Perspective: Vitamin D supplementation prevents rickets and acute respiratory infections when given as daily maintenance but not as intermittent bolus: implications for COVID-19

Nutritional and metabolic modulation of inflammation in critically ill patients: a narrative review of rationale, evidence and grey areas

BACKGROUND

Inflammation is the hallmark of critical illness and triggers the neuro-endocrine stress response and an oxidative stress. Acute inflammation is initially essential for patient's survival. However, ongoing or exaggerated inflammation, due to persistent organ dysfunction, immune dysfunction or poor inflammation resolution, is associated to subsequent hypermetabolism and hypercatabolism that severely impact short and long-term functional status, autonomy, as well as health-related costs. Modulation of inflammation is thus tempting, with the goal to improve the short- and long-term outcomes of critically ill patients.

FINDINGS

Inflammation can be modulated by nutritional strategies (including the timing of enteral nutrition initiation, the provision of some specific macronutrients or micronutrients, the use of probiotics) and metabolic treatments. The most interesting strategies seem to be n-3 polyunsaturated fatty acids, vitamin D, antioxidant micronutrients and propranolol, given their safety, their accessibility for clinical use, and their benefits in clinical studies in the specific context of critical care. However, the optimal doses, timing and route of administration are still unknown for most of them. Furthermore, their use in the recovery phase is not well studied and defined.

CONCLUSION

The rationale to use strategies of inflammation modulation is obvious, based on critical illness pathophysiology and based on the increasingly described effects of some nutritional and pharmacological strategies. Regretfully, there isn't always substantial proof from clinical research regarding the positive impacts directly brought about by inflammation modulation. Some arguments come from studies performed in severe burn patients, but such results should be transposed to non-burn patients with caution. Further studies are needed to explore how the modulation of inflammation can improve the long-term outcomes after a critical illness.

Efficacy and safety of enteral supplementation with high-dose vitamin D in critically ill patients with vitamin D deficiency

BACKGROUND

Vitamin D deficiency is associated with mortality and morbidity in critically ill patients. This study investigated the safety and effectiveness of enteral high-dose vitamin D supplementation in intensive care unit (ICU) patients in Asia.

METHODS

This was a multicenter, prospective, randomized-controlled study. Eligible participants with vitamin D deficiency were randomly assigned to the control or vitamin D supplementation group. In the vitamin D supplementation group, the patients received 569,600 IU vitamin D. The primary outcome was the serum 25(OH)D level on day 7.

RESULTS

41 and 20 patients were included in the vitamin D supplementation and control groups, respectively. On day 7, the serum 25(OH)D level was significantly higher in the vitamin D supplementation group compared to the control group (28.5 [IQR: 20.2-52.6] ng/mL and 13.9 [IQR: 11.6-18.8] ng/mL, p < 0.001). Only 41.5% of the patients achieved serum 25(OH)D levels higher than 30 ng/mL in the supplementation group. This increased level was sustained in the supplementation group on both day 14 and day 28. There were no significant adverse effects noted in the supplementation group. Patients who reached a serum 25(OH)D level of >30 ng/mL on day 7 had a significantly lower 30-day mortality rate than did those who did not (5.9% vs 37.5%, p < 0.05).

CONCLUSIONS

In our study, less than half of the patients reached adequate vitamin D levels after the enteral administration of high-dose vitamin D. A reduction in 30-day mortality was noted in the patients who achieved adequate vitamin D levels. TRIAL REGISTRATION CLINICALTRIALS.

GOV ID

NCT04292873, Registered, March 1, 2020.

[Prevention and treatment of COVID-19 based on post-genomic pharmacological analysis: Systematic computer analysis of 290,000 scientific articles on COVID-19]

The COVID-19 pandemic has highlighted pressing challenges in biomedical research methodology. It has become obvious that the rapid and effective development of treatments for "new" viral infections is impossible without the coordination of interdisciplinary research and in-depth analysis of data obtained within the framework of the post-genomic paradigm. Presents the results of a systematic computer analysis of 290,000 scientific articles on COVID-19, with an emphasis on the results of post-genomic studies of SARS-CoV-2. The futility of the overly simplified approach, which considers only one "most important receptor protein", only one "key virus gene", etc., is shown. It is shown how post-genomic technologies will make it possible to find informative biomarkers of severe coronavirus infection, including those based on complex immune disorders associated with COVID-19.

