Vitamin D to Relieve Severe Symptoms Due to Covid 19
The COVID-19 pandemic has claimed hundreds of thousands of lives worldwide. This severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection represents a broad spectrum of disease, with most patients experiencing mild or even asymptomatic symptoms.
Large variations in COVID-19 mortality rates between countries and regions have been reported. In addition to age, comorbid diseases, and availability of health facilities; Vitamin D adequacy status is assumed to play a role, considering that the COVID-19 mortality rate was found to be relatively higher in countries with a high incidence of vitamin D deficiency, such as Italy, Spain, and France.
In addition, the timing of the COVID-19 pandemic which coincides with winter, when vitamin D levels are at their lowest, also supports the potential involvement of vitamin D in reducing the risk of COVID-19.
The Role of Vitamin D in Modulating the Immune System
Vitamin D inhibits the expression and reduces transcription of several proinflammatory cytokines. On the other hand, vitamin D also increases T helper cytokines which are anti-inflammatory. This vitamin also has a potent antiproliferative effect on T cells, particularly helper T cells, and decreases the production of B cell antibodies.
The important role of vitamin D3 as an immune regulator is not only due to its interaction with T lymphocyte cells, but also its interaction with antigen-presenting cells (APCs).
Monocytes exposed to vitamin D3 will reduce major histocompatibility complex (MHC) class II. Ultimately, vitamin D will inhibit the release of proinflammatory cytokines by macrophages and upregulate antimicrobial peptides that have antiviral potential.
Vitamin D also reduces the inflammatory response to SARS-CoV-2 infection, where vitamin D is able to interact with the protein angiotensin-converting-enzyme 2 (ACE2) as a receptor for the entry of the SARS-CoV-2 virus.
The Role of Vitamin D in Various Respiratory Diseases
In addition to its role in bone health and calcium homeostasis, there is ample evidence that vitamin D plays a role in the prevention and treatment of various respiratory infectious diseases, such as pulmonary tuberculosis and influenza.
In a meta-analysis conducted by Nnoaham et al, it was suggested that low levels of vitamin D3 are associated with susceptibility to infection with more severe active pulmonary tuberculosis.
Role of Vitamin D in COVID-19 Infection
Vitamin D has been shown to lower the risk of respiratory tract infections. At the same time, its effect on enhancing cellular and adaptive immunity also makes vitamin D worthy of consideration as a potential option to treat and prevent COVID-19.
To date, no clinical trials have been conducted to determine the effect of vitamin D specifically in suppressing the SARS-CoV-2 chain. Several studies have examined the clinical outcomes of COVID-19 patients based on vitamin D status.
A meta-analysis conducted by Alipio examined 212 COVID-19 patients and their vitamin D status. The mean serum vitamin D level was 31.2 g/mL in mild symptoms; 27.4 g/ml at moderate symptoms; and 21.2 g/ml in severe symptoms.
Normal vitamin D levels were found in 55 patients and the majority (85.5%) experienced mild symptoms. Vitamin D insufficiency status was found in 80 patients and the majority (43.8%) had moderate symptoms. There were 77 patients with vitamin D deficiency status and the majority (40.3%) experienced severe symptoms.
This study concludes that serum vitamin D levels are associated with clinical outcomes of COVID-19 patients. In this regard, vitamin D supplementation may improve the clinical outcome of COVID-19 patients, but large-sample randomized controlled clinical trials are needed to confirm this.
A retrospective cohort study in Indonesia, with a sample of 780 COVID-19 patients, investigated the association between vitamin D status and mortality in COVID-19 patients.
After ruling out confounding factors, such as age, gender, and comorbidities; The results of this study conclude that vitamin D status is closely related to mortality in COVID-19 patients. The mortality rate was found to be higher in patients with vitamin D insufficiency.
When compared with COVID-19 patients with normal vitamin D status, the risk of death increased by 10.12 times in COVID-19 patients with vitamin D deficiency.
In a narrative review, Grant et al support the role of high concentrations of vitamin D in lowering the risk of acute respiratory tract infections (ARI), including influenza, pneumonia, and coronavirus infections.
Vitamin D3 supplementation can be given to increase the concentration of vitamin D. The optimal range of vitamin D to achieve a protective effect is 40-60 g/mL.
To achieve these levels, vitamin D3 supplementation needs to be given at a dose of 10,000 IU per day for a month, then followed by a dose of 5,000 IU per day. If high doses of vitamin D are given, calcium supplementation does notmay be given in high doses to avoid hyperkalemia.
On the other hand, the National Heart, Lung and Blood Institute (NHBLI) conducted a randomized controlled trial and concluded that high-dose vitamin D3 supplementation does not provide a greater benefit than placebo on the mortality of critically ill patients with vitamin D deficiency.
Therefore, it is recommended to provide vitamin D supplementation according to standard daily nutritional needs.