Latest Renal Data Suggest Clinical Improvement and Skyrocketing Costs

MINNEAPOLIS, Aug. 10 -- Better prevention and treatment of end-stage renal disease have led to a clinical payoff but have failed to ease the financial burden, the latest data show.

The number of patients who started dialysis or had kidney transplants declined by 0.9% in 2004, the last year with complete data, Robert N. Foley, M.D., and Allan J. Collins, M.D., of the United States Renal Data System here, reported online in the Journal of the American Society of Nephrology.

That bit of good news was accompanied by grim cost estimates showing that end-stage-related expenditures rose by 57% from 1999 through 2004.

Renal replacement therapy, including dialysis and transplantation, consume a disproportionate amount of financial and human resources, the authors said, noting that costs associated with end-stage renal disease accounted for 6.7% of Medicare expenditures.

Medicare outlays for end-stage disease exceeded billion, and non-Medicare expenditures stood at .4 billion.

Any meaningful and lasting impact on disease outcomes and costs requires an effective interruption in the progression from chronic kidney disease to end-stage disease, the authors said. Moreover, they noted, the full impact of the growing epidemic of diabetes has yet to be determined.

In addition to the encouraging data on new-onset dialysis and transplantation, end-stage disease-related mortality continued a decline that began in the 1980s.

The one concern, the authors said, is the lack of improvement in survival in the first year after initiation of dialysis. First-year mortality in dialysis patients declined steadily from 1987 to 1993, but no further improvement has occurred since then.

Mortality for years 2 through 5 of dialysis has continued to decrease, however. The data are encouraging given that the age and comorbidity burden of dialysis patients continue to increase, Drs. Foley and Collins noted.

Diabetes remained the principal cause of end-stage renal disease in 2004, with a rate of 148.8 cases per million. In all likelihood, the association will strengthen absent a reversal in the burgeoning prevalence and incidence of diabetes, they said.

Incidence of end-stage disease has decreased in most demographic groups and by the principal causes of the condition, Foley and Collins said. One potential area of concern, they noted, is an apparent increase in the rate of diabetes-associated end-stage renal disease in younger African-Americans.

End-stage disease rates also appear to be rising in older individuals.

An aging population with a substantial burden of cardiovascular disease could make atherosclerotic renovascular disease a more prominent issue in end-stage disease, the authors suggested. A recent examination of U.S. Renal Data System figures on patients ages 67 and older showed that the prevalence of atherosclerotic renovascular disease increased from 7.1% in 1996 to 11.2% in 2001.

The current study also revealed improvement in several quality indicators in end-stage disease. Patients starting dialysis have less severe kidney disease compared with their predecessors. And use of fistulas to reduce the risk of complications with grafts or catheters has increased.

The data showed that 36.3% used fistulas as dialysis access, 25.5% used catheters, and 38.2% used grafts in 2003. The corresponding figures in 1998 were 27.8, 17.1, and 54.7%.

Overall, hospitalization figures have remained relatively static at approximately two admissions per year per dialysis patient, accounting for approximately 14 hospital days per year.

The authors expressed concern, however, about the growing practice of aggressively raising hemoglobin levels with recombinant erythropoietin. Recent studies have suggested higher hemoglobin targets may be harmful.

"[O]vershooting recommended hemoglobin targets may be dangerous, as may highly variable hemoglobin levels," Drs. Foley and Collins stated.

In summarizing their impressions of the data, the authors express a mix of enthusiasm and caution.

"[M]any of the trends observed in [our system's data] tend to generate cautious enthusiasm for the future, apart from the issue of costs, which continue to skyrocket," they stated.