High-dose vitamin D supplementation in patients with COVID-19: A meta-analysis of randomized controlled trials

The efficacy of administering high doses of vitamin D to patients diagnosed with COVID-19 remains uncertain. We conducted a comprehensive search across multiple databases (PubMed, EMBASE, Cochrane Library, and ISI Web of Science) from inception until August 2022, with no limitations on language, to locate randomized controlled trials (RCTs) that investigated the impact of high-dose vitamin D supplementation (defined as a single dose of ≥100,000 IU or daily dose of ≥10,000 IU reaching a total dose of ≥100,000 IU) on COVID-19 patients. Risk ratios (RR) with 95% confidence intervals (CI) and weighted mean differences (WMD) with 95% CI were calculated. Our meta-analysis included 5 RCTs with a total of 834 patients. High-dose vitamin D supplementation did not show any significant benefits for mortality (I 2 = 0.0%, p = .670; RR 1.092, 95% CI 0.685-1.742, p = .711) or intensive care unit (ICU) admission (I 2 = 0.0%, p = .519; RR 0.707, 95% CI 0.454-1.102, p = .126) in COVID-19 patients compared to the control group. However, it was found to be safe and well-tolerated (I 2 = 0.0%, p = .887; RR 1.218, 95% CI 0.930-1.594, p = .151). Subgroup analysis also showed no benefits in overall mortality, including for patients with vitamin D deficiency (I 2 = 0.0%, p = .452; RR 2.441, 95% CI 0.448-13.312, p = .303) or compared to the placebo (I 2 = 0.0%, p = .673; RR 1.666, 95% CI 0.711-3.902, p = .240). Our research indicates that there is no evidence to support the efficacy of high-dose vitamin D supplementation in improving clinical outcomes among individuals with COVID-19, in line with previous studies focused on contexts including rickets. Considering the limitations of the study, additional research may be required.

ESPEN practical short micronutrient guideline

BACKGROUND

Trace elements and vitamins, named together micronutrients (MNs), are essential for human metabolism. The importance of MNs in common pathologies is recognized by recent research, with deficiencies significantly impacting the outcome.

OBJECTIVE

This short version of the guideline aims to provide practical recommendations for clinical practice.

METHODS

An extensive search of the literature was conducted in the databases Medline, PubMed, Cochrane, Google Scholar, and CINAHL for the initial guideline. The search focused on physiological data, historical evidence (for papers published before PubMed release in 1996), and observational and/or randomized trials. For each MN, the main functions, optimal analytical methods, impact of inflammation, potential toxicity, and provision during enteral or parenteral nutrition were addressed. The SOP wording was applied for strength of recommendations.

RESULTS

The limited number of interventional trials prevented meta-analysis and led to a low level of evidence for most recommendations. The recommendations underwent a consensus process, which resulted in a percentage of agreement (%): strong consensus required of >90 % of votes. Altogether the guideline proposes 3 general recommendations and specific recommendations for the 26 MNs. Monitoring and management strategies are proposed.

CONCLUSION

This short version of the MN guideline should facilitate handling of the MNs in at-risk diseases, whilst offering practical advice on MN provision and monitoring during nutritional support.

The science of micronutrients in clinical practice - Report on the ESPEN symposium

BACKGROUND & AIMS

The European Society for Clinical Nutrition and Metabolism published its first clinical guidelines for use of micronutrients (MNs) in 2022. A two-day web symposium was organized in November 2022 discussing how to apply the guidelines in clinical practice. The present paper reports the main findings of this symposium.

METHODS

Current evidence was discussed, the first day being devoted to clarifying the biology underlying the guidelines, especially regarding the definition of deficiency, the impact of inflammation, and the roles in antioxidant defences and immunity. The second day focused on clinical situations with high prevalence of MN depletion and deficiency.

