Objectives: Vitamin D deficiency is highly prevalent and has been linked to increased morbidity and mortality. There has been an increase in testing for vitamin D with a concomitant increase in costs. While individual factors are significantly linked to vitamin D status, prior studies have not yielded a model predictive of vitamin D status or 25(OH)D levels. The purpose of this investigation was to determine if a prediction model of vitamin D could be developed using extensive demographic data and laboratory parameters.
Methods: Patient data from 6 Veterans Administration Medical Centers were extracted from medical charts.
Results: For the 14,920 available patients, several factors including triglyceride level, race, total cholesterol, body mass index, calcium level, and number of missed appointments were significantly linked to vitamin D status. However, these variables accounted for less than 15% of the variance in vitamin D levels. While the variables correctly classified vitamin D deficiency status for 71% of patients, only 33% of those who were actually deficient were correctly identified as deficient.
Conclusion: Given the failure to find a sufficiently predictive model for vitamin D deficiency, we propose that there is no substitute for laboratory testing of 25(OH)D levels. A baseline vitamin D 3 daily replacement of 1000-2000 IU initially with further modification based on biannual testing appears to factor in the wide variation in dose response observed with vitamin D replacement and is especially important in high-risk groups such as ethnic minorities.
1. Holick MF, Chen TC. Vitamin D deficiency: a worldwide problem with health consequences. Am J Clin Nutr 2008;87:1080S-1086S.
2. Gallacher SJ, McQuillian C, Harkness M, et al. Prevalence of vitamin D inadequacy in Scottish adults with non-vertebral fragility fractures. Curr Med Res Opin 2005;21:1355-1361.
3. Atkins GJ, Anderson PH, Findlay DM, et al. Metabolism of vitamin D3 in human osteoblasts: evidence for autocrine and paracrine activities of 1 alpha,25-dihydroxyvitamin D3. Bone 2007;40:1517-1528.
4. Mark BL, Carson JA. Vitamin D and autoimmune disease-implications for practice from the multiple sclerosis literature. J Am Diet Assoc 2006;106:418-424.
5. Lappe JM, Travers-Gustafson D, Davies KM, et al. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr 2007;85:1586-1591.
6. Ross AC, Manson JE, Abrams SA, et al. The 2011 report on dietary reference intakes for calcium and vitamin D from the Institute of Medicine: what clinicians need to know. J Clin Endocrinol Metab 2011;96:53-58.
7. Holick MF. The D-batable Institute of Medicine report: a D-lightful perspective. Endocr Pract 2011;17:143-149.
8. Heaney RP, Holick MF. Why the IOM recommendations for vitamin D are deficient. J Bone Miner Res2011;26:455-457.
9. Grant WB, Peiris AN. Possible role of serum 25-hydroxyvitamin D in black-white health disparities in the United States. J Am Med Dir Assoc 2010;11:617-628.
10. Holick MF, Siris ES, Binkley N, et al. Prevalence of vitamin D inadequacy among postmenopausal North American women receiving osteoporosis therapy. J Clin Endocrinol Metab 2005;90:3215-3224.
11. Aloia JF, Patel M, Dimaano R, et al. Vitamin D intake to attain a desired serum 25-hydroxyvitamin D concentration. Am J Clin Nutr 2008;87:1952-1958.
12. Horne BD, May HT, Muhlestein JB, et al. Exceptional mortality prediction by risk scores from common laboratory tests. Am J Med 2009;122:550-558.
13. Tsiaras WG, Weinstock MA. Factors influencing vitamin d status. Acta Derm Venereol 2011;91:115-124.
14. Singh SK, Manjure S, Stott P, et al. Does routine blood bone biochemistry predict vitamin D insufficiency in elderly patients with low-velocity fractures? J Orthop Surg (Hong Kong) 2004;12:31-34.
15. Talwar SA, Swedler J, Yeh J, et al. Vitamin-D nutrition and bone mass in adolescent black girls. J Natl Med Assoc 2007;99:650-657.
16. Arunabh S, Pollack S, Yeh J, et al. Body fat content and 25-hydroxyvitamin D levels in healthy women. J Clin Endocrinol Metab 2003;88:157-161.
17. Alemayehu AA, Abebe Y, Gibson RS. A 24-h recall does not provide a valid estimate of absolute nutrient intakes for rural women in southern Ethiopia [published online ahead of print February 2, 2011]. Nutrition 2011.
18. Hall KL, Denda CE, Yeung H. Dietary vitamin d intake among elderly residents in a veterans' centre.Can J Diet Pract Res 2010;71:49-52.
19. Erbas B, Ebeling PR, Couch D, et al. Suburban clustering of vitamin D deficiency in Melbourne, Australia. Asia Pac J Clin Nutr 2008;17:63-67.
20. Grant WB, Boucher BJ. Requirements for vitamin D across the life span [published online ahead of print January 17, 2011]. Biol Res Nurs 2011.
21. Grant WB. The Institute of Medicine did not find the vitamin D-cancer link because it ignored UV-B dose studies. Public Health Nutr 2011;14:745-746.
22. Hathcock JN, Shao A, Vieth R, et al. Risk assessment for vitamin D. Am J Clin Nutr 2007;85:6-18.
23. Grant WB, Garland CF, Gorham ED. An estimate of cancer mortality rate reductions in Europe and the US with 1,000 IU of oral vitamin D per day. Recent Results Cancer Res 2007;174:225-234.
24. Talwar SA, Aloia JF, Pollack S, et al. Dose response to vitamin D supplementation among postmenopausal African American women. Am J Clin Nutr 2007;86:1657-1662.
25. Fu L, Yun F, Oczak M, et al. Common genetic variants of the vitamin D binding protein (DBP) predict differences in response of serum 25-hydroxyvitamin D [25(OH)D] to vitamin D supplementation. Clin Biochem 2009;42:1174-1177.
26. Peiris AN, Bailey B, Manning T, et al. Testing for vitamin D deficiency in veterans-is there a seasonal bias? J Am Med Dir Assoc 2010;11:128-131.