Cardiac Event Biomarker Linked to Volume Overload
NTproBNP may be linked not to cardiac dysfunction but to volume overload in hemodialysis patients
FRIDAY, May 28 (HealthDay News) -- Among stable hemodialysis patients, N-terminal probrain type natriuretic peptide (NTproBNP) may not be associated with cardiac dysfunction but appears to be dependent on factors associated with volume overload, and may also be elevated in those with malnutrition, according to a study published online May 27 in the Clinical Journal of the American Society of Nephrology.
John Booth, M.D., of the Royal Free Hospital in London, and colleagues determined volume status before and after dialysis in 72 stable hemodialysis outpatients using multifrequency bioimpedance, and examined the relationship to NTproBNP.
The researchers found that NTproBNP was linked to markers of volume overload and cardiac dysfunction on simple correlation. However, as assessed by transthoracic echo or nuclear medicine scintigraphy, NTproBNP was not associated with cardiac dysfunction but was dependent on factors linked to volume overload. Multivariate logical regression analysis showed that the strongest association was with the pre-dialysis ratio of extracellular water/total body water. Also associated with NTproBNP were post-dialysis mean arterial blood pressure, dialysate calcium concentration, and change in extracellular fluid volume with dialysis.
"In this study, NTproBNP was not associated with cardiac dysfunction as assessed by transthoracic echo or nuclear medicine scintigraphy but was dependent on factors associated with volume overload. However, because bioimpedance results can also be affected by malnutrition with loss of cell mass, NTproBNP may be elevated not only in patients with volume overload, but also those with malnutrition," the authors write.