Long-term Impact of Reduced Patient Out-of-pocket Costs on Diabetes Complications

项目总结/摘要 该项目旨在确定是否有3个自然实验，减少自付费用的糖尿病 患者长期改善急性和慢性糖尿病并发症。这些自然实验 包括：（1）雇主采用预防药物清单（PDL），使糖尿病相关药物为零，（2） 州立法限制患者自付胰岛素费用，以及（3）雇主从高成本转变为低成本。 可扣除的健康计划（HDHPs），大多数服务都有很大的财务障碍， 免赔额计划研究结果可以提供证据，说明在多个层面采取可行的干预措施， 糖尿病患者的健康。研究将利用一个大型的国家健康保险索赔数据库， 2007-2023年，研究小组在以前的项目中进行了改进。该项目的具体目标是： 1.评估（a）糖尿病并发症和（B）联邦、州和 感兴趣的自然实验。分析将评估2009-2023年急性可预防和 慢性微血管和大血管并发症，包括按关注的关键亚组进行分层。 与自然实验摄取相关的措施将包括年度PDL采用、州级胰岛素成本 趋势，以及HDHP到低免赔额计划的转换。这些分析将使用纵向的日历时间序列 结合点设计，根据不断变化的人口统计学、社会经济状况和合并症进行调整。 2.确定减少药物自付费用是否能改善糖尿病并发症。超过4次随访 年，目标2a将审查雇主是否从健康储蓄账户（HSA）-HDHPs转换， PDL HSA-HDHPs的自付药物费用与0美元预防药物降低了急性和慢性糖尿病 并发症目标2b将评估大约10个美国州限制胰岛素之前和之后的这些结果 费用分摊。分析将使用高度严格的中断时间序列和对照系列研究设计， 目标2a还将采用对照组设计的分段生存。 3.确定减少门诊和急诊部的自付费用是否能改善糖尿病 并发症分析将评估是否从门诊费用分摊较高的HDHP转换， 慷慨的低免赔额计划的急诊科护理降低了急性和慢性糖尿病的风险 随访4年以上的并发症。这一目标还将使用严格控制的中断时间序列， 分段生存设计 4.检查降低自付费用对关键糖尿病亚组的长期影响，包括 低收入和高发病率的成员。目标4将涉及目标2和3的分层分析， 收入、发病率、种族/民族和糖尿病严重程度等特征。这一目标将使用相同的 研究设计与目标2和3相同，但按感兴趣的因素分层。

PROJECT SUMMARY/ABSTRACT This project seeks to determine whether 3 natural experiments that reduce out-of-pocket costs for diabetes patients improve acute and chronic diabetes complications over the longer term. These natural experiments include: (1) employer adoption of preventive drug lists (PDLs) that make diabetes-related medications $0, (2) state legislation capping patient out-of-pocket costs for insulin, and (3) employer transitions from high- deductible health plans (HDHPs) with substantial financial barriers for most services to generous low- deductible plans. Results could provide evidence about actionable interventions at multiple levels that improve the health of diabetes patients. Studies will leverage a large, national health insurance claims database from 2007-2023 that the research team has refined under previous projects. The Specific Aims of the project are to: 1. Assess 15-year national trends in (a) diabetes complications and (b) uptake of federal, state, and employer natural experiments of interest. Analyses will assess 2009-2023 trends in acute preventable and chronic microvascular and macrovascular complications, including stratification by key subgroups of interest. Measures related to natural experiment uptake will comprise annual PDL adoption, state-level insulin cost trends, and HDHP to low-deductible plan switches. These analyses will use a longitudinal, calendar time series design with joinpoints, adjusted for changing demographics, socio-economic status, and co-morbidity. 2. Determine if reducing drug out-of-pocket costs improves diabetes complications. Over 4 follow-up years, Aim 2a will examine whether employer switches from health savings account (HSA)-HDHPs with high drug out-of-pocket costs to PDL HSA-HDHPs with $0 preventive drugs reduce acute and chronic diabetes complications. Aim 2b will assess these outcomes before and after approximately 10 US states limit insulin cost sharing. Analyses will use a highly rigorous interrupted time series with control series study design and Aim 2a will also apply a segmented survival with control group design. 3. Determine if reducing outpatient and emergency department out-of-pocket costs improves diabetes complications. Analyses will assess if switching from HDHPs with high cost sharing for outpatient and emergency department care to generous low-deductible plans reduces the risk of acute and chronic diabetes complications over 4 follow-up years. This aim will also use rigorous controlled interrupted time series and segmented survival designs. 4. Examine the long-term impact of reduced out-of-pocket costs on key diabetes subgroups including low-income and high-morbidity members. Aim 4 will involve stratifying Aims 2 and 3 analyses by characteristics such as income, morbidity, race/ethnicity, and diabetes severity. This aim will use the same study designs as for Aims 2 and 3 but stratified by the factors of interest.