Does Vitamin D impact COVID-19 prevention and treatment?

Vitamin D is an immunomodulator hormone with an anti-inflammatory and antimicrobial effect with a high safety profile. A lot of COVID-19 infected patients develop acute respiratory distress syndrome (ARDS), which may lead to multiple organ damage. These symptoms are associated with a cytokine storm syndrome. The aim of this letter is to note the 5 crucial points that vitamin D could have protective and therapeutic effects against COVID-19. For that reason, COVID-19 infection-induced multiple organ damage might be prevented by vitamin D.

Vitamin D can prevent COVID-19 infection-induced multiple organ damage

The outbreak of COVID-19 has created a global public health crisis. Little is known about the protective factors of this infection. Therefore, preventive health measures that can reduce the risk of infection, progression and severity are desperately needed. This review discussed the possible roles of vitamin D in reducing the risk of COVID-19 and other acute respiratory tract infections and severity. Moreover, this study determined the correlation of vitamin D levels with COVID-19 cases and deaths in 20 European countries as of 20 May 2020. A significant negative correlation (p = 0.033) has been observed between mean vitamin D levels and COVID-19 cases per one million population in European countries. However, the correlation of vitamin D with COVID-19 deaths of these countries was not significant. Some retrospective studies demonstrated a correlation between vitamin D status and COVID-19 severity and mortality, while other studies did not find the correlation when confounding variables are adjusted. Several studies demonstrated the role of vitamin D in reducing the risk of acute viral respiratory tract infections and pneumonia. These include direct inhibition with viral replication or with anti-inflammatory or immunomodulatory ways. In the meta-analysis, vitamin D supplementation has been shown as safe and effective against acute respiratory tract infections. Thus, people who are at higher risk of vitamin D deficiency during this global pandemic should consider taking vitamin D supplements to maintain the circulating 25(OH)D in the optimal levels 75-125 nmol/L. In conclusion, there not enough evidence on the association between vitamin D levels and COVID-19 severity and mortality. Therefore, randomized control trials and cohort studies are necessary to test this hypothesis.

Role of vitamin D in preventing of COVID-19 infection, progression and severity

The outbreak of COVID-19 has created a global public health crisis. Little is known about the protective factors of this infection. Therefore, preventive health measures that can reduce the risk of infection, progression and severity are desperately needed. This review discussed the possible roles of vitamin D in reducing the risk of COVID-19 and other acute respiratory tract infections and severity. Moreover, this study determined the correlation of vitamin D levels with COVID-19 cases and deaths in 20 European countries as of 20 May 2020. A significant negative correlation (p=0.033) has been observed between mean vitamin D levels and COVID-19 cases per one million population in European countries. However, the correlation of vitamin D with COVID-19 deaths of these countries was not significant. Some retrospective studies demonstrated a correlation between vitamin D status and COVID-19 severity and mortality, while other studies did not find the correlation when confounding variables are adjusted. Several studies demonstrated the role of vitamin D in reducing the risk of acute viral respiratory tract infections and pneumonia. These include direct inhibition with viral replication or with anti-inflammatory or immunomodulatory ways. In the meta-analysis, vitamin D supplementation has been shown as safe and effective against acute respiratory tract infections. Thus, people who are at higher risk of vitamin D deficiency during this global pandemic should consider taking vitamin D supplements to maintain the circulating 25(OH)D in the optimal levels (75-125nmol/L). In conclusion, there is not enough evidence on the association between vitamin D levels and COVID-19 severity and mortality. Therefore, randomized control trials and cohort studies are necessary to test this hypothesis.

Epidemiological data report that several countries with a high prevalence of hypovitaminosis D may have increased susceptibility to complications and mortality due to COVID-19 infection. These reports, however, have limitations given that they derive from observational studies. Nevertheless, while awaiting more robust data, clinicians should treat patients with vitamin D deficiency irrespective of whether or not it has a link with respiratory infections.

Vitamin D and COVID-19

Comments on: The role of vitamin D in the prevention of coronavirus disease 2019 infection and mortality

The study discusses the possible role of adequate vitamin D status in plasma or serum for preventing acute respiratory infections during the Covid-19 pandemic. Our arguments respond to an article, published in Italy, that describes the high prevalence of hypovitaminosis D in older Italian women and raises the possible preventive and therapeutic role of optimal vitamin D levels. Based on literature review, we highlight the findings regarding the protective role of vitamin D for infectious diseases of the respiratory system. However, randomized controlled trials are currently lacking. Adequate vitamin D status is obtained from sun exposure and foods rich in vitamin D. Studies in Brazil have shown that hypovitaminosis D is quite common in spite of high insolation. Authors recommend ecological, epidemiological and randomized controlled trials studies to verify this hypothesis.

Does Vitamin D play a role in the management of Covid-19 in Brazil?

Coronavirus infection is a serious health problem awaiting an effective vaccine and/or antiviral treatment. The major complication of coronavirus disease 2019 (COVID-19), the Acute Respiratory Distress syndrome (ARDS), is due to a variety of mechanisms including cytokine storm, dysregulation of the renin-angiotensin system, neutrophil activation and increased (micro)coagulation. Based on many preclinical studies and observational data in humans, ARDS may be aggravated by vitamin D deficiency and tapered down by activation of the vitamin D receptor. Several randomized clinical trials using either oral vitamin D or oral Calcifediol (25OHD) are ongoing. Based on a pilot study, oral calcifediol may be the most promising approach. These studies are expected to provide guidelines within a few months.

Vitamin D receptor stimulation to reduce acute respiratory distress syndrome (ARDS) in patients with coronavirus SARS-CoV-2 infections: Revised Ms SBMB 2020_166

Vitamin D Receptor stimulation to reduce Acute Respiratory Distress Syndrome (ARDS) in patients with Coronavirus SARS-CoV-2 infections: Revised Ms SBMB 2020_166

Coronavirus disease (COVID-19) is a major pandemic and now a leading cause of death worldwide. Currently, no drugs/vaccine is available for the treatment of this disease. Future preventions and social distancing are the only ways to prevent this disease from community transmission. Vitamin D is an important micronutrient and has been reported to improve immunity and protect against respiratory illness. This short review highlights the important scientific link between Vit D levels and susceptibility to COVID-19 in patients. This review also discusses recommendations for Vit D dose required for healthy as well as COVID-19 susceptible patients for protection and prevention.

Vitamin D Levels and COVID-19 Susceptibility: Is there any Correlation?

Vitamin D Supplementation: A Potential Approach for Coronavirus/COVID-19 Therapeutics?

COVID-19 and vitamin D—Is there a link and an opportunity for intervention?

COVID-19 and vitamin D-Is there a link and an opportunity for intervention?

Perspective: improving vitamin D status in the management of COVID-19

Coronavirus 2019 disease (COVID-19) mostly adversely affects the elderly, a population at higher risk for low serum 25-hydroxyvitamin D (25(OH)D) levels. In this viewpoint, we highlight the well-known musculoskeletal properties of vitamin D, which are particularly relevant in the context of COVID-19, suggesting further potential benefits through extra-skeletal effects. Maintaining optimal 25(OH)D is crucial to prevent falls, frailty and fractures in elderly patients, with low activity levels due to lockdown, or who are relatively immobilized during hospitalization and after discharge for prolonged periods of time. Hypovitaminosis D is also associated with susceptibility to respiratory infections, admissions to the intensive care unit, and mortality. We underscore the importance of achieving desirable serum 25(OH)D in COVID-19 elderly patients, to ensure beneficial musculoskeletal effects and possibly respiratory effects of vitamin D, in the context of COVID-19.

