Low levels of vitamin D are associated with a markedly higher risk of heart attack and early death, according to a new research.
The study involved more than 10,000 Danes and was conducted by the University of Copenhagen and Copenhagen University Hospital.
Vitamin D deficiency has traditionally been linked with poor bone health. However, the results from several population studies indicate that a low level of this important vitamin may also be linked to a higher risk of ischemic heart disease, a designation that covers heart attack, coronary arteriosclerosis and angina. Other studies show that vitamin D deficiency may increase blood pressure, and it is well known that high blood pressure increases the risk of heart attack.
"We have now examined the association between a low level of vitamin D and ischemic heart disease and death in the largest study to date. We observed that low levels of vitamin D compared to optimal levels are linked to 40 percent higher risk of ischemic heart disease, 64 percent higher risk of heart attack, 57 percent higher risk of early death, and to no less than 81 percent higher risk of death from heart disease," said Dr. Peter Brondum-Jacobsen, Clinical Biochemical Department, Copenhagen University Hospital.
The higher risks are visible, even after adjustment for several factors that can influence the level of vitamin D and the risk of disease and death. This is one of the methods scientists use to avoid bias.
The population study that forms the basis for this scientific investigation is the Copenhagen City Heart Study, where levels of vitamin D were measured in blood samples from 1981-1983. Participants were then followed in the nationwide Danish registries up to the present.
"With this type of population study, we are unable to say anything definitive about a possible causal relationship. But we can ascertain that there is a strong statistical correlation between a low level of vitamin D and high risk of heart disease and early death,” said Borge Nordestgaard, clinical professor at the Faculty of Health and Medical Sciences, University of Copenhagen and senior physician at Copenhagen University Hospital..
The explanation may be that a low level of vitamin D directly leads to heart disease and death. However, it is also possible that vitamin deficiency is a marker for poor health generally," he added.
The scientists are now working to determine whether the connection between a low level of vitamin D and the risk of heart disease is a genuine causal relationship.
The study has been published in the well-reputed American journal Arteriosclerosis, Thrombosis and Vascular Biology.