IMPROVING THE EVIDENCE FOR UNSTABLE ANGINA GUIDELINES

该项目旨在改善 AHCPR 不稳定心绞痛实践指南的证据基础，该指南要求临床医生考虑对具有急性心肌缺血 (ACI) 症状的低风险患者进行门诊管理。利用急诊科决策的两项临床有效性试验、急性心脏缺血时间不敏感预测仪器 (ACI-TIPI) 影响试验和即将完成的 Sestamibi 扫描临床试验的资源，该项目将确定与分诊指南建议的一致性是否与短期不良结局发生率下降（非致命性心肌梗死和死亡）以及短期利用率下降（急诊科复诊、再入院、冠状动脉造影和血运重建）相关。通过图表审查，我们将根据 AHCPR 分类指南和其他不稳定心绞痛风险分层模型，根据短期不良结果的风险，提取对 9191 名研究患者进行分类所需的项目。对于每个指南风险组，我们将在分层逻辑回归模型中测试分诊处置对不良结果预测的独立贡献，控制患者级别、医生级别和医院级别的不良结果预测因素。由于这些预测因子的不平衡分布可能会导致“指南一致”与“指南不一致”分类处置组中不良结果的比较产生偏差，因此我们将研究两种病例组合调整方法：倾向评分和 ACI-TIPI 评分。由于除了指南之外，其他几种现有工具可能会改善急性心脏护理的决策，因此与其他可用的 ACI 预后模型相比，我们还将计算指南风险组在区分有或没有不良短期结果的患者方面的敏感性和特异性。拟议的研究将使政策制定者能够预测指南实施对结果、成本以及对有不稳定心绞痛症状的患者使用医疗保健服务的影响。

This project aims to improve the evidence base for the AHCPR Unstable Angina Practice Guideline, which challenges clinicians to consider outpatient management for low-risk patients with symptoms suggestive of acute cardiac ischemia (ACI). Capitalizing on the resources of two clinical effectiveness trials of ED decision making, the Acute Cardiac Ischemia Time Insensitive Predictive Instrument (ACI-TIPI) Impact Trial and the nearly completed Sestamibi Scan Clinical Trial, this project will determine whether agreement with guideline recommendations for triage is associated with decreased short-term rates of adverse outcomes (non-fatal myocardial infarction and death) and decreased short-term utilization (ED revisits, readmissions, coronary angiography, and revascularization). Through chart review, we will abstract items necessary to categorize 9191 study patients according to their risk of adverse short term outcomes, based on AHCPR triage guidelines and other unstable angina risk stratification models. For each guideline risk group, we will test the independent contribution of triage disposition to the prediction of adverse outcomes in hierarchical logistic regression models, controlling for the patient-level, physician-level, and hospital-level predictors of adverse outcomes. As unbalanced distribution of these predictors may bias comparisons of adverse outcome in "guideline- concordant" versus "guideline-discordant" triage disposition groups, we will examine two approaches for case-mix adjustment: propensity scores and ACI-TIPI scores. As several other existing instruments, in addition to guidelines, may improve decision-making in acute cardiac care, we will also compute the sensitivity and specificity of the guideline's risk groups in discriminating between patients with and without adverse short-term outcomes, compared to that of other available prognostic models for ACI. The proposed research will provide policymakers with the ability to project the impact of guideline implementation on outcomes, cost, and the use of health care services for patients with symptoms suggestive of unstable angina.