The D-side of COVID-19: musculoskeletal benefits of vitamin D and beyond

• Vitamin D deficiency is very frequent. • Controlled trials showed that vitamin D decreases acute respiratory infections. • Despite a lack of direct evidence of an effect of vitamin D on COVID-19 infection. • Daily vitamin D supplementation with moderate doses is safe and cheap. • Even a small decrease in COVID-19 infections would easily justify this intervention.

Vitamin D deficiency and COVID-19 pandemic

The severity of coronavirus 2019 infection (COVID-19) is determined by the presence of pneumonia, severe acute respiratory distress syndrome (SARS-CoV-2), myocarditis, microvascular thrombosis and/or cytokine storms, all of which involve underlying inflammation. A principal defence against uncontrolled inflammation, and against viral infection in general, is provided by T regulatory lymphocytes (Tregs). Treg levels have been reported to be low in many COVID-19 patients and can be increased by vitamin D supplementation. Low vitamin D levels have been associated with an increase in inflammatory cytokines and a significantly increased risk of pneumonia and viral upper respiratory tract infections. Vitamin D deficiency is associated with an increase in thrombotic episodes, which are frequently observed in COVID-19. Vitamin D deficiency has been found to occur more frequently in patients with obesity and diabetes. These conditions are reported to carry a higher mortality in COVID-19. If vitamin D does in fact reduce the severity of COVID-19 in regard to pneumonia/ARDS, inflammation, inflammatory cytokines and thrombosis, it is our opinion that supplements would offer a relatively easy option to decrease the impact of the pandemic.

Does vitamin D deficiency increase the severity of COVID-19?

Reply to Jakovac: “COVID-19 and vitamin D—Is there a link and an opportunity for intervention?”

Vitamin D and COVID-19

We thank Kumar et al for their comments on our review article and the letter connected with that by Panarese and Shahini.(1,2) We agree that there is a complicated effect of vitamin D in preventing the severity of COVID‐19, while this mechanism is not exactly the same as that of influenza.

Letter: does vitamin D have a potential role against COVID‐19? Authors' reply

Letter: Covid-19, and vitamin D. Authors' reply

WHO declared SARS-CoV-2 a global pandemic. The present aim was to propose an hypothesis that there is a potential association between mean levels of vitamin D in various countries with cases and mortality caused by COVID-19. The mean levels of vitamin D for 20 European countries and morbidity and mortality caused by COVID-19 were acquired. Negative correlations between mean levels of vitamin D (average 56 mmol/L, STDEV 10.61) in each country and the number of COVID-19 cases/1 M (mean 295.95, STDEV 298.7, and mortality/1 M (mean 5.96, STDEV 15.13) were observed. Vitamin D levels are severely low in the aging population especially in Spain, Italy and Switzerland. This is also the most vulnerable group of the population in relation to COVID-19. It should be advisable to perform dedicated studies about vitamin D levels in COVID-19 patients with different degrees of disease severity.

The role of vitamin D in the prevention of coronavirus disease 2019 infection and mortality

Letter: does vitamin D have a potential role against COVID-19? Authors' reply

PURPOSE: Covid-19 is a pandemic of unprecedented proportion, whose understanding and management is still under way. In the emergency setting new or available therapies to contrast the spread of COVID-19 are urgently needed. Elderly males, especially those affected by previous diseases or with comorbidities, are more prone to develop interstitial pneumonia that can deteriorate evolving to ARDS (acute respiratory distress syndrome) that require hospitalization in Intensive Care Units (ICUs). Even children and young patients are not spared by SARS-CoV 2 infection, yet they seem to develop a milder form of disease. In this setting the immunomodulatory role of Vitamin D, should be further investigated. METHODS: We reviewed the literature about the immunomodulatory role of Vitamin D collecting data from the databases Medline and Embase. RESULTS: Vitamin D proved to interact both with the innate immune system, by activating Toll-like receptors (TLRs) or increasing the levels of cathelicidins and ß-defensins, and adaptive immune system, by reducing immunoglobulin secretion by plasma cells and pro-inflammatory cytokines production, thus modulating T cells function. Promising results have been extensively described as regards the supplementation of vitamin D in respiratory tract infections, autoimmune diseases and even pulmonary fibrosis. CONCLUSIONS: In this review, we suggest that vitamin D supplementation might play a role in the prevention and/or treatment to SARS-CoV-2 infection disease, by modulating the immune response to the virus both in the adult and pediatric population.

Possible role of vitamin D in Covid-19 infection in pediatric population

Vitamin D and Covid-19: A Note of Caution.

PURPOSE: Covid-19 is a pandemic of unprecedented proportion, whose understanding and management is still under way. In the emergency setting new or available therapies to contrast the spread of COVID-19 are urgently needed. Elderly males, especially those affected by previous diseases or with comorbidities, are more prone to develop interstitial pneumonia that can deteriorate evolving to ARDS (acute respiratory distress syndrome) that require hospitalization in Intensive Care Units (ICUs). Even children and young patients are not spared by SARS-CoV 2 infection, yet they seem to develop a milder form of disease. In this setting the immunomodulatory role of Vitamin D, should be further investigated. Methods: We reviewed the literature about the immunomodulatory role of Vitamin D collecting data from the databases Medline and Embase. RESULTS: Vitamin D proved to interact both with the innate immune system, by activating Toll-like receptors (TLRs) or increasing the levels of cathelicidins and β-defensins, and adaptive immune system, by reducing immunoglobulin secretion by plasma cells and pro-inflammatory cytokines production, thus modulating T cells function. Promising results have been extensively described as regards the supplementation of vitamin D in respiratory tract infections, autoimmune diseases and even pulmonary fibrosis. CONCLUSIONS: In this review, we suggest that vitamin D supplementation might play a role in the prevention and/or treatment to SARS-CoV-2 infection disease, by modulating the immune response to the virus both in the adult and pediatric population.

Vitamin D and SARS-CoV-2 virus/COVID-19 disease

Vitamin d and covid-19: A note of caution

The world is in the grip of the COVID-19 pandemic. Public health measures that can reduce the risk of infection and death in addition to quarantines are desperately needed. This article reviews the roles of vitamin D in reducing the risk of respiratory tract infections, knowledge about the epidemiology of influenza and COVID-19, and how vitamin D supplementation might be a useful measure to reduce risk. Through several mechanisms, vitamin D can reduce risk of infections. Those mechanisms include inducing cathelicidins and defensins that can lower viral replication rates and reducing concentrations of pro-inflammatory cytokines that produce the inflammation that injures the lining of the lungs, leading to pneumonia, as well as increasing concentrations of anti-inflammatory cytokines. Several observational studies and clinical trials reported that vitamin D supplementation reduced the risk of influenza, whereas others did not. Evidence supporting the role of vitamin D in reducing risk of COVID-19 includes that the outbreak occurred in winter, a time when 25-hydroxyvitamin D (25(OH)D) concentrations are lowest; that the number of cases in the Southern Hemisphere near the end of summer are low; that vitamin D deficiency has been found to contribute to acute respiratory distress syndrome; and that case-fatality rates increase with age and with chronic disease comorbidity, both of which are associated with lower 25(OH)D concentration. To reduce the risk of infection, it is recommended that people at risk of influenza and/or COVID-19 consider taking 10,000 IU/d of vitamin D3 for a few weeks to rapidly raise 25(OH)D concentrations, followed by 5000 IU/d. The goal should be to raise 25(OH)D concentrations above 40-60 ng/mL (100-150 nmol/L). For treatment of people who become infected with COVID-19, higher vitamin D3 doses might be useful. Randomized controlled trials and large population studies should be conducted to evaluate these recommendations.

Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths

Background Recent research has indicated that vitamin D may have immune supporting properties through modulation of both the adaptive and innate immune system through cytokines and regulation of cell signalling pathways. We hypothesize that vitamin D status may influence the severity of responses to Covid-19 and that the prevalence of vitamin D deficiency in Europe will be closely aligned to Covid-19 mortality. Methods We conducted a literature search on PubMed (no language restriction) of vitamin D status (for older adults) in countries/areas of Europe affected by Covid-19 infection. Countries were selected by severity of infection (high and low) and were limited to national surveys or where not available, to geographic areas within the country affected by infection. Covid-19 infection and mortality data was gathered from the World Health Organisation. Results Counter-intuitively, lower latitude and typically 'sunny' countries such as Spain and Italy (particularly Northern Italy), had low mean concentrations of 25(OH)D and high rates of vitamin D deficiency. These countries have also been experiencing the highest infection and death rates in Europe. The northern latitude countries (Norway, Finland, Sweden) which receive less UVB sunlight than Southern Europe, actually had much higher mean 25(OH)D concentrations, low levels of deficiency and for Norway and Finland, lower infection and death rates. The correlation between 25(OH)D concentration and mortality rate reached conventional significance (P=0.046) by Spearman's Rank Correlation. Conclusions Optimising vitamin D status to recommendations by national and international public health agencies will certainly have benefits for bone health and potential benefits for Covid-19. There is a strong plausible biological hypothesis and evolving epidemiological data supporting a role for vitamin D in Covid-19.

Vitamin D and Inflammation: Potential Implications for Severity of Covid-19.

Vitamin D deficiency and insufficiency (VDD) are widely recognized as risk factors for respiratory tract infections. Vitamin D influences expression of many genes with well-established relevance to airway infections and relevant to immune system function. Recently, VDD has been shown to be a risk factor for acquisition and severity of COVID-19. Thus, treating VDD presents a safe and inexpensive opportunity for modulating the severity of the disease. VDD is common in those over 60 years of age, many with co-morbid conditions and in people with skin pigmentation sufficient to reduce synthesis of vitamin D. Exposure to fine particulate air pollution is also associated with worse outcomes from COVID19. Vitamin D stimulates transcription of cathelicidin which is cleaved to generate LL37. LL37 is an innate antimicrobial with demonstrated activity against a wide range of microbes including envelope viruses. LL37 also modulates cytokine signaling at the site of infections. Fine particles in air pollution can interfere with LL37 destruction of viruses and may reduce effective immune signaling modulation by LL37. While vitamin D influences transcription of many immune related genes, the weakened antimicrobial response of those with VDD against SARS-CoV-2 may be in part due to reduced LL37. Conclusion: Vitamin D plays an important role reducing the impact of viral lung disease processes. VDD is an acknowledged public health threat that warrants population-wide action to reduce COVID-19 morbidity and mortality. While vitamin D influences transcription of many immune related genes, the weakened antimicrobial response of those with VDD against SARS-CoV-2 may be in part due to reduced LL37. Action is needed to address COVID-19 associated risks of air pollution from industry, transportation, domestic sources and from primary and second hand tobacco smoke.

Vitamin D Deficiency and Air Pollution Exacerbate COVID-19 Through Suppression of Antiviral Peptide LL37

There is an ongoing debate on the use of vitamin D supplementation in reducing the risk of influenza and COVID-19 infections and deaths. A recently published article highlights a relationship between vitamin D supplementation and reduced risk of COVID-19 and influenza. This comment aims to discuss the evidence on the use of Vitamin D in people who are at risk of developing COVID-19, focusing on safety issues of the Vitamin D supplementation.

Vitamin D Supplementation in Influenza and COVID-19 Infections Comment on: “Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths” Nutrients 2020, 12(4), 988

We thank Dr [...].

Reply: “Vitamin D Supplementation in Influenza and COVID-19 Infections. Comment on: Evidence That Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths Nutrients 2020, 12(4), 988”

Letter: Covid-19, and vitamin D

Letter: does vitamin D have a potential role against COVID-19?

Given the succession of communications in scientific and popular circuits, tending to take for granted a role for vitamin D in the control of the coronavirus pandemic, the authors conducted an analysis of the literature currently available in order to recognize what is supported by opinions personal and what evidence of effectiveness. At the end of the bibliographic survey there is the current absence of evidence of efficacy in favor of vitamin D in the treatment of coronavirus infection in its various expressions. The diffusion of personal opinions as if they were evidence can be a disturbing factor for adequate assistance and for correct research.

[Vitamin D and coronavirus: a new field of use?]

We thank Dr [...].

Reply: "Vitamin D Supplementation in Influenza and COVID-19 Infections. Comment on: Evidence That Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths Nutrients 2020, 12(4), 988"

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), with a clinical outcome ranging from mild to severe, including death. To date, it is unclear why some patients develop severe symptoms. Many authors have suggested the involvement of vitamin D in reducing the risk of infections; thus, we retrospectively investigated the 25-hydroxyvitamin D (25(OH)D) concentrations in plasma obtained from a cohort of patients from Switzerland. In this cohort, significantly lower 25(OH)D levels (p = 0.004) were found in PCR-positive for SARS-CoV-2 (median value 11.1 ng/mL) patients compared with negative patients (24.6 ng/mL); this was also confirmed by stratifying patients according to age >70 years. On the basis of this preliminary observation, vitamin D supplementation might be a useful measure to reduce the risk of infection. Randomized controlled trials and large population studies should be conducted to evaluate these recommendations and to confirm our preliminary observation.

25-Hydroxyvitamin D Concentrations Are Lower in Patients with Positive PCR for SARS-CoV-2

Vitamin D Supplementation in Influenza and COVID-19 Infections Comment on: "Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths" Nutrients 2020, 12(4), 988

The world is in the grip of the COVID-19 pandemic. Public health measures that can reduce the risk of infection and death in addition to quarantines are desperately needed. This article reviews the roles of vitamin D in reducing the risk of respiratory tract infections, knowledge about the epidemiology of influenza and COVID-19, and how vitamin D supplementation might be a useful measure to reduce risk. Through several mechanisms, vitamin D can reduce risk of infections. Those mechanisms include inducing cathelicidins and defensins that can lower viral replication rates and reducing concentrations of pro-inflammatory cytokines that produce the inflammation that injures the lining of the lungs, leading to pneumonia, as well as increasing concentrations of anti-inflammatory cytokines. Several observational studies and clinical trials reported that vitamin D supplementation reduced the risk of influenza, whereas others did not. Evidence supporting the role of vitamin D in reducing risk of COVID-19 includes that the outbreak occurred in winter, a time when 25-hydroxyvitamin D (25(OH)D) concentrations are lowest; that the number of cases in the Southern Hemisphere near the end of summer are low; that vitamin D deficiency has been found to contribute to acute respiratory distress syndrome; and that case-fatality rates increase with age and with chronic disease comorbidity, both of which are associated with lower 25(OH)D concentration. To reduce the risk of infection, it is recommended that people at risk of influenza and/or COVID-19 consider taking 10,000 IU/d of vitamin D(3) for a few weeks to rapidly raise 25(OH)D concentrations, followed by 5000 IU/d. The goal should be to raise 25(OH)D concentrations above 40–60 ng/mL (100–150 nmol/L). For treatment of people who become infected with COVID-19, higher vitamin D(3) doses might be useful. Randomized controlled trials and large population studies should be conducted to evaluate these recommendations.

Covid-19: Public health agencies review whether vitamin D supplements could reduce risk.

The authors have withdrawn this manuscript because they have noticed idiosyncrasies in the reporting of 25(OH)D data across different countries. Therefore, the authors do not wish this work to be cited until after this issue is addressed. If you have any questions, please contact the corresponding author.

The Role of Vitamin D in Suppressing Cytokine Storm in COVID-19 Patients and Associated Mortality

Vitamin-D and COVID-19: do deficient risk a poorer outcome?

