Release Date: June 20, 2002
SAN FRANCISCO -- The first study of vitamin D status in a group of Kashmiri women and their babies has revealed across-the-board deficiency of the nutrient, which increases the risk of rickets, osteoporosis, other bone disorders and muscle weakness in this population.
Results of the investigation, conducted by endocrine researchers at the University of Buffalo and two institutions in Srinagar, India, were presented here today (June 20, 2002) at the 84th annual meeting of The Endocrine Society.
"This finding brings to light a serious public health problem," said Paresh Dandona, M.D., UB professor of medicine, director of the Diabetes-Endocrinology Center of Western New York, and senior author on the study.
"Kashmir has very long winters and many women remain completely covered even in summer, so we expected to see vitamin D deficiency, but we found much more than we expected."
Vitamin D is produced by the skin in the presence of sufficient sunlight. Ten to 15 minutes of sunshine three times weekly is considered adequate to produce the body's requirement of vitamin D. Deficiency is rare in the United States. Dandona published the first account of severe muscle weakness resulting from vitamin D deficiency in the U.S. in April 2000, after studying a small group of home-bound patients in Buffalo.
A native of India educated in the United Kingdom, Dandona said that muscle weakness due to vitamin D deficiency has been described for some time in the United Kingdom and Northern Europe, owing to the lack of sunshine in those regions. When research assistant Tufail Syed came from Kashmir to work in his lab, Dandona saw the opportunity to investigate the vitamin status in a population at risk for the deficiency due to climate and custom.
Colleagues at the LD Hospital in Srinagar, India, collected blood samples from 43 pregnant women during labor, cord blood from their 43 newborns and samples from 15 female medical students who were to serve as controls. Researchers expected the medical students to have normal vitamin D levels because they are better educated than the general female population. However, analysis of the blood samples showed moderate to severe vitamin D deficiency in all three groups, with the medical students having the lowest concentrations. Researchers could detect no vitamin D in samples from three of the students. Dandona speculated that the medical students may spend more time indoors than the pregnant women, many of whom came from rural areas.
For women, the minimum recommended blood level of vitamin D -- in the form of 25 hydroxy vitamin D, or 25(OH) D -- is 20 nanograms per milliliter (ng/ml). The mean level for the pregnant women in this study was 8.3 (ng/ml) and for the newborns, 5.8 ng/ml. Eleven of the babies were readmitted to the hospital with rickets within months, Dandona said. The mean level of vitamin D in blood samples from the student controls was 5.7 ng/ml.
Researchers also found several cases of higher-than-normal levels of parathyroid hormone in the adults, a condition caused by too little vitamin D. Too much parathyroid hormone results in further loss of bone.
Vitamin D deficiency can be remedied easily by drinking fortified milk or other fortified foods, exposure to sunlight or by taking vitamin pills. Dandona said he hopes to open a micronutrient clinic in Kashmir in the future to study and serve this population.
Also participating in this study were Shahida Mir M.D., of the LD Hospital in Srinagar; Ahmad Aljada, Ph.D.; Husam Ghanim, a doctoral student and Zaffar Amin, M.D., all of the UB Department of Medicine, and Mufti Suhail Sayeed, M.D., of Sher-i-Kashmir Institute of Medical Sciences (SKIIMS) in Srinagar. The Diabetes-Endocrinology Center of Western New York is located in Kaleida Health's Millard Fillmore Hospital in Buffalo.