RESULTS

The importance of the determination of MN status in patients at risk and diagnosis of deficiencies is still insufficiently perceived, considering the essential role of MNs in immune and antioxidant defences. Epidemiological data show that deficiencies of several MNs (iron, iodine, vitamin D) are a global problem that affects human health and well-being including immune responses such as to vaccination. Clinical conditions frequently associated with MN deficiencies were discussed including cancer, obesity with impact of bariatric surgery, diseases of the gastrointestinal tract, critical illness, and aging. In all these conditions, MN deficiency is associated with worsening of outcomes. The recurrent problem of shortage of MN products, but also lack of individual MN-products is a worldwide problem.

CONCLUSION

Despite important progress in epidemiology and clinical nutrition, numerous gaps in practice persist. MN depletion and deficiency are frequently insufficiently searched for in clinical conditions, leading to inadequate treatment. The symposium concluded that more research and continued education are required to improve patient outcome.

The role of vitamin D in the prevention and treatment of SARS-CoV-2 infection: A meta-analysis of randomized controlled trials

BACKGROUND

Vitamin D (VitD) has been shown to be important for the immune response of the respiratory system, but the preventive and therapeutic effects of vitamin D supplementation on SARS-CoV-2 infection are controversial. This study aimed to determine the role of vitamin D supplementation in the prevention and treatment of SARS-CoV-2 infection through a meta-analysis of randomized controlled trials.

METHODS

The databases of PubMed, Cochrane Library, Embase, Web of Science and Google Scholar were searched systematically from inception to April 17,2023 to identify trials involving a randomized comparison of vitamin D supplementation versus non-vitamin D supplementation for SARS-CoV-2 infection prevention or treatment.

RESULTS

We retrieved 25 eligible trials, including 8128 participants. Four trials compared the preventive effects of vitamin D supplementation on SARS-CoV-2 infection, and the results (RR 0.31; 95%CI 0.07 to 1.32) were inconclusive. Regarding the treatment of SARS-CoV-2 infection with vitamin D supplementation, it was found that vitamin D supplementation could significantly reduce the rates of ICU admission (RR 0.63; 95%CI 0.44 to 0.89) and mechanical ventilation (RR 0.58; 95%CI 0.39 to 0.84), but had no statistically significant effect on mortality. However, in subgroup analyses based on the patients' specific conditions, vitamin D supplementation significantly reduced the mortality in patients with vitamin D deficiency (RR 0.76; 95%CI 0.58 to 0.98).

CONCLUSION

Vitamin D supplementation may have some beneficial impact on the severity of illness caused by SARS-CoV-2, particularly in VitD deficient patients, but further studies are still needed.

Vitamin D: immune function, inflammation, infections and auto-immunity

Vitamin D plays an active role beyond mineral metabolism and skeletal health, including regulation of the immune system. Vitamin D deficiency is widely prevalent, and observational studies link low vitamin D status to a risk of infections and auto-immune disorders. Reports indicate an inverse relationship between vitamin D status and such conditions. This review details vitamin D signalling interactions with the immune system and provides experimental and clinical evidence evaluating vitamin D status, vitamin D supplementation and host susceptibility to infections, inflammation and auto-immunity. The published literature including related reviews, systematic reviews, meta-analyses, randomised controlled trials (RCTs), observational studies and basic science reports have been synthesised. Meta-analyses of observational studies have demonstrated a link between low vitamin D status and risk of acute respiratory infections, COVID-19 disorders, multiple sclerosis, type 1 diabetes (T1DM), inflammatory bowel disease (IBD), systemic lupus erythematosus and other auto-immune disorders. Observational studies suggest that vitamin D supplementation may protect against several infectious and auto-immune conditions. Meta-analyses of RCTs had mixed results, demonstrating a small protective role for vitamin D supplementation against acute respiratory infections, especially in those with vitamin D deficiency and children, and providing modest benefits for the management of T1DM and IBD. Vitamin D status is inversely associated with the incidence of several infectious and auto-immune conditions. Supplementation is recommended for those with vitamin D deficiency or at high risk of deficiency, and it might provide additional benefit in acute respiratory infections and certain auto-immune conditions.

The effect of 1-hydroxy-vitamin D treatment in hospitalized patients with COVID-19: A retrospective study

BACKGROUND & AIMS

The efficacy of vitamin D supplementation in coronavirus disease 2019 (COVID-19) remains unclear. This study aimed to evaluate the effect of 1-hydroxy-vitamin D on the prevention of severe disease and mortality in patients hospitalized for COVID-19.

