The Elderly with Vitamin D Deficiency Die Earlier*

Saturday Oct 24, 2009 (foodconsumer.org) -- Two recent studies suggest that vitamin D deficiency can be a cause for increased risk of early deaths in the elderly.

One study led by S. Pilz and colleagues from Medical University of Graz in Graz, Austria found that low serum levels of 25-hydroxyvitamin D [25(OH)D] are associated with an increased risk of all-cause and cardiovascular mortality. The study was published in the Nov 2009 issue of Clinical Endocrinology.

The other study led by AA Ginde and colleagues University of Colorado Denver, Aurora, Colorado found similar associations and the results were reported in the Jun 22, 2009 issue of Journal of the American Geriatrics Society.

Pilz et al. measured fasting serum 25(OH)D in 614 study subjects during 2000 to 2001 and then followed the participants for 6.2 years during which 51 deaths with 21 from cardiovascular events were recorded.

They found that compared to those whose vitamin D were in the higher three quartiles, people with serum levels of vitamin in the lowest quartile were 97 percent more likely to die from all causes and 378 percent more likely to die from cardiovascular disease.

The researchers concluded that low vitamin D levels are associated with all-cause mortality; cardiovascular mortality with even more pronounced.

But, they say that it remains unknown whether vitamin D deficiency is the cause or a consequence of a poor health status. Trial studies are needed to clarify this.

Ginde et al. have also come to the similar findings.

The researchers analyzed data from 3408 people aged 65 or older who were participating in the Third National Health and Nutrition Examination Survey (NHANES III) between 1988 and 1994. The participants were followed for mortality through 2000.

Serum 25(OH)D was measured at baseline or the beginning of the study. The median level of vitamin D was 66 nmol/L. During the median 7.3 years of follow-up, 1,493 or 44 percent of the participants died with 767 deaths from cardiovascular disease.

After all risk factors such as demographics, season, and cardiovascular risk factors were considered, the researchers found an inverse association between all cause mortality and baseline 25(OH)D.

Compared to subjects with 25(OH)D levels at 100 nmol/L or higher, the death risk for those whose vitamin D levels were at less than 25.0 nmol/L were 83 percent higher and the risk for those with vitamin D levels between 25.0 and 49.9 nmol/L was 47 percent higher.

Similarly, compared to those with more than 100 nmol/L of vitamin D in their blood, those who had less than 25 nmol/L were 136 percent more likely to die from cardiovascular disease, such as heart attacks and stroke, and 42 percent more likely to die from non-cardiovascular disease.

For more information on vitamin D and disease, visit the website of Vitamin D Council.

By David Liu and editing by Rachel Stockton