Low levels of vitamin D linked with reduced survival rates in patients with heart failure.
The study, conducted at the University Medical Center, Groningen, in the Netherlands, also suggested that low levels of Vitamin D are associated with activation of the Renin Angiotensin System (RAS – a pivotal regulatory system in heart failure) and an altered cytokine profile.
“By showing that vitamin D is an independent predictor, we hoped to prove that it is a contributory factor to, rather than peripheral to, the development and prognosis of heart failure. With this new information, we then hope to provide better insight into the pathophysiology of heart failure,” said researcher Licette Liu.
The study is said to be the first conducted in a large cohort of patients recruited due to hospitalisation for heart failure, in which the role of vitamin D has been determined, along with the roles of plasma renin activity and cytokines.
Vitamin D concentration was assessed in plasma samples from 548 heart failure patients. According the researchers, patients with lower concentrations had a higher risk of death or required re-hospitalisation, whereas patients with higher concentrations had lower survival risks for these endpoints.
“Further, significant correlations between vitamin D, and Plasma Renin Activity and C-Reactive Protein were found. These correlations suggest that the association between vitamin D and the prognosis in heart failure may be explained by activation of the RAS and an altered cytokine profile.”
Although the observational study was limited as bystander and indirect effects of variables could not be discounted, researchers urged heat patients to ensure adequate vitamin D intake.
“This study provides compelling evidence that a high vitamin D status is associated with improved survival in heart failure patients. Until an intervention study has been designed and completed, it seems that we should advise patients with heart failure to maintain appropriate vitamin D levels by taking supplements, by eating oily fish or eggs, or simply by exposure to sunlight,” said Liu.