METHODS

This retrospective study included 312 patients with COVID-19 who were admitted to our hospital between April 2021 and October 2021 (primarily the Delta variant) and between July 2022 and September 2022 (primarily Omicron variant). Serum 25-hydroxyvitamin D (25(OH)D) levels were measured at the time of admission and 1-hydroxy-vitamin D was prescribed by the treating physicians. The patients were divided into two groups: those administered 1-hydroxy-vitamin D (Vit D group) and those who were not (control group). The composite primary endpoint was the need for additional respiratory support, including high-flow oxygen therapy or invasive mechanical ventilation, and in-hospital mortality rate.

RESULTS

Of 312 patients, 122 (39%) received 1-hydroxy-vitamin D treatment. Although the median age was not significantly higher in the Vit D group than in the control group (66 vs. 58 years old, P = 0.06) and there was no significant difference in the proportion of vitamin D deficiency (defined as serum 25(OH)D level less than 20 ng/mL, 77% vs. 65%, P = 0.07), patients in the control group had a more severe baseline profile compared to the Vit D group according to the Japanese disease severity definition for COVID-19 (P = 0.01). The proportion of those requiring more respiratory support and in-hospital mortality was significantly lower in the Vit D group than in the control group (6% vs. 14%, P = 0.01 log-rank test). After propensity score matching, a statistically significant difference in the primary endpoint was observed (P = 0.03 log-rank test).

CONCLUSIONS

1-hydroxy-vitamin treatment may improve outcomes in hospitalized patients with COVID-19, reducing composite outcomes including the need for additional respiratory support and in-hospital mortality.

Randomised controlled trial of perinatal vitamin D supplementation to prevent early-onset acute respiratory infections among Australian First Nations children: the 'D-Kids' study protocol

INTRODUCTION

Globally, acute respiratory infections (ARIs) are a leading cause of childhood morbidity and mortality. While ARI-related mortality is low in Australia, First Nations infants are hospitalised with ARIs up to nine times more often than their non-First Nations counterparts. The gap is widest in the Northern Territory (NT) where rates of both acute and chronic respiratory infection are among the highest reported in the world. Vitamin D deficiency is common among NT First Nations neonates and associated with an increased risk of ARI hospitalisation. We hypothesise that perinatal vitamin D supplementation will reduce the risk of ARI in the first year of life.

METHODS AND ANALYSIS

'D-Kids' is a parallel (1:1), double-blind (allocation concealed), randomised placebo-controlled trial conducted among NT First Nations mother-infant pairs. Pregnant women and their babies (n=314) receive either vitamin D or placebo. Women receive 14 000 IU/week or placebo from 28 to 34 weeks gestation until birth and babies receive 4200 IU/week or placebo from birth until age 4 months. The primary outcome is the incidence of ARI episodes receiving medical attention in the first year of life. Secondary outcomes include circulating vitamin D level and nasal pathogen prevalence. Tertiary outcomes include infant immune cell phenotypes and challenge responses. Blood, nasal swabs, breast milk and saliva are collected longitudinally across four study visits: enrolment, birth, infant age 4 and 12 months. The sample size provides 90% power to detect a 27.5% relative reduction in new ARI episodes between groups.

ETHICS AND DISSEMINATION

This trial is approved by the NT Human Research Ethics Committee (2018-3160). Study outcomes will be disseminated to participant families, communities, local policy-makers, the broader research and clinical community via written and oral reports, education workshops, peer-reviewed journals, national and international conferences.

TRIAL REGISTRATION NUMBER

ACTRN12618001174279.

SARS-CoV-2 Systemic Effects: New Clues

To date, much discussion has been had on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lung infection associated with COVID-19 onset, of which the major manifestation is characterized by a "cytokine storm" [...].

Drugs in primary care that may alter COVID-19 risk and severity

ABSTRACT

This article describes drugs used in primary care that could alter patients' risk for and severity of COVID-19. The risks and benefits of each drug class were differentiated according to the strength of evidence from 58 selected randomized controlled trials, systematic reviews, and meta-analyses. Most of the studies reported on drugs affecting the renin-angiotensin-aldosterone system. Other classes included opioids, acid suppressants, nonsteroidal anti-inflammatory drugs, corticosteroids, vitamins, biguanides, and statins. Current evidence has not fully differentiated drugs that may increase risk versus benefits in COVID-19 infection. Further studies are needed in this area.

