CA125 outperforms NT-proBNP in the prediction of maximum aerobic capacity in heart failure with preserved ejection fraction and kidney dysfunction.

Abstract

Heart failure with preserved ejection fraction (HFpEF) often coexists with chronic kidney disease (CKD). Exercise intolerance is a major determinant of quality of life and morbidity in both scenarios. We aimed to evaluate the associations between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and carbohydrate antigen 125 (CA125) with maximal aerobic capacity (peak VO2) in ambulatory HFpEF and whether these associations were influenced by kidney function. This single-centre study prospectively enrolled 133 patients with HFpEF who performed maximal cardiopulmonary exercise testing. Patients were stratified across estimated glomerular filtration rate (eGFR) categories (<60ml/min/1.73m2 versus ≥60ml/min/1.73m2). The mean age of the sample was 73.2±10.5years and 56.4% were female. The median of peak VO2 was 11.0ml/kg/min (interquartile range 9.0-13.0). A total of 67 (50.4%) patients had an eGFR <60ml/min/1.73m2. Those patients had higher levels of NT-proBNP and lower peak VO2, without differences in CA125. In the whole sample, NT-proBNP and CA125 were inversely correlated with peak VO2 (r=-0.43, P<.001 and r=-0.22, P=.010, respectively). After multivariate analysis, we found a differential association between NT-proBNP and peak VO2 across eGFR strata (P for interaction=.045). In patients with an eGFR ≥60ml/min/1.73m2, higher NT-proBNP identified patients with poorer maximal functional capacity. In individuals with eGFR <60ml/min/1.73m2, NT-proBNP was not significantly associated with peak VO2 [β=0.02 (95% confidence interval -0.19-0.23), P=.834]. Higher CA125 was linear and significantly associated with worse functional capacity without evidence of heterogeneity across eGFR strata (P for interaction=.620). In patients with stable HFpEF, NT-proBNP was not associated with maximal functional capacity when CKD was present. CA125 emerged as a useful biomarker for estimating effort intolerance in HFpEF irrespective of the presence of CKD.