Evaluating risk of ESRD in the urban poor

Abstract

The capacity of risk prediction to guide management of CKD in underserved health settings is unknown. We conducted a retrospective cohort study of 28,779 adults with nondialysis-requiring CKD who received health care in two large safety net health systems during 1996-2009 and were followed for ESRD through September of 2011. We developed and evaluated the performance of ESRD risk prediction models using recently proposed criteria designed to inform population health approaches to disease management: proportion of cases followed and proportion that needs to be followed. Overall, 1730 persons progressed to ESRD during follow-up (median follow-up=6.6 years). ESRD risk for time frames up to 5 years was highly concentrated among relatively few individuals. A predictive model using five common variables (age, sex, race, eGFR, and dipstick proteinuria) performed similarly to more complex models incorporating extensive sociodemographic and clinical data. Using this model, 80% of individuals who eventually developed ESRD were among the 5% of cohort members at the highest estimated risk for ESRD at 1 year. Similarly, a program that followed 8% and 13% of individuals at the highest ESRD risk would have included 80% of those who eventually progressed to ESRD at 3 and 5 years, respectively. In this underserved health setting, a simple five-variable model accurately predicts most cases of ESRD that develop within 5 years. Applying risk prediction using a population health approach may improve CKD surveillance and management of vulnerable groups by directing resources to a small subpopulation at highest risk for progressing to ESRD.

Keywords: CKD; ESRD; ethnic; minority; progression of chronic renal failure.

Copyright © 2015 by the American Society of Nephrology.

Figures

Figure 1.

The estimated proportion of ESRD events captured (PCF) among a given proportion of subjects at highest estimated risk of ESRD (PNF) for models 1–4 at 1-, 3-, and 5-year time frames. Model 2 outperformed model 1, especially at 3- and 5-year time frames, with models 3 and 4 providing modest improvement over model 2. The performances of all models were highest for the 1-year time frame and declined over time. On the basis of model 2, an estimated 91% (97%) of events occurring within 1 year were captured in 10% (20%) of subjects at highest estimated risk of ESRD; those values decreased to 83% (91%) and 74% (86%) for 3- and 5-year time frames, respectively.