Evidence That Increasing Serum 25(OH)D Concentrations to 30 ng/mL in the Kingdom of Saudi Arabia and the United Arab Emirates Could Greatly Improve Health Outcomes

Accumulating evidence supports the potential protective effects of vitamin D against chronic diseases such as Alzheimer’s disease, autoimmune diseases, cancers, cardiovascular disease (ischaemic heart disease and stroke), type 2 diabetes, hypertension, chronic kidney disease, stroke, and infectious diseases such as acute respiratory tract diseases, COVID-19, influenza, and pneumonia, as well as adverse pregnancy outcomes. The respective evidence is based on ecological and observational studies, randomized controlled trials, mechanistic studies, and Mendelian randomization studies. However, randomized controlled trials on vitamin D supplementation have largely failed to show benefits, probably due to poor design and analysis. In this work, we aim to use the best available evidence on the potential beneficial effects of vitamin D to estimate the expected reduction in incidence and mortality rates of vitamin D-related diseases in the Kingdom of Saudi Arabia and the United Arab Emirates if minimum serum 25(OH)D concentrations were to be raised to 30 ng/mL. Estimated reductions by 25% for myocardial infarction incidence, 35% for stroke incidence, 20 to 35% for cardiovascular disease mortality, and 35% for cancer mortality rates depicted a promising potential for raising serum 25(OH)D. Methods to increase serum 25(OH)D concentrations at the population level could include food fortification with vitamin D3, vitamin D supplementation, improved dietary vitamin D intake, and sensible sun exposure.

[Vitamin C and D supplementation in critically ill patients]

Micronutrient supplementation as part of the medical nutrition therapy for critically ill patients has received much attention in the past few years. Nevertheless, in clinical practice uncertainty remains about the optimal supplementation strategy, including which substance at which dosage should be administered at what time to specific groups of patients. Thus, the aim of this narrative review is to summarize the current evidence and recommendations for the micronutrients vitamin C and vitamin D. The physiological and pathophysiological roles of both vitamins are presented, recently published clinical trials are discussed, and the recommendations of the current guidelines are summarized. In addition, pragmatic tips for use in everyday clinical practice in the intensive care unit are given.

REsCue trial: Randomized controlled clinical trial with extended-release calcifediol in symptomatic COVID-19 outpatients

OBJECTIVES

This double-blind randomized controlled trial investigated raising serum 25-hydroxyvitamin D (25D) with extended-release calcifediol (ERC) on time to symptom resolution in patients with mild to moderate COVID-19.

METHODS

COVID-19 outpatients received oral ERC (300 mcg on days 1-3 and 60 mcg on days 4-27) or placebo (NCT04551911). Symptoms were self-reported daily. Primary end points were raising 25D to ≥50 ng/mL and decreasing resolution time for five aggregated symptoms (three respiratory).

RESULTS

In all, 171 patients were randomized, 160 treated and 134 (65 ERC, 69 placebo) retained. The average age was 43 y (range 18-71), 59% were women. The mean baseline 25D was 37 ± 1 (SE) ng/mL. In the full analysis set (FAS), 81% of patients in the ERC group achieved 25D levels of ≥50 ng/mL versus 15% in the placebo group (P < 0.0001). In the per-protocol (PP) population, mean 25D increased with ERC to 82 ± 4 (SE) ng/mL (P < 0.0001) by day 7; the placebo group trended lower. Symptom resolution time was unchanged in the FAS by ERC (hazard ratio [HR], 0.983; 95% confidence interval [CI], 0.695-1.390; P = 0.922). In the PP population, respiratory symptoms resolved 4 d faster when 25D was elevated above baseline level at both days 7 and 14 (median 6.5 versus 10.5 d; HR, 1.372; 95% CI, 0.945-1.991; P = 0.0962; Wilcoxon P = 0.0386). Symptoms resolved in both treatment groups to a similar extent by study end. Safety concerns including hypercalcemia were absent with ERC treatment.

CONCLUSION

ERC safely raised serum 25D to ≥50 ng/mL in outpatients with COVID-19, possibly accelerating resolution of respiratory symptoms and mitigating the risk for pneumonia. These findings warrant further study.

