Investigation of the Change in Vitamin D Levels with Age, Sex and Season in the Kars Province During the COVID-19 Pandemic

Abstract

Aim: This study aimed to determine the effect of the COVID-19 pandemic on changes in serum vitamin D levels (by age, sex, and season) of patients residing in Kars province during the pandemic and to detect whether vitamin D supplementation was needed during this period. Materials and Methods: In this study, a retrospective evaluation of laboratory results available in the hospital automation system of the Kafkas University Health Application and Research Center was planned. Results: The study included 14,054 laboratory results of patients admitted to the Training and Research Hospital of Kafkas University from 01.01.2020 to 31.12.2021. Of these results, 8925 (63.5%) were from women, and 5129 (36.5%) were from men. No statistically significant difference was observed in serum vitamin levels between the COVID-19 pandemic and the non-pandemic period. The 25-hydroxyvitamin D levels of women were lower than those of men during the pandemic. When assessed for seasonality, compared with summer and autumn, the patients’ 25-hydroxyvitamin D levels were significantly lower in winter and spring. Conclusion: The fact that the vitamin D levels of the patients in our study were shown to be close to the lower reference limit (20 ng/mL) suggests that, in the event of a pandemic, individuals may develop vitamin D deficiency and need vitamin supplementation. Given the effects of vitamin D deficiency and the associated health risks, further research and increased public awareness are needed. This study is expected to provide reference data for future research and to contribute to national and international scientific literature by offering insights on how to protect public health and raise public awareness.

Keywords

• age
• sex
• season
• vitamin D; covid 19

References

1. 1. Feyzioğlu B. The origin of SARS-CoV-2. J Biotechnol and Strategic Health Res. 2020;1(Special Issue):1–9.
2. 2. Liu Y, Gayle AA, Wilder Smith A, Rocklöv J. The reproductive number of COVID-19 is higher compared to SARS coronavirus. J Travel Med. 2020;27(2):1–4.
3. 3. Şener Cömert S, Kıral N. COVID-19 Radiological findings of pneumonia. South. Clin. Ist. Euras. 2020;31(Suppl) :16–22.
4. 4. Şimşek AÇ, Kara A, Baran Aksakal FN, Gülüm M, İlter B, Ender L, et al. Contact tracing management of the COVID-19 pandemic. Turk Hij Den Biyol Derg. 2020;77(3):269–80.
5. 5. Radlović N, Mladenović M, Simić D, Radlović P. Vitamin D in the light of current knowledge. Srp Arh Celok Lek. 2012;140(12):110–4.
6. 6. Grant WB and Boucher BJ. Requirements for vitamin D across the life span [abstract]. Biol Res Nurs. 2011;13(2):120–33.
7. 7. Köksal M, Gürel Köksal N, Sağlam Z. A. Evaluation of the relationship between vitamin D levels and insulin resistance in adults. Bozok Med J. 2023;13(1):129–35.
8. 8. Olerod G. The variation in free 25-hydroxy vitamin D and vitamin D-binding protein with season and vitamin D status. Endocr Connect. 2017;6(2):111–20.

