Over time, high-sensitivity TnT replaces NT-proBNP as the most powerful predictor of death in patients with dialysis-dependent chronic renal failure

Abstract

Background Cardiac biomarkers are emerging as a potentially powerful prognostic tool for renal-dialysis patients. The optimal biomarker and/or combination of biomarkers for predicting mortality remain uncertain. This study evaluates the prognostic value of the new high-sensitivity troponin T (TnT) assay compared to established biomarkers. Methods All patients had blood sampled for prospective assessment of the prognostic value of traditional risk markers including albumin and CRP, and cardiac biomarkers BNP, NT-proBNP, TnT and TnI. Patients were closely monitored clinically. Mortality and morbidity outcomes were documented for a national morbidity and mortality database. Stored samples were subsequently used to measure TnT with a new high-sensitivity assay. Results After a median of 30 months from blood collection, NT-proBNP was the most powerful predictor of all-cause mortality, along with albumin. After a median of 46.7 months the new high-sensitive TnT assay was the only cardiac biomarker predictive of all-cause mortality. TnT was detectable in all dialysis patients using the high-sensitive TnT assay with a cut-point of 24.15 ng/L below which all patients survived. Conclusions The new hs-TnT is the most powerful biomarker for prognostic classification for all-cause mortality of all the commonly used biomarkers for our renal-dialysis population. Our study also suggests that cardiac biomarkers have a different prognostic ability for different time frames with NT-proBNP being a better predictor for early mortality and troponin for later mortality.