Recovery of renal function among ESRD patients in the US medicare program

Abstract

Background: Patients started on long term hemodialysis have typically had low rates of reported renal recovery with recent estimates ranging from 0.9-2.4% while higher rates of recovery have been reported in cohorts with higher percentages of patients with acute renal failure requiring dialysis.

Study design: Our analysis followed approximately 194,000 patients who were initiated on hemodialysis during a 2-year period (2008 & 2009) with CMS-2728 forms submitted to CMS by dialysis facilities, cross-referenced with patient record updates through the end of 2010, and tracked through December 2010 in the CMS SIMS registry.

Results: We report a sustained renal recovery (i.e no return to ESRD during the available follow up period) rate among Medicare ESRD patients of > 5% - much higher than previously reported. Recovery occurred primarily in the first 2 months post incident dialysis, and was more likely in cases with renal failure secondary to etiologies associated with acute kidney injury. Patients experiencing sustained recovery were markedly less likely than true long-term ESRD patients to have permanent vascular accesses in place at incident hemodialysis, while non-White patients, and patients with any prior nephrology care appeared to have significantly lower rates of renal recovery. We also found widespread geographic variation in the rates of renal recovery across the United States.

Conclusions: Renal recovery rates in the US Medicare ESRD program are higher than previously reported and appear to have significant geographic variation. Patients with diagnoses associated with acute kidney injury who are initiated on long-term hemodialysis have significantly higher rates of renal recovery than the general ESRD population and lower rates of permanent access placement.

Figure 1. Histogram showing time to renal recovery for the entire cohort and for those patients with ATN – for those patients who do have sustained recovery of renal function.

Figure 2. Maps demonstrating the significant geographical variation in the overall rates of renal recovery and the rates of renal recovery for patients initiated on hemodialysis with a diagnosis of “tubular necrosis”.

Figure 3. Kaplan Meier curves showing comparison of the rates of sustained recovery of renal function by diagnosis among Medicare ESRD patients.