9. 9. Horváth L, Mirani S, Girgis MMF, Rácz S, Bácskay I, Bhattoa HP, et al. Six years’ experience and trends of serum 25-hydroxy vitamin D concentration and the effect of vitamin D3 consumption on these trends. Front. Pharmacol. 2023;14:1–16.
10. 10. Laird E, Walsh JB, Lanham-New S, O’Sullivan M, Kenny RA, Scully H, et al. A high prevalence of vitamin D deficiency observed in an Irish Southeast Asian population a crosssectional observation study. Nutrients. 2020;12(12):3674.
11. 11. Gholami Z, Sert H. The Relationship of Vitamin D deficiency and obesity with coronavirus disease infection. SAUHSD. 2022;5(1):76–84.
12. 12. Li Y, Tong CH, Bare LA, Devlin JJ. Assessment of the association of vitamin D level with SARS-CoV-2 seropositivity among working-age adults. JAMA Netw Open. 2021;4(5):e2111634.
13. 13. Santaolalla A, Beckmann K, Kibaru J, Josephs D, Hemelrijck MV, Irshad S. Association between vitamin D and novel SARSCoV-2 respiratory dysfunction - a scoping review of current evidence and its implication for COVID-19 pandemic. Front Physiol. 2020;26(11):564387.
14. 14. Okan S, Okan F, Demir O. Association of vitamin D level with age, gender, living place and season of the year in children and adolescents. J Health Sci. 2020;29(2):114–8.
15. 15. Tahiroğlu V and Alayunt NÖ. Changes in vitamin D levels according to age, gender and seasons in Şırnak province. Turk J Osteoporos. 2023;29(1):17–21.
16. 16. Özdin M ve Mundan D. Examining of vitamin D levels in children in terms of some factors. ASUJMS. 2022:3(2):13–7. (cited 2025 April 19)Available form: https://dergipark. org. tr/ en/download/article-file/2324160.
17. 17. Kaytaz M, Eroğlu İçli H, Akkaya E, Ademoğlu E, Genç S. Alterations in 25(OH) vitamin D concentrations and seasonal differences according to age groups in Turkey. Nobel Med. 2022;18(3):161–6. (cited 2025 April 19) Available from: https://www. nobelmedicus. com/Content/ journal/54/161–166. pdf
18. 18. Kazemi A, Mohammadi V, Aghababaee SK. Golzarand M, Clark CC, Babajafari S. Association of vitamin D status with SARS-CoV-2 infection or COVID-19 severity: A systematic review and metaanalysis. Adv Nutr. 2021;12(5):1636–58.
19. 19. Rachman A, Rahmaniyah R, Khomeini A, Iriani A. The association between vitamin D deficiency and the clinical outcomes of hospitalized COVID-19 patients. F1000Res. 2024;5(12):394.
20. 20. Pereira M, Dantas Damascena A, Galvão Azevedo LM, de Almeida Oliveira T, da Mota Santana J. Vitamin D deficiency aggravates COVID-19: systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2022;62(5):1308–16.
21. 21. Lie PC, Stefanescu S, Smith L. The role of vitamin D in the prevention of coronavirus disease 2019 infection and mortality. Aging Clin Exp Res. 2020;32(7):1195–8.
22. 22. Ali N. Role of vitamin D in preventing of COVID-19 infection, progression and severity. J Infect. Public Health. 2020;13:1373–80.
23. 23. Davran F, Hacioğlu C, Kayabaşı E, Keskin BH, Duran P, Unlu EN, et al. The effect of vitamin D level on the clinical situation in covid-19 patients. Konuralp Medical Journal. 2023;15(1):130–5.
24. 24. Abdollahi A, Sarvestani HK, Rafat Z, Ghaderkhani S, Mahmoudi‐Aliabadi M, Jafarzadeh B. The association between the level of serum 25(OH) vitamin D, obesity, and underlying diseases with the risk of developing COVID‐19 infection: A case-control study of hospitalized patients in Tehran, Iran. J Med Virol. 2020;1–6.
25. 25. Campi I, Gennari L, Merlotti D. Vitamin D and COVID-19 severity and related mortality: A prospective study in Italy. BMC Infect Dis. 2021;21(1):566.
26. 26. AlSafar H, Grant WB, Hijazi R, Uddin M, Alkaabi N, Tay G, et al. COVID-19 disease severity and death in relation to vitamin D status among SARS-CoV-2-positive UAE residents. Nutrients. 2021;13(5):1714.
27. 27. Takase T, Tsugawa N, Sugiyama T, Ikesue H, Eto M, Hashida T, et al. Association between 25-hydroxyvitamin D levels and COVID-19 severity. Clin Nutr ESPEN. 2022;49:256–63.
28. 28. Karahan S and Katkat F. Impact of serum 25(OH) vitamin D level on mortality in patients with Covid-19 in Turkey. J Nutr Health Aging. 2021;25(2):189–96.
29. 29. Grant WB, Lahore H, McDonnell SL, Baggerly CA, French CB, Aliano JL, et al. Evidence that vitamin D supplementation could reduce risk of influenza and COVID-19 infections and deaths. Nutrients. 2020;12(4):988.
30. 30. Martineau AR, Jolliffe DA, Hooper RL, Greenberg L, Aloia JF, Bergman P, et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ. 2017;356:i6583