Filtration Markers May Predict ESRD and Mortality Risks

Concentrations of four markers of filtration, individually and in combination, are consistently associated with the risk of progression to end stage renal disease (ESRD), reports a study in the American Journal of Kidney Diseases.

Members of the Chronic Kidney Disease Biomarkers Consortium analyzed filtration markers and their association with 1-year change in measured (mGFR) and estimated (eGFR) glomerular filtration rate. The study included observational data on 317 patients from the Modification of Diet in Renal Disease study and 373 patients from the African American Study of Kidney Disease and Hypertension (AASK).

At 12- and 24-month follow-up visits, patients underwent measurement of creatinine, cystatin C, β-trace protein (BTP), and β2-microglobulin (B2M), along with mGFR. Associations with ESRD and all-cause mortality per 30% decline in mGFR or eGFR were analyzed for individual markers and for the average of four markers.

In both groups of patients, 1-year declines in mGFR, eGFR based on creatinine, and eGFR based on BTP were significantly associated with incident ESRD. The average of all four markers was also associated with ESRD. The only filtration marker more strongly associated with ESRD risk in both studies was decline in eGFRBTP.

Decline in eGFRCr was associated with all-cause mortality only in AASK: incidence rate ratio 4.17 per 30% decline. This was not significantly different from the association with mGFR. None of the other filtration markers was associated with mortality. Increase in mGFR and eGFR was not significantly associated with ESRD or mortality risk.

Repeated assessment of filtration markers might help to predict clinical outcomes in chronic kidney disease. The new study provides initial data on clinical outcomes associated with change in concentration of some novel filtration markers.

The results suggest that declines in mGFR, eGFRCr, eGFRBTP are significantly associated with incident ESRD. The average of creatinine, cystatin C, BTP, and B2M is also “consistently associated” with progression to ESRD. The investigators conclude, “Measurement of BTP over time may offer additional information about future ESRD risk,” [Rebholz CM, et al. Risk of ESRD and mortality associated with change in infiltration markers. Am J Kidney Dis 2017; doi: 10.1053/j.ajkd.2017.04.025].

August 2017 (Vol. 9, Number 8)