Drug Cost Containment Changes and Quality of Care for Mentally Ill Dual Enrollees

说明(由申请人提供)：同时接受医疗补助和医疗保险保险的残疾、低收入美国人(即双重参保人)是医疗保险人口中增长最快的部分之一。这些受益人中约有三分之一(估计。250万)患有昂贵的、往往使人虚弱的精神疾病，包括精神分裂症和双相情感障碍。这些双重参与者中药物治疗依从性差会导致更差的健康和昂贵的下游临床事件，包括因严重精神疾病(SMI)住院。2003年联邦医疗保险现代化法案(MMA)于2006年1月1日将双重参保人的门诊处方药覆盖责任从个人州医疗补助计划转移到由联邦医疗保险计划资助的私人D部分计划。医疗保险和医疗补助服务中心(CMS)随机将双重受益人分配给保费相对较低的D部分处方药计划(PDP)。这些独立的PDP可以在计划处方表中包括的处方药的数量和类型上有所不同，并可以采用使用管理方法，例如对任何药物处方进行事先授权(PA)。由于每个州都确定了自己的医疗补助覆盖政策，双重受益人在过渡到D部分覆盖之前面临着一系列药物覆盖福利。例如，在15个州，双重登记的人对处方数量有上限。因此，2006年过渡到D部分扩大了他们的药物覆盖范围，并消除了代价高昂的不良健康事件的一个潜在风险因素。然而，大多数州将抗精神病药物和抗惊厥治疗排除在医疗补助优先授权(PA)之外，而PDP经常使用PA作为管理药品成本的主要方法。因此，随着药品保险责任从州政府转移到私人计划，双重登记的受益人在获得门诊处方药方面面临的国家决定的费用障碍较少，但在获得精神药物方面可能面临更多由计划决定的行政障碍。我们将分别分析D部分在四个不同地域的大型州的影响：两个州对处方数量设置上限，并在2004至2007年间拥有相对较高的共同支付金额(南卡罗来纳州：每月限制4张处方；加利福尼亚州：每月限制6张)，以及两个在同一时期没有上限但共同支付金额相对较低的州(密苏里州、新泽西州)。在目标1中，我们将使用一个强大的准实验设计，即多重中断时间序列，来检查这种转变对人群水平的影响：(1)精神科药物使用的流行率和持久性；(2)非药物精神科服务的使用；以及(3)费用。在目标2中，我们在患者水平上使用随机设计来评估覆盖范围限制对精神科药物使用(包括停用和更换药物)、精神科门诊和急诊室就诊以及费用的影响。在目标3中，我们将使用这两种设计来检验政策变化对精神分裂症和双相情感障碍患者高危亚群(由躯体共病和少数群体状态定义)的影响。

DESCRIPTION (provided by the applicant): Disabled, low income Americans who receive both Medicaid and Medicare insurance coverage (i.e., dual enrollees), represent one of the fastest growing segments of the Medicare population. About one-third of these beneficiaries (est. 2.5 million) have expensive, often debilitating mental illness, including schizophrenia and bipolar disorder. Poor drug treatment adherence among these dual enrollees leads to worse health and expensive downstream clinical events including hospitalizations for severe mental illness (SMI). The Medicare Modernization Act of 2003 (MMA) transferred the responsibility for outpatient prescription drug coverage for dual enrollees from individual state Medicaid programs to private Part D plans funded by the Medicare program on January 1, 2006. The Centers for Medicare and Medicaid Services (CMS) randomly assigns dual beneficiaries to Part D Prescription Drug Plans (PDPs) with relatively low premiums. These standalone PDPs can vary in the numbers and types of prescription drugs included in the plan formulary and can employ utilization management approaches such as prior authorization (PA) for any drug prescriptions. Because each state determined its own Medicaid coverage policies, dual beneficiaries faced a range of drug coverage benefits prior to their transition to Part D coverage. For example, in 15 states, dual enrollees had caps on the number of prescriptions. Thus, the transition to Part D in 2006 expanded their drug coverage and removed a potential risk factor for costly adverse health events. Most states, however, excluded antipsychotic and anticonvulsant therapy from Medicaid prior authorization (PA), while PDPs often use PA as the primary approach for managing drug costs. Thus, as drug coverage responsibility shifts from states to private plans, dually enrolled beneficiaries face fewer state-determined cost barriers to outpatient prescription drug access, but potentially more plan-determined administrative barriers to psychotropic drug access. We will analyze the impact of Part D separately in four large and geographically diverse states: two that placed caps on the number of prescriptions and had relatively higher copayments between 2004 and 2007 (South Carolina: limit of 4 prescriptions per month; California: limit of 6 per month), and two that had no caps and relatively lower copayments during the same period (Missouri, New Jersey). In Aim 1, we will use a strong quasi-experimental design, Multiple Interrupted Time Series, to examine the population level impacts of this transition on: (1) the prevalence and persistence of psychiatric medication use; (2) use of non-drug psychiatric services; and (3) costs. In Aim 2 we use a randomized design at the patient level to estimate the effect of coverage restrictions on use of psychiatric medications (including discontinuation and switching of medications), psychiatric outpatient and ER visits, and costs. In Aim 3 we will use both designs to examine the impact of the policy changes among at-risk subgroups (defined by somatic comorbidities and minority status) of patients with schizophrenia and bipolar disorder.