Association of Medicare bundled payment model with joint replacement care for people with dementia

Background: We examined whether the Comprehensive Care for Joint Replacement (CJR) model was associated with changes in the receipt of joint replacement among people with Alzheimer's disease and related dementias (ADRD) as well as spending, health service use, and postsurgical outcomes among people with ADRD who underwent a joint replacement surgery.

Methods: Retrospective cohort study using 2013-2017 Medicare claims and Minimum Data Set. We used a difference-in-differences analysis to compare people with ADRD residing in CJR-participating treatment areas versus nonparticipating control areas on the receipt of joint replacement, episode spending during the index hospitalization and subsequent 90-day post-discharge period, discharges to an institutional post-acute care setting, and readmissions within 90 days of hospital discharge.

Results: Our sample included 3,361,950 Medicare enrollees with ADRD (2,156,995 women [64%]; mean [SD] age, 83 [8.0] years; 2,646,405 white [78%], 344,478 black [10%], 224,010 Hispanic [7%]). The receipt of replacement among people with ADRD changed similarly between CJR-participating treatment and control areas after CJR model was implemented, suggesting no association of CJR model with the receipt of replacement. Among people with ADRD who received joint replacement, the CJR model was associated with a $1029 decrease in spending per episode (95% confidence interval [CI] -$1577, -$481, p < 0.001), a 1.62 percentage point decrease in discharges to an institutional post-acute care setting (95% CI -3.17, -0.07, p = 0.04), but no changes in 90-day readmission (95% CI -2.68, 0.00, p = 0.051).

Conclusions: Despite concerns that the CJR model could hinder people with ADRD from receiving joint replacement, the receipt of joint replacement did not change among people with ADRD under CJR. The CJR model was associated with decreased spending for people with ADRD who received joint replacements, driven by reduced discharges to an institutional post-acute care setting, without any changes in 90-day readmission.