Mandatory Medicare Bundled Payment Program for Lower Extremity Joint Replacement and Discharge to Institutional Postacute Care: Interim Analysis of the First Year of a 5-Year Randomized Trial.

Importance: Bundled payments are an increasingly common alternative payment model for Medicare, yet there is limited evidence regarding their effectiveness.
Objective: To report interim outcomes from the first year of implementation of a bundled payment model for lower extremity joint replacement (LEJR).
Design, Setting, and Participants: As part of a 5-year, mandatory-participation randomized trial by the Centers for Medicare & Medicaid Services, eligible metropolitan statistical areas (MSAs) were randomized to the Comprehensive Care for Joint Replacement (CJR) bundled payment model for LEJR episodes or to a control group. In the first performance year, hospitals received bonus payments if Medicare spending for LEJR episodes was below the target price and hospitals met quality standards. This interim analysis reports first-year data on LEJR episodes starting April 1, 2016, with data collection through December 31, 2016.
Exposure: Randomization of MSAs into the CJR bundled payment model group (75 assigned; 67 included) or to the control group without the CJR model (121 assigned; 121 included). Instrumental variable analysis was used to evaluate the relationship between inclusion of MSAs in the CJR model and outcomes.
Main Outcomes and Measures: The primary outcome was share of LEJR admissions discharged to institutional postacute care. Secondary outcomes included the number of days in institutional postacute care, discharges to other locations, Medicare spending during the episode (overall and for institutional postacute care), net Medicare spending during the episode, LEJR patient volume and patient case mix, and quality-of-care measures.
Results: Among the 196 MSAs and 1633 hospitals, 131 285 eligible LEJR procedures were performed during the study period (mean volume, 110 LEJR episodes per hospital) among 130 343 patients (mean age, 72.5 [SD, 0.91] years; 65% women; 90% white). The mean percentage of LEJR admissions discharged to institutional postacute care was 33.7% (SD, 11.2%) in the control group and was 2.9 percentage points lower (95% CI, −4.95 to −0.90 percentage points) in the CJR group. Mean Medicare spending for institutional postacute care per LEJR episode was $3871 (SD, $1394) in the control group and was $307 lower (95% CI, −$587 to −$27) in the CJR group. Mean overall Medicare spending per LEJR episode was $22 872 (SD, $3619) in the control group and was $453 lower (95% CI, −$909 to $3) in the CJR group, a statistically nonsignificant difference. None of the other secondary outcomes differed significantly between groups.
Conclusions and Relevance: In this interim analysis of the first year of the CJR bundled payment model for LEJR among Medicare beneficiaries, MSAs covered by CJR, compared with those that were not, had a significantly lower percentage of discharges to institutional postacute care but no significant difference in total Medicare spending per LEJR episode. Further evaluation is needed as the program is more fully implemented.
Trial Registration: ClinicalTrials.gov Identifier: NCT03407885; American Economic Association Registry Identifier: AEARCTR-0002521

研究背景：捆绑式付费是美国联邦医疗保险（Medicare）领域日益普及的替代性付费模式，但目前针对其有效性的相关实证证据仍较为有限。
研究目的：报告下肢关节置换术（lower extremity joint replacement, LEJR）相关病例全照护周期捆绑式付费模式实施首年的中期研究结果。
研究设计、研究场景与研究对象：作为美国医疗保险和医疗补助服务中心（Centers for Medicare & Medicaid Services）一项为期5年的强制参与随机试验的组成部分，符合纳入标准的都市统计区（Metropolitan Statistical Areas, MSA）被随机分配至下肢关节置换术全流程综合护理（Comprehensive Care for Joint Replacement, CJR）捆绑式付费组，或对照组。在首个绩效年度内，若某医院收治的下肢关节置换术病例的联邦医疗保险支出低于目标价格，且该医院达到质量标准，则可获得奖励性付费。本次中期分析纳入的研究数据为2016年4月1日启动、数据收集截至2016年12月31日的下肢关节置换术病例。
干预措施：将都市统计区随机分配至CJR捆绑式付费组（75个被分配，最终67个纳入分析）或无CJR模式的对照组（121个被分配，全部121个纳入分析）。本研究采用工具变量分析（instrumental variable analysis）法，评估都市统计区被纳入CJR模式与研究结局之间的关联。
主要结局与测量指标：主要结局为下肢关节置换术患者收治后转入机构性急性后期照护的占比。次要结局包括：机构性急性后期照护的住院天数、转入其他照护地点的比例、病例全照护周期内的联邦医疗保险总支出（含机构性急性后期照护支出）、病例全照护周期内联邦医疗保险净支出、下肢关节置换术患者诊疗量与患者病例组合，以及医疗质量相关指标。
研究结果：本研究共纳入196个都市统计区与1633家医院，研究期间共完成131285例符合纳入标准的下肢关节置换术，涉及130343名患者（患者平均年龄72.5岁，标准差0.91；65%为女性；90%为白人），单医院平均下肢关节置换术病例量为110例。对照组中，下肢关节置换术患者转入机构性急性后期照护的平均占比为33.7%（标准差11.2%），CJR组该占比平均降低2.9个百分点（95%置信区间：-4.95至-0.90个百分点）。对照组中，每例下肢关节置换术患者的机构性急性后期照护相关联邦医疗保险平均支出为3871美元（标准差1394美元），CJR组该支出平均减少307美元（95%置信区间：-587至-27美元）。对照组中，每例下肢关节置换术患者的联邦医疗保险总平均支出为22872美元（标准差3619美元），CJR组该支出平均减少453美元（95%置信区间：-909至3美元），该差异无统计学显著性。其余次要结局在两组间均无显著差异。
研究结论与意义：本次针对联邦医疗保险参保人群的下肢关节置换术CJR捆绑式付费模式首年中期分析结果显示，与未纳入CJR模式的都市统计区相比，纳入CJR模式的都市统计区中，下肢关节置换术患者转入机构性急性后期照护的占比显著更低，但两组患者每例下肢关节置换术相关的联邦医疗保险总支出无显著差异。随着该项目的全面推进，仍需开展进一步评估。
试验注册：ClinicalTrials.gov 标识符：NCT03407885；美国经济学会注册库标识符：AEARCTR-0002521