Vitamin D supplementation in the COVID-19 pandemic

Optimisation of Vitamin D Status for Enhanced Immuno-protection Against Covid-19.

Letter: does vitamin D have a potential role against COVID‐19?

Background: Following emerge of a novel coronavirus from Wuhan, China, in December 2019, it has affected the whole world and after months of efforts by the medical communities, there is still no specific approach for prevention and treatment against the Coronavirus Disease 2019 (COVID-19). Evidence recommends that vitamin D might be an important supportive agent for the immune system, mainly in cytokine response regulation against COVID-19. Hence, we carried out a rapid systematic review and meta-analysis along with an ecological investigation in order to maximize the use of everything that exists about the role of vitamin D in the COVID-19. Methods: A systematic search was performed in PubMed, Scopus, Embase, Cochrane Library, Web of Science and Google Scholar (intitle) as well as preprint database of medRxiv, bioRxiv, Research Square, preprints.org, search engine of ScienceDirect and a rapid search through famous journals up to May 26, 2020. Studies focused on the role of vitamin D in confirmed COVID-19 patients were entered into the systematic review. Along with our main aim, to find the second objective: correlation of global vitamin D status and COVID-19 recovery and mortality we carried out a literature search in PubMed database to identify the national or regional studies reported the vitamin D status globally. CMA v. 2.2.064 and SPSS v.16 were used for data analysis. Results: Out of nine studies entered into our systematic review, six studies containing 3,822 participants entered into the meta-analysis. The meta-analysis indicated that 46.5% of COVID-19 patients were suffering from vitamin D deficiency (95% CI, 28.2%-65.8%) and in 43.3% of patients, levels of vitamin D were insufficient (95% CI, 27.4%-60.8%). In regard to our ecological investigation on 51 countries including 408,748 participants, analyses indicated no correlation between vitamin D levels and recovery rate (r= 0.041) as well as mortality rate (r=-0.073) globally. However, given latitude, a small reverse correlation between mortality rate and vitamin D status was observed throughout the globe (r= -0.177). In Asia, a medium direct correlation was observed for recovery rate (r= 0.317) and a significant reveres correlation for mortality rate (r= -0.700) with vitamin D status in such patients. In Europe, there were no correlations for both recovery (r= 0.040) and mortality rate (r= -0.035). In Middle East, the recovery rate (r= 0.267) and mortality rate (r= -0.217) showed a medium correlation. In North and Sought America, surprisingly, both recovery and mortality rate demonstrated a direct correlation respectively (r= 1.000, r=0.500). In Oceania, unexpectedly, recovery (r= -1.000) and mortality (r= -1.000) rates were in considerable reverse correlation with vitamin D levels. Conclusion: In this systematic review and meta-analysis with an ecological approach, we found a high percentage of COVID-19 patients who suffer from vitamin D deficiency or insufficiency. Much more important, our ecological investigation resulted in substantial direct and reverse correlations between recovery and mortality rates of COVID-19 patients with vitamin D status in different countries. Considering latitudes, a small reverse correlation between vitamin D status and mortality rate was found globally. It seems that populations with lower levels of vitamin D might be more susceptible to the novel coronavirus infection. Nevertheless, due to multiple limitations, if this study does not allow to quantify a value of the Vitamin D with full confidence, it allows at least to know what the Vitamin D might be and that it would be prudent to invest in this direction through comprehensive large randomized clinical trials.

The Role of Vitamin D in The Age of COVID-19: A Systematic Review and Meta-Analysis Along with an Ecological Approach

Phototherapy and vitamin D: the importance in COVID-19 era.

Synergistic effect of Vitamin D and Remdesivir can fight COVID-19.

Reply to Jakovac: About COVID-19 and vitamin D

Phototherapy and vitamin D: the importance in COVID-19 era

Vitamin D is produced in the skin under the influence of UVB-light from the sun or obtained via the diet by eating fatty fish, enriched dairy products or supplements. Vitamin D is known to support a healthy bone and severe deficiency may lead to osteomalacia or the rickets, which still occur in poor areas of the world. In addition, vitamin D support key functions in many organs, including the brain, muscle and the immune systems (Holick, 2007). In fact, the vitamin D receptor (VDR) is expressed in most cell types and may activate somewhere between 200-500 genes, many related to the immune system.

The link between Vitamin D and Covid-19: distinguishing facts from fiction.

Importance: Vitamin D treatment has been found to decrease incidence of viral respiratory tract infection, especially in vitamin D deficiency. It is unknown whether COVID-19 incidence is associated with vitamin D deficiency and treatment. Objective: To examine whether vitamin D deficiency and treatment are associated with testing positive for COVID-19. Design: Retrospective cohort study Setting: University of Chicago Medicine Participants: Patients tested for COVID-19 from 3/3/2020-4/10/2020. Vitamin D deficiency was defined by the most recent 25-hydroxycholecalciferol <20ng/ml or 1,25-dihydroxycholecalciferol <18pg/ml within 1 year before COVID-19 testing. Treatment was defined by the most recent vitamin D type and dose, and treatment changes between the time of the most recent vitamin D level and time of COVID-19 testing. Vitamin D deficiency and treatment changes were combined to categorize vitamin D status at the time of COVID-19 testing as likely deficient(last-level-deficient/treatment-not-increased), likely sufficient(last-level-not-deficient/treatment-not-decreased), or uncertain deficiency(last-level-deficient/treatment-increased or last-level-not-deficient/treatment-decreased). Main Outcomes and Measures: The main outcome was testing positive for COVID-19. Multivariable analysis tested whether the most recent vitamin D level and treatment changes after that level were associated with testing positive for COVID-19 controlling for demographic and comorbidity indicators. Bivariate analyses of associations of treatment with vitamin D deficiency and COVID-19 were performed. Results: Among 4,314 patients tested for COVID-19, 499 had a vitamin D level in the year before testing. Vitamin D status at the time of COVID-19 testing was categorized as likely deficient for 127(25%) patients, likely sufficient for 291(58%) patients, and uncertain for 81(16%) patients. In multivariate analysis, testing positive for COVID-19 was associated with increasing age(RR(age<50)=1.05,p<0.021;RR(age[≥]50)=1.02,p<0.064)), non-white race(RR=2.54,p<0.01) and being likely vitamin D deficient (deficient/treatment-not-increased:RR=1.77,p<0.02) as compared to likely vitamin D sufficient(not-deficient/treatment-not-decreased), with predicted COVID-19 rates in the vitamin D deficient group of 21.6%(95%CI[14.0%-29.2%] ) versus 12.2%(95%CI[8.9%-15.4%]) in the vitamin D sufficient group. Vitamin D deficiency declined with increasing vitamin D dose, especially of vitamin D3. Vitamin D dose was not significantly associated with testing positive for COVID-19. Conclusions and Relevance: Vitamin D deficiency that is not sufficiently treated is associated with COVID-19 risk. Testing and treatment for vitamin D deficiency to address COVID-19 warrant aggressive pursuit and study.

Association of Vitamin D Deficiency and Treatment with COVID-19 Incidence

Optimisation of Vitamin D Status for Enhanced Immuno-protection Against Covid-19

While we are still learning more about COVID-19, caused by the novel SARS-CoV-2 virus, finding alternative and already available methods to reduce the risk and severity of the disease is paramount. One such option is vitamin D, in the form of vitamin D(3) (cholecalciferol) supplementation, due to its potential antiviral properties. It has become apparent that older individuals have a greater risk of developing severe COVID-19, and compared to younger adults, the elderly have lower levels of vitamin D due to a variety of biological and behavioral factors. Older adults are also more likely to be diagnosed with Parkinson’s disease (PD), with advanced age being the single greatest risk factor. In addition to its immune-system-modulating effects, it has been suggested that vitamin D supplementation plays a role in slowing PD progression and improving PD-related quality of life. We completed a review of the literature to determine the relationship between vitamin D, PD, and COVID-19. We concluded that the daily supplementation of 2000–5000 IU/day of vitamin D(3) in older adults with PD has the potential to slow the progression of PD while also potentially offering additional protection against COVID-19.

