Vitamin Information Center

Chronic kidney disease patients may see their risk of death drop by one quarter if they take a form of vitamin D, a new study says.

In a study of more than 1,400 people with chronic kidney disease, those that were taking the drug calcitriol, a form of activated vitamin D, had a 26 per cent reduction in their risk of death versus those who were not on the drug. Overall, the patients on calcitriol had their risk of either death or dialysis due to a loss of kidney function fall by 20 per cent.

The study is published in the Journal of the American Society of Nephrology.

A healthy human body uses first the liver and then the kidneys to convert vitamin D obtained through diet and sunlight into an active form that the body can use. However, it is believed that patients with chronic kidney disease are unable to do complete the second step.

They are often prescribed activated vitamin D to help lower elevated levels of the parathyroid hormone, which can lead to a weakening of the bones. However, people with kidney disease often suffer from calcified, or stiff, blood vessels, which can lead to a host of cardiovascular problems. Vitamin D increases calcium levels in the blood, which doctors fear could exacerbate this problem.

“We did find that people who got the activated vitamin D drug did have a higher risk of having a high calcium level in the blood,” study author Dr. Bryan Kestenbaum of the University of Washington told Ctv.ca.

“But the overall amount of people that that happened to was relatively small, and the overall balance was that people who got the activated vitamin D drug survived longer.”

Kestenbaum speculated that vitamin D leads to decreased mortality rates because of its known ability to lower risk factors for cardiovascular disease, including high blood pressure, diabetes and inflammation.

He said that the next step in this field of research would be to conduct randomized clinical trials to confirm vitamin D’s effect on survival rates among patients with kidney disease.

Low levels of vitamin D may put older people at a higher risk of depression, a study has found.

Researchers also estimated that 13 per cent of all people aged over 65 could be depressed.

The study, carried out by scientists in Amsterdam and published in Science Daily, found that a deficiency in vitamin D causes high blood levels of the parathyroid hormone, which has been linked to depression.

Of the 1,282 older people aged between 65 and 95 studied, 169 had a minor depressive illness and 26 were majorly depressed. Those with depression were found to have 14 per cent lesser vitamin D in their blood levels.

Over half of the women and 38.8 per cent of the men studied had insufficient vitamin D levels.

The authors of the study write: “Decreased vitamin intake may be secondary to depression, but depression may also be the consequence of poor vitamin D status.”

Decreased outdoor activity and different housing or clothing habits were all believed to decrease vitamin D.

However, a healthy dose of sun exposure can relieve minor feelings of depression.