Aims: To investigate levels of vitamin D and parathyroid hormone (PTH) in a population of heart failure (HF) patients, and to evaluate whether vitamin D and PTH are related to prognosis.
Methods and results: This was a prospective study of 148 HF outpatients (mean age 68 years, 102 men) with follow-up for mortality after 3½ years. Levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), PTH, 25-hydroxyvitamin D (25-OHD), and several other biomarkers were examined. Mortality and cardiovascular mortality were analysed in multivariable regression analyses adjusting for other independent prognostic variables. Vitamin D deficiency (≤50 nmol/L) was prevalent in 43% of the population; 26% had elevated PTH levels; none had primary hyperparathyroidism. We found a strong and independent significant association of both PTH and vitamin D to mortality, which was independent of other clinically important parameters [NT-proBNP, estimated glomerular filtration rate (eGFR), age, and left ventricular ejection fraction (LVEF)]. Both PTH and vitamin D were also significantly associated with all cause mortality. In an adjusted model, we found a hazard ratio of 1.9 (confidence interval 1.1-3.4) for vitamin D deficiency and 2.0 (1.0-3.8) for the upper median of PTH, respectively.
Conclusion: In this relatively small prospective study, PTH and vitamin D were independently associated with all cause and cardiovascular mortality in patients with HF. This was independent of other known risk factors such as eGFR, LVEF, NT-proBNP, and age.