Medicare Enrollment and Spending Among Patients Initiating Dialysis After the Affordable Care Act.

Importance: Medicare finances health care for most US patients with end-stage kidney disease (ESKD), regardless of age. Medicare enrollment may have slowed for patients with incident ESKD who gained access to new private insurance options with the 2014 passage of the Affordable Care Act (ACA) and introduction of the ACA Marketplace.

Objective: To describe trends in public and private insurance coverage and dialysis spending among patients with incident ESKD from 2012 to 2017.

Design, setting, and participants: This serial cross-sectional study included patients 18 to 64 years old in Colorado who were not enrolled in Medicare at dialysis initiation. Data analysis was conducted from May to August 2023.

Exposure: Introduction of the ACA Marketplace in 2014.

Main outcomes and measures: Medicare, Medicaid, or private insurance enrollment in the first year after dialysis initiation, and dialysis spending by insurance type.

Results: Of 2005 patients included in the sample, 1416 (70.6%) were 45 to 64 years old, and 1259 (62.8%) were male. A lower proportion of patients with incident ESKD starting dialysis were newly enrolled in Medicare in the years following the ACA (361 of 713 [50.6%]) compared to 2 years prior (420 of 595 [70.6%]). Unadjusted rates of switching from Medicaid to Medicare 1 year after dialysis initiation decreased 14.3 percentage points over time (68.9% in 2012-2013 vs 58.3% and 54.6% in 2014-2015 and 2016-2017, respectively). Unadjusted rates of switching from private insurance to Medicare 1 year after dialysis initiation decreased by 22.3 percentage points (68.1% in 2012-2013 vs 52.2% and 45.8% in 2014-2015 and 2016-2017, respectively). Over the entire 2012 to 2017 period, quarterly dialysis spending in the first year of dialysis among patients with private insurance was higher than among those with Medicare coverage ($26 351-$29 781 vs $10 039-$12 741).

Conclusions and relevance: This cross-sectional study demonstrates that lower Medicare enrollment rates over time among those initiating dialysis may be inducing higher social spending. This finding raises concerns about the effectiveness of Medicare policies and federal leverage to improve access, outcomes, and value of dialysis care.