Directly Measured Free and Total 25-hydroxyvitamin D Levels in Relation to Metabolic Health in Multi-ethnic Postmenopausal Females in Saudi Arabia

Overview

Journal Endocr Connect

Specialty Endocrinology

Date 2021 Nov 16

PMID 34783311

Citations 1

Authors

Shatha Alharazy

M Denise Robertson

Susan Lanham-New

Muhammad Imran Naseer

Adeel G Chaudhary

Eman Alissa

Affiliations

Soon will be listed here.

Abstract

Background: Measurement of free 25-hydroyvitamin D (25(OH)D) status has been suggested as a more representative marker of vitamin D status than that of total 25(OH)D. Previously, free 25(OH)D could only be calculated indirectly; however, a newly developed direct assay for the measurement of free 25(OH)D is now available. The aim of this study therefore was to investigate directly measured total and free vitamin D levels association with metabolic health in postmenopausal healthy women living in Saudi Arabia.

Methods: A sample of 302 postmenopausal women aged ≥50 years (n = 302) living in Saudi Arabia were recruited in a cross-sectional study design. Blood samples were collected from subjects for measurement of serum levels of total 25(OH)D, directly measured free 25(OH)D, metabolic bone parameters, lipid profile, and other biochemical tests.

Results: A positive correlation was found between directly measured free and total 25(OH)D (r = 0.64, P< 0.0001). Total but not free 25(OH)D showed significant association with serum intact parathyroid hormone (P = 0.004), whilst free 25(OH)D but not total 25(OH)D showed a significant association with total cholesterol and LDL-C (P = 0.032 and P = 0.045, respectively).

Conclusions: Free 25(OH)D and total 25(OH)D were found to be consistently correlated but with different associations to metabolic health parameters. Further research is needed to determine which marker of vitamin D status would be the most appropriate in population studies.

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References

Lee M, Kearns M, Smith E, Hao L, Ziegler T, Alvarez J . Free 25-Hydroxyvitamin D Concentrations in Cystic Fibrosis. Am J Med Sci. 2015; 350(5):374-9. PMC: 4629503. DOI: 10.1097/MAJ.0000000000000592. View

Ross A, Manson J, Abrams S, Aloia J, Brannon P, Clinton S . 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. 2010; 96(1):53-8. PMC: 3046611. DOI: 10.1210/jc.2010-2704. View

Papandreou D, Hamid Z . The Role of Vitamin D in Diabetes and Cardiovascular Disease: An Updated Review of the Literature. Dis Markers. 2015; 2015:580474. PMC: 4630385. DOI: 10.1155/2015/580474. View

Deluca H . Overview of general physiologic features and functions of vitamin D. Am J Clin Nutr. 2004; 80(6 Suppl):1689S-96S. DOI: 10.1093/ajcn/80.6.1689S. View

Holick M . High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006; 81(3):353-73. DOI: 10.4065/81.3.353. View

Jemielita T, Leonard M, Baker J, Sayed S, Zemel B, Shults J . Association of 25-hydroxyvitamin D with areal and volumetric measures of bone mineral density and parathyroid hormone: impact of vitamin D-binding protein and its assays. Osteoporos Int. 2015; 27(2):617-26. PMC: 4924926. DOI: 10.1007/s00198-015-3296-6. View

Wang L, Song Y, Manson J, Pilz S, Marz W, Michaelsson K . Circulating 25-hydroxy-vitamin D and risk of cardiovascular disease: a meta-analysis of prospective studies. Circ Cardiovasc Qual Outcomes. 2012; 5(6):819-29. PMC: 3510675. DOI: 10.1161/CIRCOUTCOMES.112.967604. View

Ferri E, Casati M, Cesari M, Vitale G, Arosio B . Vitamin D in physiological and pathological aging: Lesson from centenarians. Rev Endocr Metab Disord. 2019; 20(3):273-282. DOI: 10.1007/s11154-019-09522-y. View

Olerod G, Mattsson Hulten L, Hammarsten O, Klingberg E . The variation in free 25-hydroxy vitamin D and vitamin D-binding protein with season and vitamin D status. Endocr Connect. 2017; 6(2):111-120. PMC: 5428908. DOI: 10.1530/EC-16-0078. View

10.

Jorde R, Grimnes G . Vitamin D and metabolic health with special reference to the effect of vitamin D on serum lipids. Prog Lipid Res. 2011; 50(4):303-12. DOI: 10.1016/j.plipres.2011.05.001. View

11.

Johnsen M, Grimnes G, Figenschau Y, Torjesen P, Almas B, Jorde R . Serum free and bio-available 25-hydroxyvitamin D correlate better with bone density than serum total 25-hydroxyvitamin D. Scand J Clin Lab Invest. 2014; 74(3):177-83. DOI: 10.3109/00365513.2013.869701. View

12.

Prentice A, Schoenmakers I, Jones K, Jarjou L, Goldberg G . Vitamin D Deficiency and Its Health Consequences in Africa. Clin Rev Bone Miner Metab. 2014; 7:94-106. PMC: 4126271. DOI: 10.1007/s12018-009-9038-6. View

13.

Norman A . From vitamin D to hormone D: fundamentals of the vitamin D endocrine system essential for good health. Am J Clin Nutr. 2008; 88(2):491S-499S. DOI: 10.1093/ajcn/88.2.491S. View

14.

Barrea L, Frias-Toral E, Pugliese G, Garcia-Velasquez E, Carignano M, Savastano S . Vitamin D in obesity and obesity-related diseases: an overview. Minerva Endocrinol (Torino). 2020; 46(2):177-192. DOI: 10.23736/S2724-6507.20.03299-X. View

15.

Holick M, Binkley N, Bischoff-Ferrari H, Gordon C, Hanley D, Heaney R . Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011; 96(7):1911-30. DOI: 10.1210/jc.2011-0385. View

16.

Safadi F, Thornton P, Magiera H, Hollis B, Gentile M, Haddad J . Osteopathy and resistance to vitamin D toxicity in mice null for vitamin D binding protein. J Clin Invest. 1999; 103(2):239-51. PMC: 407885. DOI: 10.1172/JCI5244. View

17.

Hollis B . Assessment of vitamin D nutritional and hormonal status: what to measure and how to do it. Calcif Tissue Int. 1996; 58(1):4-5. DOI: 10.1007/BF02509538. View

18.

Laird E, Rhodes J, Kenny R . Vitamin D and Inflammation: Potential Implications for Severity of Covid-19. Ir Med J. 2020; 113(5):81. View

19.

Bikle D, Gee E, Halloran B, Kowalski M, Ryzen E, Haddad J . Assessment of the free fraction of 25-hydroxyvitamin D in serum and its regulation by albumin and the vitamin D-binding protein. J Clin Endocrinol Metab. 1986; 63(4):954-9. DOI: 10.1210/jcem-63-4-954. View

20.

Matsuoka L, Ide L, Wortsman J, MacLAUGHLIN J, Holick M . Sunscreens suppress cutaneous vitamin D3 synthesis. J Clin Endocrinol Metab. 1987; 64(6):1165-8. DOI: 10.1210/jcem-64-6-1165. View