Factors Associated with Warfarin Use in Dialysis Patients w/ Atrial Fibrillation

描述(申请人提供)：中风是终末期肾病(ESRD)透析患者死亡和残疾的主要原因。慢性心房颤动(AF)在透析人群中很常见，是一种潜在的可改变的卒中危险因素。华法林是一种经过充分研究的干预措施，用于降低患有房颤的普通人群的中风风险，被国家肾脏基金会认为是治疗透析患者房颤的合适疗法。然而，即使在合适的透析患者中，华法林的使用率似乎也很低，这可能是因为肾病学家对华法林在非透析人群中的随机对照试验结果是否适用于一般虚弱的透析患者深表怀疑。 许多有关卒中和华法林在患有房颤的透析患者中的使用的关键问题需要紧急检查。由于床边从业者、指导方针形成的思想领袖和医疗政策制定者在信息真空中运作，因此了解华法林在中风风险环境中的使用是当务之急。在美国透析患者中使用华法林预防中风的模式从未在大样本中报道过，主要是因为将纵向药物处方与个体患者层面的基于医疗索赔的诊断联系起来所需的工具以前从未广泛获得。 这项建议旨在确定人口统计因素、合并症和医疗保健系统因素(如都市化程度和透析单位的利润状况)如何与透析人群中的华法林处方相关。此外，还将研究基础医疗保健系统因素是否与该人群中中风发生率的差异有关。这些问题将通过使用观察数据进行调查，这将为有效地对患有房颤的透析患者使用华法林的决定因素进行大规模研究提供机会。为了实现这些目标，将使用美国肾脏数据系统(USRDS)医疗保险数据和医疗补助药物索赔数据之间的新链接。最终，这里提出的K23项目旨在将申请者发展成为一名成功的独立卫生服务研究员，他可以在ESRD中研究中风和心血管疾病预防问题，最终为减轻这一不断增长的人口的疾病负担做出贡献。 公共卫生相关性：减少透析患者因心血管原因死亡是美国国立卫生研究院使命的核心。考虑到ESRD人群的规模以及这些患者中心血管疾病的患病率，调查与使用华法林降低中风风险相关的因素是至关重要的。目前对这一主题知之甚少；本申请将是确定与使用这一重要疗法相关的因素的关键的第一步。 中风在透析患者中非常常见。中风的一个主要原因是心房颤动，可以开出血液稀释药华法林来降低中风风险，但由于不确定的原因，透析患者很少开这种药。为了帮助确定华法林不经常使用的原因，拟议的项目将使用联邦医疗保险和州医疗补助数据库创建一个新的链接数据库，以确定在庞大且不断增长的透析人口中决定华法林使用的人口统计、共病和医疗保健系统因素(如透析单位的利润状况和城市化程度)。

DESCRIPTION (provided by applicant): Stroke is a major cause of death and disability in end stage renal disease (ESRD) population on dialysis. Chronic atrial fibrillation (AF), common in the dialysis population, is a potentially-modifiable stroke risk factor. Warfarin, a well-studied intervention used to reduce stroke risk in the general population with AF, is considered appropriate therapy for dialysis patients with AF by the National Kidney Foundation. However, use rates of warfarin appear to be low even in suitable dialysis patients, which probably originates from a deep sense of skepticism among nephrologists that the results of randomized controlled trials of warfarin in the non-dialysis population are applicable to generally frail dialysis patients. Many critical issues regarding both stroke and warfarin use in dialysis patients with AF require urgent examination. An understanding of how warfarin is used in the setting of stroke risk is imperative, since bedside practitioners, guideline-forming thought leaders, and healthcare policymakers are operating in an information vacuum. Patterns of warfarin use for stroke prevention in AF have never been reported in a large sample of U.S. dialysis patients, primarily because the tools required to link longitudinal medication prescriptions to medical claims-based diagnoses at the level of the individual patient have never before been widely available. This proposal seeks to determine how demographic factors, comorbidities, and healthcare system factors (such as degree of urbanicity and the profit status of dialysis units) are associated with warfarin prescription in the dialysis population. Additionally, whether foundational healthcare system factors are associated with variation in stroke rates in this population will be examined. These questions will be investigated through the use of observational data, which offers the opportunity to efficiently undertake a large study of determinants of warfarin use in dialysis patients with AF. To accomplish these aims, a novel linkage between the United States Renal Data System (USRDS) Medicare data and Medicaid medication claims data will be used. Ultimately, the K23 project proposed here is designed to develop the applicant into a successful independent health services researcher who can investigate issues of stroke and cardiovascular disease prevention in ESRD, ultimately contributing to the reduction of disease burden in this growing population. PUBLIC HEALTH RELEVANCE: Reducing death from cardiovascular causes in dialysis patients is central to the mission of the NIH. Given both the size of the ESRD population as well as the prevalence of cardiovascular disease in these patients, investigation into the factors associated with warfarin use to reduce stroke risk is of the utmost importance. Little is presently known about this topic; the present application will be a critical first step in determining the factors associated with use of this important therapy. Stroke is very common in dialysis patients. A major cause of stroke is atrial fibrillation, for which the blood-thinning medicine warfarin can be prescribed to lower stroke risk but which is prescribed infrequently in dialysis patients for uncertain reasons. To help determine why warfarin is used infrequently, the proposed project will create a novel linked database using Medicare and state Medicaid databases to ascertain the demographic, comorbidity, and healthcare system factors (such as profit status and degree of urbanicity of dialysis units) determining warfarin use in the large and growing dialysis population.