Pre-ESRD Nephrology Care in Medicare versus VA Healthcare Systems

There are few available data on the benefits of maintenance dialysis for older adults with kidney failure or end-stage renal disease (ESRD) in the setting of another serious illness or multimorbidity. In that patient population, survival with dialysis may be limited, functional outcomes are often poor, and patients commonly discontinue dialysis. Guidelines are designed to encourage sharing decision-making that considers patient preferences, prognosis, and expected quality of life with dialysis. However, according to Manjula Kurella Tamura, MD, MPH, and colleagues, there is no consensus in the guidelines regarding which patients should forgo dialysis.

Among older Americans, there is variation in the likelihood of receiving dialysis treatment across geographic regions, suggesting the possibility that dialysis decisions are influenced by factors external to the patient. Compared with other industrialized countries, dialysis treatment appears to be more frequent in the United States; however, dialysis outcomes are generally worse in the United States.

Nearly 20% of patients initiating dialysis in the United States are veterans >65 years of age; annual costs of care exceed $100,000 per patient. Nearly all older veterans eligible for care in the Department of Veterans Affairs (VA) healthcare system are also eligible for Medicare, making it possible for those patients to receive pre-ESRD nephrology care in the VA or in Medicare. Those encounters influence the decisions regarding initiation of dialysis. The VA has no direct financial incentives to initiate dialysis in patients who might gain limited benefits from that therapy.

It is unknown whether there is an association between receipt of nephrology care prior to development of ESRD in Medicare versus the VA and more frequent use of dialysis and/or higher overall survival. Dr. Tamura et al. conducted a retrospective cohort study designed to compare initiation of dialysis and mortality among older veterans with incident kidney failure who received pre-ESRD nephrology care in Medicare versus the VA. Results were reported online in JAMA Internal Medicine [doi:10.1001/jamainternmed.2018.0411].

The researchers evaluated 11,215 veterans ≥67 years of age with incident kidney failure between January 1, 2008, and December 31, 2011. The main outcomes of interest were dialysis treatment and death within 2 years.

Of the 11,215 patients, 98.8% (n=11,085) were male, and mean age was 79.1 years. Patients who received pre-ESRD nephrology care in Medicare, compared with those who received pre-ESRD nephrology care in the VA, were older and more likely to be male, white, and married. On average, the Medicare-treated cohort lived farther from a VA medical center, were more likely to have a copayment for VA services, and to reside in rural areas and areas with a higher median income. They were also more likely to have missing estimated glomerular filtration rate (eGFR) values at follow-up. Following propensity-score matching, the cohort was well balanced on measured characteristics, indicated by standardized differences <10%.

Of the total cohort, 63.0% (n=7017) started dialysis within 2 years of incident kidney failure. Among those who received pre-ESRD nephrology care in Medicare, the unadjusted frequency of dialysis was 81.9% compared with 52.7% among patients who received pre-ESRD nephrology care in the VA (adjusted risk difference, 20 percentage points; 95% confidence interval [CI], 26-30 percentage points). Results were similar in propensity-matched analyses.

In analyses limited to patients with at least two pre-ESRD nephrology visits, there were large differences in the frequency of dialysis treatment between the Medicare cohort and the VA cohort (adjusted risk difference, 27 percentage points; 95% CI, 23-30 percentage points); in analyses limited to patients with a sustained eGFR of ≤15 mL/min/1.73 m2 (adjusted risk difference, 12 percentage points; 95% CI, 10-15 percentage points).

When the analysis required a 90-day duration for the low eGFR component of the incident kidney failure, the adjusted risk difference in dialysis initiation between the Medicare cohort and the VA cohort was 26 percentage points (95% CI, 24-28 percentage points). Of the patients who initiated dialysis, 5.0% (n=163) of those who had pre-ESRD nephrology care in Medicare started peritoneal dialysis versus hemodialysis, compared with 2.8% (n=108) of patients who received pre-ESRD nephrology care in VA (P<.01).

Differences in the frequency of dialysis treatment between patients in the Medicare cohort and those in the VA cohort were larger among those ≥80 years of age and among those with dementia or metastatic cancer, and less pronounced among patients with paralysis (all P<.05 for interaction). Neither race or Charlson Comorbidity Index score demonstrated effect modification.

Within 2 years of kidney failure, 47.1% (n=5280) of patients died. Of the patients who initiated dialysis, the mortality rate was 54.3% among those who received pre-ESRD care in Medicare versus 43.3% among those who received pre-ESRD care in the VA. Following adjustment, the differences were attenuated but remained significant (adjusted risk difference, 5 percentage points; 95% CI, 3-7 percentage points). In the propensity-matched cohort, results were similar (adjusted risk difference, 8 percentage points; 95% CI, 5-11 percentage points).

Study limitations cited by the authors included the lack of precision in estimates of the difference in initiation of dialysis treatment between Medicare and the VA due to uncertainty in the number of incident kidney failure cases without dialysis in Medicare; the inability to evaluate patient satisfaction with care; and, due to the observational design of the study, the results are susceptible to confounding.

In conclusion, the researchers said, “Dialysis appears to be the default treatment option for the majority of older veterans who receive pre-ESRD care in Medicare, but this pattern of care was not associated with better overall survival. Additional studies may help to determine the specific processes of care associated with these findings and whether they can be replicated among the rapidly growing number of integrated delivery systems outside of the VA.”

Takeaway Points

  1. The benefits of maintenance dialysis for older adults with end-stage renal disease (ESRD) are unclear, and it is not known whether the setting of pre-ESRD nephrology care has an effect on decisions regarding initiation of dialysis.
  2. Researchers conducted a retrospective cohort study of patients ≥67 years of age who received pre-ESRD nephrology care in Medicare versus the VA.
  3. Veterans who receive pre-ESRD nephrology care in Medicare initiate dialysis more often than those treated in the VA; yet are also more likely to die within 2 years.