Correlations Between Serum Intact Parathyroid Hormone (PTH) and N-terminal-probrain Natriuretic Peptide Levels in Elderly Patients with Chronic Heart Failure (CHF)

Objectives: The aim of this study was to investigate the association between PTH and Nt-proBNP in elderly patients with CHF in an attempt to gain insights into the role of PTH in a community-based cohort of elderly patients with CHF.Methods: A total of 182 consecutive CHF patients with follow-up for mortality after 3 years were prospectively studied. Serum levels of intact PTH, Nt-proBNP and biochemical parameters were examined. The enrolled patients were divided into groups by the levels of PTH and New York Heart Association (NYHA) functional classes.Results: A total of 66 (36%) patients had PTH values above the upper limit of the normal range. Serum creatinine (p = 0.001), estimated glomerular filtration rate (eGFR) (p = 0.001), Nt-proBNP (p < 0.001), serum calcium (p = 0.030), heart rate (p = 0.002) showed statistical significance in different stages of PTH. The mean PTH and Nt-proBNP levels increased as the NYHA functional class increased. The optimal cut-off value of PTH to predict CHF-related death was 48.98 pg/ml, with 57.14% sensitivity and 86.24% specificity. The best cut-off point of Nt-proBNP was 480 ng/ml with 76.47% sensitivity and 80.48% specificity. Over a mean follow-up of 3 years, Kaplan-Meier survival curves demonstrate that patients with higher levels of intact PTH had lower survival time, with a hazard ratio of 2.5 (95% CI 1.5-3.9).Conclusions: The study has shown that serum intact PTH level obtained in the elderly patients with CHF is a novel biomarker associated with Nt-proBNP and could provide supplementary information for the diagnosis and prognostic prediction of CHF, especially when it is used in combination with Nt-proBNP. (C) 2014 Elsevier Ireland Ltd. All rights reserved.