Medicare advantage and dialysis facility choice

Abstract

Objective: To compare the characteristics of dialysis facilities used by traditional Medicare (TM) and Medicare advantage (MA) enrollees with end-stage kidney disease (ESKD).

Data sources: We used 20% TM claims and 100% MA encounter data from 2018 and publicly available data from the Centers for Medicare and Medicaid Services.

Study design: We compared the characteristics of the dialysis facilities treating TM and MA patients in the same ZIP code, adjusting for patient characteristics. The outcome variables were facility ownership, distance to the facility, and several measures of facility quality.

Data collection/extraction: We identified point prevalent dialysis patients as of July 15, 2018.

Principal findings: Compared to TM patients in the same ZIP code, MA patients were 1.84 percentage points more likely to be treated at facilities owned by the largest two dialysis organizations and 1.85 percentage points less likely to be treated at an independently owned facility. MA patients went to further and lower quality facilities than TM patients in the same ZIP code. However, these differences in facility quality were modest. For example, while the mean dialysis facility mortality rate was 21.85, the difference in mortality rates at facilities treating MA and TM patients in the same ZIP code was 0.67 deaths per 100 patient-years. Similarly, MA patients went to facilities that were, on average, 0.15 miles further than TM patients in the same ZIP code.

Conclusion: MA enrollees with ESKD were more likely than TM enrollees in the same ZIP code to use the dialysis facilities owned by the two largest chains, travel further for care, and receive care at lower quality facilities. While the magnitude of differences in facility distance and quality was modest, the direction of these results underscores the importance of monitoring dialysis network adequacy as ESKD MA enrollment continues to grow.

Keywords: Medicare; chronic disease; health care financing/insurance/premiums; health policy/politics/law/regulation; managed care organizations (e.g., HMOs/PPOs/IPAs); ownership/governance (for-profit/NFP/public/chains/systems).

FIGURE 1

Differences in ownership of facilities treating Medicare advantage versus traditional Medicare dialysis patients. Includes point prevalent Medicare dialysis patients on July 15, 2018, as determined in 20% fee‐for‐service claims and 100% Medicare advantage encounter data. Values are ordinary least squares regression coefficients and 95% confidence intervals of the association between Medicare advantage enrollment (versus Traditional Medicare enrollment) and the given ownership variable, which was coded as 0/1 and used in separate regressions. Values are multiplied by 100 to represent percentage point differences in probability. A vertical line is shown at zero, which would indicate in no difference in use of the given ownership type across traditional Medicare and Medicare advantage. All regressions include ZIP code fixed effects and adjust for dual eligibility status, race/ethnicity, sex, original reason for Medicare entitlement, age, and age squared. Observations were weighted by the inverse probability of being in the data. Facilities are classified as owned by other dialysis organizations if they are owned by American Renal Associates, Dialysis Clinics, Inc., or US Renal Care, Inc. [Color figure can be viewed at wileyonlinelibrary.com]