Medicare transitional care management services' association with readmissions and mortality.

In 2013, the Centers for Medicare and Medicaid Services (CMS) introduced codes to reimburse outpatient providers for post-discharge transitional care management (TCM). Understanding the implications of TCM reimbursement on outcomes is crucial for evaluating CMS's investment and guiding future policy. We analyzed the association between physician organization (PO) TCM code use and post-discharge readmissions and mortality using 100% fee-for-service Medicare claims. Using a difference-in-differences approach we compared 1131 "high-TCM" POs (top quartile of TCM code use from 2015-2017) to 1133 "low-TCM" POs (bottom quartile) from before (2012) and after (2015-2017) TCM code implementation, controlling for PO and beneficiary attributes and readmission risk. TCM code use was associated with decreased 30- and 90-day readmissions (-0.31 [95%CI: -0.52, -0.09] and -0.42 [95% CI: -0.71, -0.14] percentage points, respectively), but no significant difference in mortality. Year-by-year, 2017 saw greatest readmission reduction, with a slight mortality reduction in that year only. Readmission reductions were greatest in POs not affiliated with health systems, Accountable Care Organizations (ACOs), or academic medical centers, and least in those with fewer primary care physicians. Narrow, indirect interventions like fee-for-service TCM billing code reimbursement may have limited potential to improve post-discharge outcomes overall. However, small independent practices may derive somewhat greater benefit from this support for post-discharge care.