Potential Role of Vitamin D in the Elderly to Resist COVID-19 and to Slow Progression of Parkinson’s Disease

Covid-19: Public health agencies review whether vitamin D supplements could reduce risk

Does vitamin D status impact mortality from SARS-CoV-2 infection?

Early reports indicate an association between the severity of the COVID-19 infection and the widespread 25-hydroxy vitamin D deficiency known to exist in populations around the world. Vitamin D deficiency is extremely common among African American (AA) communities, where the COVID-19 infection rate is three-fold higher, and the mortality rate nearly six-fold higher, compared with rates in predominantly white communities. COVID-19 infection primarily affects the lungs and airways. Previous reports have linked 25-hydroxy vitamin D deficiency with subclinical interstitial lung disease. AA are at risk for lower cellular glutathione (GSH) levels, and GSH deficiency epigenetically impairs VD biosynthesis pathway genes. Compared with vitamin D alone, co-supplementation of vitamin D and L-cysteine (a GSH precursor) showed a better efficacy in improving levels of GSH and VD-regulatory genes at the cellular/tissue level, increasing 25(OH) vitamin D levels, and reducing inflammation biomarkers in the blood in mice studies. We propose that randomized clinical trials are needed to examine the potential of co-supplementation with anti-inflammatory antioxidants, vitamin D and L-cysteine in correcting the 25(OH)VD deficiency and preventing the 'cytokine storm,' one of the most severe consequences of infection with COVID-19, thereby preventing the adverse clinical effects of COVID-19 infection in the vulnerable AA population.

Can Vitamin D and L-Cysteine Co-Supplementation Reduce 25(OH)-Vitamin D Deficiency and the Mortality Associated with COVID-19 in African Americans?

BACKGROUND: SARS-CoV-2 coronavirus infection ranges from asymptomatic through to fatal COVID-19 characterised by a "cytokine storm" and lung failure. Vitamin D deficiency has been postulated as a determinant of severity. OBJECTIVES: To review the evidence relevant to vitamin D and COVID-19 METHODS: Narrative review RESULTS: Regression modelling shows that more northerly countries in the Northern Hemisphere are currently (May 2020) showing relatively high COVID-19 mortality, with an estimated 4.4% increase in mortality for each 1 degree latitude north of 28 degrees North (P=0.031) after adjustment for age of population. This supports a role for ultraviolet B acting via vitamin D synthesis. Factors associated with worse COVID-19 prognosis include old age, ethnicity, male sex, obesity, diabetes and hypertension and these also associate with deficiency of vitamin D or its response. Vitamin D deficiency is also linked to severity of childhood respiratory illness. Experimentally, vitamin D increases the ratio of angiotensin converting enzyme 2 (ACE2) to ACE, thus increasing angiotensin II hydrolysis and reducing subsequent inflammatory cytokine response to pathogens and lung injury. CONCLUSIONS: Substantial evidence supports a link between vitamin D deficiency and COVID-19 severity but it is all indirect. Community-based placebo-controlled trials of vitamin D supplementation may be difficult. Further evidence could come from study of COVID-19 outcomes in large cohorts with information on prescribing data for vitamin D supplementation or assay of serum unbound 25(OH) vitamin D levels. Meanwhile vitamin D supplementation should be strongly advised for people likely to be deficient.

Perspective: Vitamin D deficiency and COVID-19 severity - plausibly linked by latitude, ethnicity, impacts on cytokines, ACE2, and thrombosis (R1)

Hypovitaminosis D and COVID-19: Matter of Concern in India?

BACKGROUND AND AIMS: Data show that vitamin D deficiency may play a role in patients with diabetes mellitus and COVID-19 infection. In this article, we review evidence of vitamin D deficiency and COVID-19 infection in context of diabetes mellitus. METHODS: A literature search was carried out by using the key term ‘COVID 19’ combined with ‘Diabetes’, ‘Vitamin D’, ‘Extra skeletal effects’, ‘immunity’, ‘infection’, ‘India’ from Pub Med (National Library of Medicine, Bethesda, MD and Google Scholar from December 2019 to May 2020. A manual search of the references was also carried out. RESULTS: Vitamin D deficiency has been linked to increased morbidity and mortality in COVID -19 infections but convincing data on diabetic subgroup of patients in particular is still awaited. CONCLUSION: Robust studies are required to ascertain if Vitamin D supplementation could be beneficial in patients with diabetes and COVID-19.

Vitamin D deficiency in patients with diabetes and COVID- 19 infection

BACKGROUND AND AIMS: Data show that vitamin D deficiency may play a role in patients with diabetes mellitus and COVID-19 infection. In this article, we review evidence of vitamin D deficiency and COVID-19 infection in context of diabetes mellitus. METHODS: A literature search was carried out by using the key term 'COVID 19' combined with 'Diabetes', 'Vitamin D', 'Extra skeletal effects', 'immunity', 'infection', 'India' from Pub Med (National Library of Medicine, Bethesda, MD and Google Scholar from December 2019 to May 2020. A manual search of the references was also carried out. RESULTS: Vitamin D deficiency has been linked to increased morbidity and mortality in COVID -19 infections but convincing data on diabetic subgroup of patients in particular is still awaited. CONCLUSION: Robust studies are required to ascertain if Vitamin D supplementation could be beneficial in patients with diabetes and COVID-19.

The link between Vitamin D and Covid-19: distinguishing facts from fiction

Synergistic effect of vitamin D and remdesivir can fight COVID-19

Vitamin D, Covid-19 and Children.

BACKGROUND: SARS‐CoV‐2 coronavirus infection ranges from asymptomatic through to fatal COVID‐19 characterised by a “cytokine storm” and lung failure. Vitamin D deficiency has been postulated as a determinant of severity. OBJECTIVES: To review the evidence relevant to vitamin D and COVID‐19 METHODS: Narrative review RESULTS: Regression modelling shows that more northerly countries in the Northern Hemisphere are currently (May 2020) showing relatively high COVID‐19 mortality, with an estimated 4.4% increase in mortality for each 1 degree latitude north of 28 degrees North (P=0.031) after adjustment for age of population. This supports a role for ultraviolet B acting via vitamin D synthesis. Factors associated with worse COVID‐19 prognosis include old age, ethnicity, male sex, obesity, diabetes and hypertension and these also associate with deficiency of vitamin D or its response. Vitamin D deficiency is also linked to severity of childhood respiratory illness. Experimentally, vitamin D increases the ratio of angiotensin converting enzyme 2 (ACE2) to ACE, thus increasing angiotensin II hydrolysis and reducing subsequent inflammatory cytokine response to pathogens and lung injury. CONCLUSIONS: Substantial evidence supports a link between vitamin D deficiency and COVID‐19 severity but it is all indirect. Community‐based placebo‐controlled trials of vitamin D supplementation may be difficult. Further evidence could come from study of COVID‐19 outcomes in large cohorts with information on prescribing data for vitamin D supplementation or assay of serum unbound 25(OH) vitamin D levels. Meanwhile vitamin D supplementation should be strongly advised for people likely to be deficient.

