Increased circulating concentrations of bioactive PTH 1-84 in patients with heart failure.
ABSTRACT Background: Parathyroid hormone (PTH) is related to left ventricular hypertrophy and its circulating levels are associated with worse prognosis in patients with heart failure (HF). The objectives of our study were to measure the circulating levels of bioactive PTH 1-84 through third generation assay in HF patients, to determine their association with the disease severity as well as their relation with recognized biomarkers of HF worsening and prognosis. Methods: PTH 1-84 concentrations were determined in 76 HF patients and in 49 healthy volunteers. Circulating levels of amino-terminal pro-atrial natriuretic peptide (Nt-proANP), B-type natriuretic peptide (BNP), Nt-proBNP, proBNP and big endothelin-1 (Big ET-1) were also measured. Results: HF patients had increased PTH 1-84 levels in comparison to controls. A significant increase of the PTH 1-84 circulating concentrations was observed according to the New York Heart Association functional classes. PTH 1-84 circulating concentrations were also significantly correlated with Nt-proANP, BNP, Nt-proBNP, proBNP and Big ET-1. Conclusions: PTH 1-84 circulating levels are significantly increased in HF patients in comparison to healthy individuals. Our study has also demonstrated that circulating concentrations of bioactive PTH are related to HF severity and well-established biomarkers of the worsening of the disease.