Association of maximal stress ergometry performance with troponin T and abdominal aortic calcification score in advanced chronic kidney disease

Background: Cardiac biomarkers Troponin T (TnT) and N-terminal pro-B-type natriuretic peptide (proBNP) and abdominal aortic calcification score (AAC) are associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). The effects of cardiac biomarkers and AAC on maximal exercise capacity in CKD are unknown and were studied. Methods: One hundred seventy-four CKD 4-5 patients not on maintenance dialysis underwent maximal bicycle ergometry stress testing, lateral lumbar radiograph to study AAC, echocardiography and biochemical assessments. Results: The subjects with proportional maximal ergometry workload (WMAX%) less than 50% of the expected values had higher TnT, proBNP, AAC, left ventricular end-diastolic diameter, left ventricular mass index, E/e' and pulse pressure, and lower global longitudinal strain compared to the better performing patients. TnT (beta = - 0.09, p = 0.02), AAC (beta = - 1.67, p < 0.0001) and diabetes (beta = - 11.7, p < 0.0001) remained significantly associated with WMAX% in the multivariable model. Maximal ergometry workload (in Watts) was similarly associated with TnT and AAC in addition to age, male gender, hemoglobin and diastolic blood pressure in a respective multivariate model. AAC and TnT showed fair predictive power for WMAX% less than 50% of the expected value with AUCs of 0.70 and 0.75, respectively. Conclusions: TnT and AAC are independently associated with maximal ergometry stress test workload in patients with advanced CKD.