Perspective: Vitamin D deficiency and COVID‐19 severity – plausibly linked by latitude, ethnicity, impacts on cytokines, ACE2, and thrombosis (R1)

Background Recent research has indicated that vitamin D may have immune supporting properties through modulation of both the adaptive and innate immune system through cytokines and regulation of cell signalling pathways We hypothesize that vitamin D status may influence the severity of responses to Covid-19 and that the prevalence of vitamin D deficiency in Europe will be closely aligned to Covid-19 mortality Methods We conducted a literature search on PubMed (no language restriction) of vitamin D status (for older adults) in countries/areas of Europe affected by Covid-19 infection Countries were selected by severity of infection (high and low) and were limited to national surveys or where not available, to geographic areas within the country affected by infection Covid-19 infection and mortality data was gathered from the World Health Organisation Results Counter-intuitively, lower latitude and typically ‘sunny’ countries such as Spain and Italy (particularly Northern Italy), had low mean concentrations of 25(OH)D and high rates of vitamin D deficiency These countries have also been experiencing the highest infection and death rates in Europe The northern latitude countries (Norway, Finland, Sweden) which receive less UVB sunlight than Southern Europe, actually had much higher mean 25(OH)D concentrations, low levels of deficiency and for Norway and Finland, lower infection and death rates The correlation between 25(OH)D concentration and mortality rate reached conventional significance (P=0 046) by Spearman's Rank Correlation Conclusions Optimising vitamin D status to recommendations by national and international public health agencies will certainly have benefits for bone health and potential benefits for Covid-19 There is a strong plausible biological hypothesis and evolving epidemiological data supporting a role for vitamin D in Covid-19

Vitamin D and inflammation: Potential implications for severity of Covid-19

COVID-19, the disease caused by SARS-CoV-2 (1), was declared a pandemic by the World Health Organization (WHO) in March 2020 (2). While awaiting a vaccine, several antivirals are being used to manage the disease with limited success (3, 4). To expand this arsenal, we screened 4 compound libraries: a United States Food and Drug Administration (FDA) approved drug library, an angiotensin converting enzyme-2 (ACE2) targeted compound library, a flavonoid compound library as well as a natural product library. Of the 121 compounds identified with activity against SARS-CoV-2, 7 were shortlisted for validation. We show for the first time that the active form of Vitamin D, calcitriol, exhibits significant potent activity against SARS-CoV-2. This finding paves the way for consideration of host-directed therapies for ring prophylaxis of contacts of SARS-CoV-2 patients.

Calcitriol, the active form of vitamin D, is a promising candidate for COVID-19 prophylaxis

Commentary: Myths and facts on vitamin D amidst the COVID-19 pandemic

We analyse global data for COVID-19 deaths and recoveries and show that outbreak severity displays a striking latitude relationship with a northern hemisphere bias. Transmission rates can be explained by seasonal weather conditions, but this does not account for observed variations in fatality rates. Many factors point to Vitamin D as a candidate explanation but historical controversy surrounding Vitamin D studies and the lack of a coherent framework for causal inference has hampered acceptance of this explanation despite a wealth of evidence in its favour. We analyse global COVID-19 data using Causal Inference, constructing two contrasting directed acyclic graph (DAG) models, one causal and one acausal, and set out clearly multiple predictions made by each model. We show that observed data strongly match predictions made by the causal model but largely contradict those of the acausal model. We explore historic evidence further supporting the causal model. We review biochemical mechanisms that may explain the various ways in which vitamin D acts. We detail the mechanisms by which the SARS-Cov-2 virus causes the disease and known pathways that involve Vitamin D and show how these both protect against viral infection, as well as ameliorating disease symptoms in COVID-19 and other respiratory diseases. We examine the factors that govern confidence in causal inference models and conclude that a high level of confidence in a causal beneficial role for Vitamin D is justified.

Evidence Supports a Causal Model for Vitamin D in COVID-19 Outcomes

Myths and Facts on Vitamin D Amidst the COVID-19 Pandemic()

Is Vitamin D One of the Key Elements in COVID-19 Days?

Vitamin D and Coronavirus

Background: SARS-CoV-2 virus causes a very wide range of COVID-19 disease severity in humans: from completely asymptomatic to fatal, and the reasons behind it are often not understood. There is some data that Vitamin D may have protective effect, so authors decided to analyze European country-wide data to determine if Vitamin D levels are associated with COVID-19 population death rate. Methods: To retrieve the Vitamin D levels data, authors analyzed the Vitamin D European population data compiled by 2019 ECTS Statement on Vitamin D Status published in the European Journal of Endocrinology. For the data set to used for analysis, only recently published data, that included general adult population of both genders ages 40-65 or wider, and must have included the prevalence of Vitamin D deficiency. Results: There were 10 countries data sets that fit the criteria and were analyzed. Severe Vitamin D deficiency was defined as 25(OH)D less than 25 nmol/L (10 ng/dL). Pearson correlation analysis between death rate per million from COVID-19 and prevalence of severe Vitamin D deficiency shows a strong correlation with r = 0.76, p = 0.01, indicating significant correlation. Correlation remained significant, even after adjusting for age structure of the population. Additionally, over time, correlation strengthened, and r coefficient asymptoticaly increased. Conclusions: Authors recommend universal screening for Vitamin D deficiency, and further investigation of Vitamin D supplementation in randomized control studies, which may lead to possible treatment or prevention of COVID-19.

Strong Correlation Between Prevalence of Severe Vitamin D Deficiency and Population Mortality Rate from COVID-19 in Europe

Vitamin D deficiency and the COVID-19 pandemic

The study reviews the evidence presented in a recent study linking vitamin D levels and Covid-19 infection and mortality. It was argued that correlation alone may not be useful in establishing a relationship between vitamin D levels and Covid-19 infections and mortality. Appropriate controls need to be included for improved understanding of the relationship. We proposed life expectancy as a potential control. Including this control in a regression model, we find that vitamin D levels are not a statistically significant predictor of Covid-19 infections or mortality. Life expectancy, on the other hand, was found to be statistically significant predictor of infections and mortality at country level.

Spurious Correlation? A review of the relationship between Vitamin D and Covid-19 infection and mortality

OBJECTIVES: Vitamin D deficiency (VDD) has been proposed to play a role in Coronavirus Disease 2019 (COVID-19) pathophysiology. We aim to evaluate our implementation of a local protocol for treatment of VDD among patients hospitalized for COVID-19; to assess the prevalence of VDD among COVID-19 inpatients, and examine potential associations with disease severity and fatality. DESIGN AND PARTICIPANTS: We conducted a retrospective interim audit of a local clinical care pathway for 134 inpatients with COVID-19. Prevalence of VDD, compliance with local treatment protocol and relationship of baseline serum 25(OH)D with markers of COVID-19 severity and fatality were analysed. RESULTS: 55.8% of eligible patients received Colecalciferol replacement, albeit not all according to the suggested protocol. Patients admitted to ITU were younger than those managed on medical wards (61.1 years ± 11.8 vs. 76.4 years ± 14.9, respectively, p<0.001), with greater prevalence of hypertension, higher baseline respiratory rate, National Early Warning Score-2 and C-Reactive protein level. While mean serum 25(OH)D levels were comparable (p=0.3), only 19% of ITU patients had 25(OH)D levels greater than 50 nmol/L vs. 39.1% of non-ITU patients (p=0.02). However, there was no association with fatality, potentially due to small sample size and prompt diagnosis and treatment of VDD. CONCLUSIONS: Higher prevalence of VDD was observed in patients requiring ITU admission compared to patients managed on medical wards. Larger prospective studies and/or clinical trials are needed to validate and extend our observations.

