurance features. Investigators will also determine the health care services that patients most value and assess how they prioritize difficult health care cost tradeoffs.
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Investigators will include health plan members aged 12 to 63 years at the beginning of the
        baseline period. Consistent with prior research,89-91 we will use medical claims data and a
        validated algorithm to identify members who had at least two ambulatory encounters or one
        hospital encounter with a diagnosis of bipolar disorder. Intervention cohorts will include
        traditional plan members with bipolar illness who experience an employer-mandated switch to
        HSA-eligible HDHPs with full drug cost-sharing or to HSA-ineligible HDHPs that subject
        medications only to copayments as in traditional health plans.
      
Keywords: high-deductible health plans; medication adherence