Department of Orthopaedics, University of Rochester, New York.
Department of Public Health Sciences, University of Rochester, New York.
JAMA Health Forum. 2022 Feb 11;3(2):e215111. doi: 10.1001/jamahealthforum.2021.5111. eCollection 2022 Feb.
Medicare beneficiaries with Alzheimer disease and related dementias (ADRD) are a particularly vulnerable group in whom arthritis is a frequently occurring comorbidity. Medicare's mandatory bundled payment reform-the Comprehensive Care for Joint Replacement (CJR) model-was intended to improve quality and reduce spending in beneficiaries undergoing joint replacement surgical procedures for arthritis. In the absence of adjustment for clinical risk, hospitals may avoid performing elective joint replacements for beneficiaries with ADRD.
To evaluate the association of the CJR model with utilization of joint replacements for Medicare beneficiaries with ADRD.
This cohort study used national Medicare data from 2013 to 2017 and multivariable linear probability models and a triple differences estimation approach. Medicare beneficiaries with a diagnosis of arthritis were identified from 67 metropolitan statistical areas (MSAs) mandated to participate in CJR and 104 control MSAs. Data were analyzed from July 2020 to July 2021.
Implementation of the CJR model in 2016.
Outcomes were separate binary indicators for whether or not a beneficiary underwent hip or knee replacement. Key independent variables were the MSA group, before-CJR and after-CJR phase, ADRD diagnosis, and their interactions. The linear probability models controlled for beneficiary characteristics, MSA fixed effects, and time trends.
The study included 24 598 729 beneficiary-year observations for 9 624 461 unique beneficiaries, of which 250 168 beneficiaries underwent hip and 474 751 underwent knee replacements. The mean (SD) age of the 2013 cohort was 77.1 (7.9) years, 3 110 922 (66.4%) were women, 3 928 432 (83.8%) were non-Hispanic White, 792 707 (16.9%) were dually eligible for Medicaid, and 885 432 (18.9%) had an ADRD diagnosis. Before CJR implementation, joint replacement rates were lower among beneficiaries with ADRD (hip replacements: 0.38% vs 1.17% for beneficiaries with and without ADRD, respectively; < .001; knee replacements: 0.70% vs 2.25%; < .001). After controlling for relevant covariates, CJR was associated with a 0.07-percentage-point decline in hip replacements for beneficiaries with ADRD (95% CI, -0.13 to -0.001; = .046) and a 0.07-percentage-point decline for beneficiaries without ADRD (95% CI, -0.12 to -0.02; = .01) residing in CJR MSAs compared with beneficiaries in control MSAs. However, this change in hip replacement rates for beneficiaries with ADRD was not statistically significantly different from the change for beneficiaries without ADRD (percentage point difference: 0.01; 95% CI, -0.08 to 0.09; = .88). No statistically significant changes in knee replacement rates were noted for beneficiaries with ADRD compared with those without ADRD with CJR implementation (percentage point difference: -0.03, 95% CI, -0.09 to 0.02; = .27).
In this cohort study of Medicare beneficiaries with arthritis, the CJR model was not associated with a decline in joint replacement utilization among beneficiaries with ADRD compared with beneficiaries without ADRD in the first 2 years of the program, thereby alleviating patient selection concerns.
重要性：患有阿尔茨海默病和相关痴呆症（ADRD）的医疗保险受益人是一个特别脆弱的群体，他们经常患有关节炎等共病。医疗保险的强制性捆绑支付改革——全面关节置换护理（CJR）模式——旨在提高接受关节炎关节置换手术的受益人的质量并降低支出。在没有调整临床风险的情况下，医院可能会避免为患有 ADRD 的受益人进行择期关节置换。
目的：评估 CJR 模式与 Medicare 患有 ADRD 的受益人进行关节置换的使用之间的关联。
设计：这项队列研究使用了 2013 年至 2017 年的全国医疗保险数据，并使用多变量线性概率模型和三重差异估计方法。从参与 CJR 的 67 个大都市统计区（MSA）和 104 个对照组中确定了关节炎诊断的 Medicare 受益人。数据从 2020 年 7 月分析到 2021 年 7 月。
暴露因素：2016 年 CJR 的实施。
主要结果和测量：结果是受益人的单独二元指标，用于确定是否进行髋关节或膝关节置换。关键的独立变量是 MSA 组、CJR 前和 CJR 后阶段、ADRD 诊断及其相互作用。线性概率模型控制了受益人的特征、MSA 固定效应和时间趋势。
结果：该研究纳入了 24598729 个受益人生年观察和 9624461 名独特受益人的数据，其中 250168 名受益人的髋关节和 474751 名受益人的膝关节接受了置换。2013 年队列的平均（SD）年龄为 77.1（7.9）岁，3110922（66.4%）为女性，3928432（83.8%）为非西班牙裔白人，792707（16.9%）同时享受医疗补助和医疗保险，885432（18.9%）患有 ADRD 诊断。在 CJR 实施之前，患有 ADRD 的受益人的关节置换率较低（髋关节置换：分别为 0.38%和 1.17%， < .001；膝关节置换：0.70%和 2.25%， < .001）。在控制了相关协变量后，与 CJR 控制组相比，CJR 与 ADRD 受益人的髋关节置换减少了 0.07 个百分点（95%CI，-0.13 至 -0.001； = .046），与没有 ADRD 的受益人减少了 0.07 个百分点（95%CI，-0.12 至 -0.02； = .01）。然而，患有 ADRD 的受益人的髋关节置换率变化与没有 ADRD 的受益人的变化没有统计学上的显著差异（差异：0.01；95%CI，-0.08 至 0.09； = .88）。与没有 ADRD 的受益人相比，患有 ADRD 的受益人的膝关节置换率在 CJR 实施后没有统计学上的显著变化（差异：-0.03，95%CI，-0.09 至 0.02； = .27）。
结论：在这项对 Medicare 关节炎受益人的队列研究中，与没有 ADRD 的受益相比，CJR 模式在计划的前 2 年内并没有导致 ADRD 受益人的关节置换利用率下降，从而减轻了患者选择的担忧。
