VA's Lower Intensity Treatment of Kidney Failure – Compared to Medicare – Does Not Result in Associated Increased Mortality

BACKGROUND:
The benefits of maintenance dialysis for older adults who develop kidney failure or end-stage renal disease (ESRD) in the context of another serious illness or multi-morbidity are uncertain. Veterans older than 65 years account for nearly 20% of patients starting maintenance dialysis in the U.S., and nearly all older Veterans eligible for VA care are also eligible for Medicare. Therefore, older Veterans can receive pre-ESRD nephrology care in VA or Medicare, and these encounters shape decisions about whether to begin dialysis. This retrospective cohort study compared the initiation of dialysis and mortality among Veterans (n=11,215, ages 67 and older) with incident kidney failure who received pre-ESRD care in fee-for-service Medicare vs. VA between January 2008 and December 2011. Primary outcomes that were measured included treatment with maintenance dialysis and mortality within two years of incident kidney failure. Investigators also examined demographics, VA co-pay, comorbidities, and driving distance to the closest VAMC with nephrology sub-specialty care. Further, because patients who use Medicare for sub-specialty care differ from those who use VA in several important characteristics that could confound the association between care setting and outcome, investigators also conducted a propensity score-matched analysis. Data were analyzed between March 2016 and September 2017.

FINDINGS:

• Older Veterans who received pre-ESRD nephrology care in Medicare received dialysis more often than Veterans who received VA care (82% vs. 53%), yet Medicare patients were more likely to die within two years compared with VA patients (54% vs 43%).
• Differences in the frequency of dialysis treatment between Medicare and VA were larger among Veterans aged 80 years or older and among Veterans with dementia or metastatic cancer – subgroups that are less likely to realize a survival benefit from dialysis.

IMPLICATIONS:

• Study results suggest that the VA healthcare system favors lower intensity treatment of kidney failure without an associated increase in mortality.

LIMITATIONS:

• Estimates of the difference in initiation of dialysis treatment between Medicare and VA lacked precision due to uncertainty in the number of kidney failure cases without dialysis in Medicare.
• Investigators were unable to determine patient preferences for dialysis – or the extent to which preferences influenced the setting in pre-ESRD care.

AUTHOR/FUNDING INFORMATION:
This study was partly funded by HSR&D. Drs. Gale and Asch are with HSR&D's Center for Innovation to Implementation (Ci2i) in Palo Alto, CA.

Tamura M, Thomas I, Montez-Rath M, Kapphahn K, Desai M, Gale R, and Asch S. Association between Dialysis Initiation and Mortality among Older Veterans with Kidney Failure Treated in Medicare vs the Department of Veterans Affairs. JAMA Internal Medicine. April 9, 2018;e-pub ahead of print.