Less vitamin D linked to higher death rate

GRAZ, Austria, June 24 (UPI) -- People with lower blood levels of vitamin D appear to have an increased risk of death overall and from cardiovascular causes, Austrian researchers said.

Dr. Harald Dobnig of Medical University of Graz, in Austria, and colleagues studied 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels in 3,258 consecutive patients -- average age 62 -- who were scheduled for coronary angiography, testing at a single medical center between 1997 and 2000.

Blood levels of 25-hydroxyvitamin D, a measure of blood vitamin D levels, lower than 20 to 30 nanograms per milliliter have been associated with falls, fractures, cancer, immune dysfunction, cardiovascular disease and hypertension. These effects are thought to be mediated by the compound 1,25-dihydroxyvitamin D, which is produced by the body and also converted from 25-hydroxyvitamin D.

During about 7.7 years of follow-up, 22.6 percent of the participants died, including 62.8 percent who died of cardiovascular causes.

The study, published in the Archives of Internal Medicine, found death rates from any cause and from cardiovascular causes were higher among individuals in the lower one-half of 25-hydroxyvitamin D levels and the lowest one-fourth of 1,25-dihydroxyvitamin D levels.

These associations remained when the researchers accounted for other factors, including coronary artery disease, physical activity level and co-occurring diseases.