Vitamin D supplementation and enhanced immune response

Vitamin D increases immunity

Vitamin D supplementation and enhanced immune response

Vitamin D supplementation and enhanced immune response

·        Most elderly population are characterized by elevated levels of blood biomarkers that carries high susceptibility to chronic morbidity, disability, frailty and pre mature death  – concept termed as inflammageing1. Deficiencies of micronutrients pre dispose to further immunity challenges to elderly population. A major association, which has been established decrease immune response to infections leading greater incidences in elderly, is with Vitamin D. Thus, it was hypothesized that individuals with sufficient vitamin D levels will show improved immune response than vitamin D deficient individuals.

·        A study2 reported the use of vitamin D3 replacement to enhance cutaneous antigen-specific immunity in older adults (≥65 years). Vitamin D insufficient older adults (n = 18) were administered 6400IU of vitamin D3/day orally for 14 weeks. Antigen-specific immunity to VZV was assessed by clinical score assessment of the injection site and transcriptional analysis of skin biopsies collected from challenged injection sites pre- and post-vitamin D3 replacement. It was found that older adults had reduced VZV-specific cutaneous immune response and increased non-specific inflammation as compared to young. Increased non-specific inflammation observed in the skin of older adults negatively correlated with vitamin D sufficiency. Vitamin D3 supplementation significantly increased the response to cutaneous VZV antigen challenge in elderly population. The results of this study are indicative of a probable role of immunomodulatory action of vitamin D in combating other viral infections like COVID 19.

·        Old age is an independent risk factor for VD deficiency. The supplementary dose of VD should be precisely defined to achieve the optimal serum 25(OH) D level in elderly people. A study3 reported that no Vitamin D supplement treatment was given to more than 75% of patients during the preceding 3 years. Results from recent clinical trials4 done during the present COVID 19 pandemic confirms that 25OH-vitamin D serum deficiency is associated with more severe lung involvement, longer disease duration and risk of death, in elderly COVID-19 patients. Institutionalized older adults are inherently at risk of vitamin D deficiency because of a lack of sun exposure and dietary insufficiency and may have worse outcomes with COVID-19. As our nation’s older adult population continues to grow, establishing universal guidelines for testing and treating vitamin D deficiency is needed especially to combat COVID 19.

References

1.      Ferrucci L, Fabbri E. Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty. Nat Rev Cardiol. 2018;15(9):505-522

2.      Chambers E S et al; Vitamin D3 replacement enhances antigen-specific immunity in older adults. Immunotherapy Advances, 2021, Vol. 1, No. 1, 1–13

3.      Kweder H, Eidi H. Vitamin D deficiency in elderly: Risk factors and drugs impact on vitamin D status. Avicenna J Med. 2018;8(4):139-146

4.      Sulli A, Gotelli E, Casabella A, Paolino S, Pizzorni C, Alessandri E, Grosso M, Ferone D, Smith V, Cutolo M. Vitamin D and Lung Outcomes in Elderly COVID-19 Patients. Nutrients. 2021 Feb 24;13(3):717. doi: 10.3390/nu13030717