Low serum 25-hydroxyvitamin D (25[OH]D) levels in patients hospitalised with COVID-19 are associated with greater disease severity

Vitamin D deficiency, which impedes good immune function, is common during winter and spring in regions of high latitude. There is good evidence that vitamin D deficiency contributes to the seasonal increase of virus infections of the respiratory tract, from the common cold to influenza, and now possibly also COVID-19. This communication explores key factors that make it more likely, particularly in combination, that individuals are vitamin D deficient. These factors include old age, obesity, dark skin tone and common genetic variants that impede vitamin D status. Precision nutrition is an approach that aims to consider known personal risk factors and health circumstances to provide more effective nutrition guidance in health and disease. In regard to avoiding vitamin D deficiency, people with excess body fat, a dark skin tone or older age usually need to use a moderately dosed daily vitamin D supplement, particularly those living in a high-latitude region, getting little ultraviolet B exposure due to air pollution or staying mostly indoors. Carriers of the GC (group-specific component) rs4588 AA genotype also are more likely to become deficient. Very high-dosed supplements with more than 4000 IU vitamin D are rarely needed or justified. A state-by-state Mendelian randomisation analysis of excess COVID-19 mortality of African-Americans in the USA shows a greater disparity in northern states than in southern states. It is conceivable that vitamin D adequacy denies the virus easy footholds and thereby slows spreading of the contagion. This finding should drive home the message that vitamin D supplementation is particularly important for individuals with dark skin tones. Vitamin D deficiency, even for a few months during the winter and spring season, must be rigorously remedied because of its many adverse health impacts that include decreased life expectancy and increased mortality. Slowing the spread of COVID-19 would be an added bonus.

Avoidance of vitamin D deficiency to slow the COVID-19 pandemic

OBJECTIVES: Vitamin D deficiency (VDD) has been proposed to play a role in Coronavirus Disease 2019 (COVID‐19) pathophysiology. We aim to evaluate our implementation of a local protocol for treatment of VDD among patients hospitalized for COVID‐19; to assess the prevalence of VDD among COVID‐19 inpatients, and examine potential associations with disease severity and fatality. DESIGN AND PARTICIPANTS: We conducted a retrospective interim audit of a local clinical care pathway for 134 inpatients with COVID‐19. Prevalence of VDD, compliance with local treatment protocol and relationship of baseline serum 25(OH)D with markers of COVID‐19 severity and fatality were analysed. RESULTS: 55.8% of eligible patients received Colecalciferol replacement, albeit not all according to the suggested protocol. Patients admitted to ITU were younger than those managed on medical wards (61.1 years ± 11.8 vs. 76.4 years ± 14.9, respectively, p<0.001), with greater prevalence of hypertension, higher baseline respiratory rate, National Early Warning Score‐2 and C‐Reactive protein level. While mean serum 25(OH)D levels were comparable (p=0.3), only 19% of ITU patients had 25(OH)D levels greater than 50 nmol/L vs. 39.1% of non‐ITU patients (p=0.02). However, there was no association with fatality, potentially due to small sample size and prompt diagnosis and treatment of VDD. CONCLUSIONS: Higher prevalence of VDD was observed in patients requiring ITU admission compared to patients managed on medical wards. Larger prospective studies and/or clinical trials are needed to validate and extend our observations.

Low serum 25‐hydroxyvitamin D (25[OH]D) levels in patients hospitalised with COVID‐19 are associated with greater disease severity

Patients with respiratory diseases such as cystic fibrosis, chronic obstructive pulmonary disease, or asthma often experience an acute worsening of respiratory symptoms, termed exacerbations. Although the course of exacerbations is disease specific, they are mostly triggered by a respiratory infection. Exacerbations often require hospitalization and are an important cause of mortality. Treatments of exacerbations aim to minimize the negative impact and to prevent subsequent events. Despite many existing therapy options, many patients do not benefit from therapy and suffer from recurrent events. Vitamin D deficiency is a worldwide problem and is extremely prevalent in these patients. Vitamin D, known for its calcemic effects, also has immunomodulatory and anti-infectious actions and can therefore be a possible agent to treat or prevent exacerbations. This review will focus on vitamin D as a potential candidate to treat or prevent exacerbations in CF, COPD, and asthma.

Targeting Vitamin D Deficiency to Limit Exacerbations in Respiratory Diseases: Utopia or Strategy With Potential?

LINKED CONTENT This article is linked to Sands et al papers. To view these articles, visit https://doi.org/10.1111/apt.15555 and https://doi.org/10.1111/apt.15716.

Letter: Covid‐19, and vitamin D. Authors' reply

Purpose Vitamin D has been proposed as a potential causal factor in COVID-19 risk. We aimed to establish whether blood 25-hydroxyvitamin D (25(OH)D) concentration was associated with COVID-19 mortality, and inpatient confirmed COVID-19 infection, in UK Biobank participants. Methods UK Biobank recruited 502,624 participants aged 37-73 years between 2006 and 2010. Baseline exposure data, including 25(OH)D concentration, were linked to COVID-19 mortality. Univariable and multivariable Cox proportional hazards regression analyses were performed for the association between 25(OH)D and COVID-19 death, and poisson regression analyses for the association between 25(OH)D and severe COVID-19 infection. Results Complete data were available for 341,484 UK Biobank participants, of which 656 had inpatient confirmed COVID-19 infection and 203 died of COVID-19 infection. Vitamin D was associated with severe COVID-19 infection and mortality univariably (mortality HR=0.99; 95% CI 0.98-0.998; p=0.016), but not after adjustment for confounders (mortality HR=0.998; 95% CI=0.99-1.01; p=0.696). Conclusions Our findings do not support a potential link between vitamin D concentrations and risk of severe COVID-19 infection and mortality. Recommendations for vitamin D supplementation to lessen COVID-19 risks may provide false reassurance.

Short Communication: Vitamin D and COVID-19 infection and mortality in UK Biobank

Covid-19, Cocooning and Vitamin D Intake Requirements.

Importance: Vitamin D deficiency increases the incidence of respiratory virus infections. More than 1 billion people worldwide are vitamin D deficient. If vitamin D deficiency is associated to incidence or severity of SARS-CoV-2 infection, a global call could be made for vitamin D supplementation to mitigate the pandemic. Objective: to determine if lower serum 25-hydroxyvitamin D (25(OH)D) levels are correlated to the risk for COVID-19 and its severity as measured by CT Design: single-center observational study Setting: AZ Delta general hospital Participants: 186 consecutive patients with PCR-confirmed SARS-CoV-2 infection hospitalized for COVID-19 from March 1, 2020 to April 7, 2020 Main outcome and measures: comparative analysis of 25(OH)D levels in patients hospitalized for COVID-19 at various radiological stages and a season/age/sex-matched diseased control population Results: we report on 186 SARS-CoV-2 infected patients requiring hospitalization for severe COVID-19: 109 males (median age 68 years, IQR 53-79 years) and 77 females (median age 71 years, IQR 65-74 years). At admission patients were screened by CT to determine temporal changes of COVID-19 lung disease and classified as stage 1 (ground glass opacities), 2 (crazy paving pattern) and 3 (consolidation). At intake, 25(OH)D levels were measured and compared to a season-matched population of 2717 diseased controls, consisting of 999 males (median age 69 years, IQR 53-81 years) and 1718 females (median age 68 years, IQR 43-83 years). Male and female COVID-19 patients combined showed lower median 25(OH)D than controls (18.6 ng/mL, IQR 12.6-25.3, versus 21.5 ng/mL, IQR 13.9-30.8; P=0.0016) and a higher fraction of vitamin D deficiency (58.6% versus 45.2%, P=0.0005). A strong sexual dimorphism was found: female patients had comparable vitamin D status as control females. Male COVID-19 patients, however, showed markedly higher percentage of vitamin D deficiency than controls (67.0% versus 49.2%, P=0.0006) and this effect was more pronounced with advanced radiological stage ranging from 55.2% in stage 1 to 74% in stage 3. Conclusions and relevance: vitamin D deficiency is a possible risk factor for severe SARS-CoV-2 infection in males. Vitamin D supplementation might be an inexpensive, accessible and safe mitigation for the SARS-CoV-2 pandemic.

