Measure Serum Vitamin D Levels in All Your Black Male Patients

June 3, 2007
John Schieszer

Internal Medicine World Report, October 2006, Volume 0, Issue 0

From the American Society for Bone and Mineral Research Deficiency Linked to Cardiovascular/Metabolic Diseases

PHILADELPHIA?Black men have significantly lower levels of vitamin D, predisposing them to a host of illnesses suggest findings from a new study presented at the 28th Annual Meeting of the American Society for Bone and Mineral Research. The investigators recommend that primary care physicians assess vitamin D levels in all black men and consider supplementation if deficiencies are found.

Although racial and ethnic differences in bone mineral density (BMD) are well recognized, little is known about the relationship between 25-hydroxyvitamin D and BMD levels in men of different races/ ethnicities.

Michael Holick, MD,?PhD, professor of medicine, physiology, and biophysics at Boston University Medical Center, and colleagues studied the relationship between 25-hydroxyvitamin D and BMD in 1121 men (331 blacks, 365 Hispanics, and 425 whites) aged 30 to 79 years (mean age, 47 years) from the Boston Area Community Health/Bone Survey, a population-based random sample. The investigators recorded serum 25-hydroxyvitamin D levels and measured BMD in the femoral neck, trochanter, total hip, and lumbar spine.

After adjusting for factors such as age, weight, and height, mean levels of 25-hydroxyvitamin D were:

? 62 nmol/L in black men

? 82 nmol/L in Hispanic men

? 93 nmol/L in white men.

Overall, 40% of the blacks had low serum vitamin D levels compared with 20% of the Hispanic and 9% of the ?white men. ?

In contrast, age and height-adjusted BMD levels were 6% to 12% higher in black men than in white men at all sites measured. Hispanic men had 3% higher BMD at the femoral neck than white men.

The levels of vitamin D significantly correlated with BMD at all sites in white men but not with BMD at any site in the black or Hispanic men.

"We wanted to look at vitamin D status in African Americans, because the skin pigmentation decreases the ability of their skin to make vitamin D. We were concerned that they were at high risk of vitamin D deficiency, and we found that to be the case," Dr Holick told IMWR.

"We also were able to demonstrate that African-American men have higher bone density than white men, and these findings have important clinical implications. 25 Hydroxyvitamin D is a measure of vitamin D status, and it is now recognized that vitamin D status may be important in preventing many serious diseases that are more frequent in African Americans."

For example, he said, hypertension, diabetes, and cardiovascular disease are more common in blacks, and there is a growing body of scientific evidence that suggests an association between vitamin D status and the development of these conditions.

"There is no question that primary care physicians should be targeting black males for their vitamin D status, and that is not going on now," said Dr Holick. "Physicians don't see many black males having fractures, so they don't really relate their bone health to their calcium and vitamin D intake. But indeed vitamin D deficiency has insidious consequences for African-American health, especially for males."

Previous data have shown that vitamin D supplementation may lower the risk for pancreatic cancer by nearly 50% and that vitamin D deficiency is associated with an increased risk of colon, breast, and prostate cancers. Published studies in recent years have suggested that populations in areas of the world with greater sunlight exposure have a lower incidence of and mortality from prostate, breast, and colon cancers.