BIOCHEMICAL AND PHYSIOLOGICAL EFFECTS OF VITAMIN D SUPPLEMENTATION ON IMMUNE RESPONSE IN CHILDREN WITH RECURRENT RESPIRATORY INFECTIONS
Main Article Content
Keywords
Vitamin D, recurrent respiratory infections, children, immune response, cytokines, inflammation
Abstract
Background: Recurrent respiratory infections (RRIs) are a common health problem in children and are associated with significant morbidity. Vitamin D is known to play an important role in immune regulation, and its deficiency has been linked with increased susceptibility to infections.
Objective: To assess the association between vitamin D status and biochemical and physiological immune responses in children with recurrent respiratory infections.
Methods: This analytical cross-sectional study was conducted at Rehman Medical Institute, Peshawar, from January 2024 to January 2025. A total of 72 children aged 2–12 years with recurrent respiratory infections were included using a non-probability consecutive sampling technique. Serum 25-hydroxyvitamin D [25(OH)D] levels were measured and categorized as deficient, insufficient, and sufficient. Biochemical markers including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), immunoglobulin A (IgA), and immunoglobulin G (IgG) were assessed using ELISA. Data were analyzed using SPSS version 25.0, and correlations were determined using Pearson’s test.
Results: Vitamin D deficiency was observed in 66.7% of participants. Lower vitamin D levels were significantly associated with higher levels of CRP, IL-6, and TNF-α (p<0.001). A positive association was found between vitamin D levels and immunoglobulin levels (IgA and IgG). Children with lower vitamin D levels had a higher frequency of infection episodes and increased antibiotic use. A significant negative correlation was observed between vitamin D levels and infection frequency (r = -0.62, p<0.001).
Conclusion: Vitamin D deficiency is common in children with recurrent respiratory infections and is associated with increased inflammation and impaired immune response. Assessment of vitamin D status may be important in the clinical evaluation of these children.
References
2. Bleakley, A.S., P.V. Licciardi, and M.J.J.N. Binks, Vitamin D modulation of the innate immune response to paediatric respiratory pathogens associated with acute lower respiratory infections. 2021. 13(1): p. 276.
3. Marusca, L.M., et al., The effects of vitamin D supplementation on respiratory infections in children under 6 years old: a systematic review. 2023. 11(3): p. 104.
4. Mailhot, G. and J.H.J.N. White, Vitamin D and immunity in infants and children. 2020. 12(5): p. 1233.
5. Charoenngam, N. and M.F.J.N. Holick, Immunologic effects of vitamin D on human health and disease. 2020. 12(7): p. 2097.
6. Johnson, C.R., T.D.J.P. Thacher, and I.C. Health, Vitamin D: immune function, inflammation, infections and auto-immunity. 2023. 43(4): p. 29-39.
7. Vaghari-Tabari, M., et al., Vitamin D in respiratory viral infections: a key immune modulator? 2023. 63(14): p. 2231-2246.
8. Fabbri, A., M. Infante, and C.J.E.R.M.P.S. Ricordi, Editorial-Vitamin D status: a key modulator of innate immunity and natural defense from acute viral respiratory infections. 2020. 24(7): p. 4048-4052.
9. Siddiqui, M., et al., Immune modulatory effects of vitamin D on viral infections. 2020. 12(9): p. 2879.
10. Wimalawansa, S.J.J.N., Infections and autoimmunity—the immune system and vitamin D: a systematic review. 2023. 15(17): p. 3842.
11. Sun, M., et al., Dynamic monitoring and a clinical correlation analysis of the serum vitamin A, D, and E levels in children with recurrent respiratory tract infections. 2022. 14(5): p. 3533.
12. Ganmaa, D., et al., Vitamin D, respiratory infections, and chronic disease: Review of meta‐analyses and randomized clinical trials. 2022. 291(2): p. 141-164.
13. Sanlier, N. and M.J.E.P.A.G. Guney-Coskun, Vitamin D, the immune system, and its relationship with diseases. 2022. 70(1): p. 39.
14. Musavi, H., et al., The benefits of Vitamin D in the COVID-19 pandemic: biochemical and immunological mechanisms. 2023. 129(2): p. 354-362.
15. Sîrbe, C., et al., An update on the effects of vitamin D on the immune system and autoimmune diseases. 2022. 23(17): p. 9784.
16. Pecora, F., et al., The role of micronutrients in support of the immune response against viral infections. 2020. 12(10): p. 3198.
17. Cheng, C., et al., Clinical effect of vitamin D supplementation on patients with pulmonary tuberculosis and its influence on the expression of immune cells and inflammatory factors. 2020. 20(3): p. 2236-2244.
18. Ghaseminejad-Raeini, A., et al., Immunomodulatory actions of vitamin D in various immune-related disorders: A comprehensive review. 2023. 14: p. 950465.
19. Abdelkader, A., et al., Recurrent respiratory infections and vitamin A levels: a link? It is cross-sectional. 2022. 101(33): p. e30108.
20. Ao, T., J. Kikuta, and M.J.B. Ishii, The effects of vitamin D on immune system and inflammatory diseases. 2021. 11(11): p. 1624.

