Vitamin D Deficiency More Common Among Disabled And Black Older Women - Brief Article

Nutrition Research Newsletter, Jan, 2001

Vitamin D is essential for maintenance of bone density and calcium metabolism. A deficiency in this vitamin is associated with bone loss and fracture. Sunlight and diet are the two major sources of this vitamin. The risk of vitamin D deficiency increases with age, obesity, in renal disease and during the winter season. Public health measures in the United States have aimed efforts to decrease this deficiency by fortifying dairy products and cereals with vitamin D. However, there continues to be a high prevalence of vitamin D deficiency among older community-dwelling adults and homebound individuals. Preliminary evidence has also shown African American women to be at higher risk of vitamin D deficiency. Identification of groups at risk of deficiency is important as it is easily corrected through dietary supplementation.

The intent of a recent study was to determine the prevalence of vitamin D deficiency and to examine risk factors associated with this deficiency in older women. The subject cohort was taken from the Women's Health and Aging Study (WHAS) I and WHAS II, an observational study of women among the two-thirds least disabled, community-dwelling women. The women were all greater than 65 years of age, serum concentrations of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25[(OH).sub.2]D], intact parathyroid hormone (PTH), osteocalcin, and ionized calcium.

The subjects were classified into four domains of physical disability: 6.2% of subjects with 0 or 1 domain of disability and 12.6% of subjects with two or greater domains of disability were found to have vitamin D deficiency. Using univariate analysis, researchers found risk factors for vitamin D deficiency included increasing age, black race, low educational level, high body-mass index, high triceps skinfold thickness, increasing level of disability, winter season, and elevated creatinine concentration. After adjusting for other factors, being from the black race had a strong association with vitamin D deficiency.

It appears that vitamin D deficiency is a common problem in older, disabled, community-dwelling women. Efforts should be focused on preventing and correcting this deficiency, especially among older black women, as they appear to have a greater risk of developing vitamin D deficiency.

R. Semba, E. Garrett, B. Johnson, et al. Vitamin D deficiency among older women with and without disability. Am J Clin Nutr;72:1529-1534 (December, 2000) [Correspondence: R.D. Semba, 550 N Broadway, Ste. 700, Baltimore, MD 21205. E-mail: rdsemba@jhmi.edu].