Vitamin D deficiency as risk factor for severe COVID-19: a convergence of two pandemics

Viramina D e coronavirus: un nuovo campo di impiego?/ [Vitamin D and coronavirus: a new field of use?]

Vitamin D, Covid-19 and Children

LINKED CONTENT This article is linked to Tian et al and Tian and Rong papers. To view these articles, visit https://doi.org/10.1111/apt.15731 and https://doi.org/10.1111/apt.15764.

Letter: Covid‐19, and vitamin D

There is anecdotal evidence that tocilizumab, an immunosuppressant drug, may be a potential therapeutic option for patients with severe manifestations of coronavirus disease 2019 (COVID-19). Like tocilizumab, Vitamin D appears to modulate the activity of an interleukin (IL-6), which may explain the seasonal variation in prevalence of influenza. While most cases of COVID-19 have, thus far, occurred in the Northern Hemisphere winter, limiting the ability to assess seasonal variation, there remains substantial variation in the severity of this condition that has yet to be explained. A retrospective comparison of Vitamin D levels in previously obtained blood samples between survivors and confirmed fatalities could establish a rationale for implementation of widespread Vitamin D supplementation. This would be far cheaper and simpler than tocilizumab as a therapeutic option to trial.

Vitamin D: A simpler alternative to tocilizumab for trial in COVID-19?

Vitamin D Deficiency and ARDS after SARS-CoV-2 Infection.

Can early and high intravenous dose of vitamin C prevent and treat coronavirus disease 2019 (COVID-19)?

Vitamin d deficiency and ards after sars-cov-2 infection

The current SARS-CoV-2 pandemic has mandated significant isolation measures. Streets in affected countries are mostly empty, and many individuals spend several consecutive days at home to reduce the risk of infection. While determinant for pandemic control, home reclusion may have a significant toll on the health of individuals.

SARS‐CoV‐2 pandemic and Vitamin D deficiency—A double trouble

The recent editorial by Rhodes et al considered latitude and mentioned one mechanism that vitamin D is important in regulating and suppressing the inflammatory response of cytokines of respiratory epithelial cells and macrophages to various pathogens, including respiratory viruses and preventing cytokine storm and the subsequent acute respiratory distress syndrome (RDS) (1).

Letter: low population mortality from COVID‐19 in countries south of latitude 35 degrees North supports vitamin D as a factor determining severity

Association between low vitamin D and COVID-19: don't forget the vitamin D binding protein.

Background: Vitamin D deficiency has been shown to be independently associated with increased risk of viral acute respiratory infection (ARI) in a number of observational studies, and meta-analysis of clinical trials of vitamin D supplementation for prevention of ARI has demonstrated protective effects. Several cellular studies have investigated the effects of vitamin D metabolites on immune responses to respiratory viruses, but syntheses of these reports are lacking. Scope: In this article, we review the literature reporting results of in vitro experiments investigating immunomodulatory actions of vitamin D metabolites in human respiratory epithelial cells infected with respiratory viruses. Key findings: Vitamin D metabolites do not consistently influence replication or clearance of rhinovirus, respiratory syncytial virus (RSV) or influenza A virus in human respiratory epithelial cell culture, although they do modulate expression and secretion of type 1 interferon, chemokines including CXCL8 and CXCL10 and pro-inflammatory cytokines, such as TNF and IL-6. Future research: More studies are needed to clarify the effects of vitamin D metabolites on respiratory virus-induced expression of cell surface markers mediating viral entry and bacterial adhesion to respiratory epithelial cells.

Modulation of the Immune Response to Respiratory Viruses by Vitamin D

Low serum 25-hydroxyvitamin D (25D) levels in patients hospitalised with COVID-19 are associated with greater disease severity: results of a local audit of practice.

Association between low vitamin D and COVID-19: don't forget the vitamin D binding protein

The novel coronavirus disease 2019 (COVID-19) is rapidly expanding and causing many deaths all over the world with the World Health Organization (WHO) declaring a pandemic in March 2020. Current therapeutic options are limited and there is no registered and/or definite treatment or vaccine for this disease or the causative infection, severe acute respiratory coronavirus 2 syndrome (SARS-CoV-2). Angiotensin-converting enzyme 2 (ACE2), a part of the renin-angiotensin system (RAS), serves as the major entry point into cells for SARS-CoV-2 which attaches to human ACE2, thereby reducing the expression of ACE2 and causing lung injury and pneumonia. Vitamin D, a fat-soluble-vitamin, is a negative endocrine RAS modulator and inhibits renin expression and generation. It can induce ACE2/Ang-(1-7)/MasR axis activity and inhibits renin and the ACE/Ang II/AT1R axis, thereby increasing expression and concentration of ACE2, MasR and Ang-(1-7) and having a potential protective role against acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Therefore, targeting the unbalanced RAS and ACE2 down-regulation with vitamin D in SARS-CoV-2 infection is a potential therapeutic approach to combat COVID-19 and induced ARDS.

A brief review of interplay between vitamin D and angiotensin-converting enzyme 2: Implications for a potential treatment for COVID-19

A number of clues point to a possible role of vitamin D in fighting COVID-19: a reduction in case growth speed with solar zenith angle, higher fatality rate in black people, lower fatality rate in populations that spend more time outdoors. Yet a direct demonstration that vitamin D deficiency is associated with COVID-19 fatalities has remained elusive. We show here in a comparison of 32 countries that countries with high prevalence of vitamin D deficiency among elderly females show a confirmed case fatality rate twice as high as those with low prevalence. We then show that this effect cannot be explained by differences in life expectancy between countries. A mechanistic role for vitamin D in the severity of COVID-19 is proposed.

Double COVID-19 Confirmed Case Fatality Rate in Countries with High Elderly Female Vitamin D Deficiency Prevalence

Vitamin D deficiency and co-morbidities in COVID-19 patients – A fatal relationship?

Aim: To evaluate associations of plasma 25(OH)D status with the likelihood of coronavirus disease (COVID-19) infection and hospitalization. Methods: The study population included the 14,000 members of Leumit Health Services who were tested for COVID-19 infection from February 1st to April 30th, 2020, and who had at least one previous blood test for plasma 25(OH)D level. "Suboptimal" or "low" plasma 25(OH)D level was defined as plasma 25-hydroxyvitamin D, or 25(OH)D, concentration below 30 ng/mL. Results: Of 7,807 individuals, 782 (10.1%) were COVID-19-positive, and 7,025 (89.9%) COVID-19-negative. The mean plasma vitamin D level was significantly lower among those who tested positive than negative for COVID-19 [19.00 ng/mL (95% confidence interval [CI] 18.41-19.59) vs. 20.55 (95% CI 20.32-20.78)]. Univariate analysis demonstrated an association between low plasma 25(OH)D level and increased likelihood of COVID-19 infection [crude odds ratio (OR) of 1.58 (95% CI 1.24-2.01, p<0.001)], and of hospitalization due to the SARS-CoV-2 virus [crude OR of 2.09 (95% CI 1.01-4.30, p<0.05)]. In multivariate analyses that controlled for demographic variables and psychiatric and somatic disorders, the adjusted OR of COVID-19 infection [1.45 (95% CI 1.08-1.95, p<0.001)], and of hospitalization due to the SARS-CoV-2 virus [1.95 (95% CI 0.98-4.845, p=0.061)] were preserved. In the multivariate analyses, age over 50 years, male gender and low-medium socioeconomic status were also positively associated with the risk of COVID-19 infection; age over 50 years was positively associated with the likelihood of hospitalization due to COVID-19.

Low plasma 25(OH) vitamin D3 level is associated with increased risk of COVID-19 infection: an Israeli population-based study