Effect of Vitamin D3 Supplementation vs. Dietary-Hygienic Measures on SARS-CoV-2 Infection Rates in Hospital Workers with 25-Hydroxyvitamin D3 [25(OH)D3] Levels ≥20 ng/mL

Background: There is scant information on the effect of supplementation with vitamin D3 in SARS-CoV-2 infection cases when patient 25-hydroxyvitamin D3 [25(OH)D3] levels are between 20-100 ng/mL. We aimed to evaluate the effect of supplementation with vitamin D3 vs. dietary-hygienic measures on the SARS-CoV-2 infection rate in participants with serum 25(OH)D3 levels ≥20 ng/mL. Methods: This study was quasi-experimental. We invited hospital workers with 25(OH)D3 levels between 20-100 ng/mL and no previous SARS-CoV-2 infection. They were randomized as follows: treatment options were a) vitamin D3 supplementation (52,000 IU monthly, G1) or b) dietary-hygienic measures (G2). We conducted a 3- to 6-month follow-up of SARS-CoV-2 infections. Participants with 25(OH)D3 levels <20 ng/mL were also analyzed. We divided these latter participants depending on whether they were supplemented (G3) or not (G4). Results: We analyzed 198 participants, with an average age of 44.4 (SD 9) years, and 130 (65.7%) were women. G1 had fewer cases of SARS-CoV-2 infection than G2 after a follow-up of 3- to 6-months (p < 0.05). There were no differences between G3 and G4 at the 3- and 6-month follow-up cutoff points (p > 0.05). Using a mixed effect Cox regression analysis in the 164 participants that completed six months of follow-up, vitamin D3 supplementation appeared to act as a protective factor against SARS-CoV-2 infection (HR 0.21, p = 0.008) in G1 and G2. None of the participants treated with the supplementation doses had serum 25(OH)D3 levels >100 ng/mL. Conclusions: Vitamin D3 supplementation in participants with 25(OH)D3 levels between 20-100 ng/mL have a lower rate of SARS-CoV-2 infection compared with the use of dietary-hygienic measures at six months follow-up.

An update of the effects of vitamins D and C in critical illness

Many critically ill patients are vitamin D and vitamin C deficient and the current international guidelines state that hypovitaminoses should be compensated. However, uncertainty about optimal dosage, timing and indication exists in clinical routine, mainly due to the conflicting evidence. This narrative review discusses both micronutrients with regards to pathophysiology, clinical evidence of benefits, potential risks, and guideline recommendations. Evidence generated from the most recent clinical trials are summarized and discussed. In addition, pragmatic tips for the application of these vitamins in the clinical routine are given. The supplementations of vitamin D and C represent cost-effective and simple interventions with excellent safety profiles. Regarding vitamin D, critically ill individuals require a loading dose to improve 25(OH)D levels within a few days, followed by a daily or weekly maintenance dose, usually higher doses than healthy individuals are needed. For vitamin C, dosages of 100-200 mg/d are recommended for patients receiving parenteral nutrition, but needs may be as high as 2-3 g/d in acutely ill patients.

A combined role for low vitamin D and low albumin circulating levels as strong predictors of worse outcome in COVID-19 patients

PURPOSE

We aimed to assess the combined role of vitamin D and albumin serum levels as predictors of COVID-19 disease progression.

METHODS

We conducted a prospective observational study on adult patients hospitalized for SARS-CoV-2 pneumonia (March-September 2020). Vitamin D and albumin serum levels were measured on admission. These variables were categorized in albumin < 3.5 or ≥ 3.5 g/dL and vitamin D < 30 ng/mL or ≥ 30 ng/mL. We excluded patients with known bone diseases, renal failure, hypercalcemia and/or treated with antiepileptic drugs and steroids, and patients who received previous vitamin D supplementation. A composite outcome including any ventilatory support, PaO₂/FiO₂ ratio, and 60-day mortality was defined.

RESULTS

Sixty-nine patients were enrolled, of whom 50% received non-invasive (NIV) or invasive mechanical ventilation (IMV), 10% died, whereas 89% and 66% presented low albumin and low vitamin D serum levels, respectively. No correlation between vitamin D and albumin levels was found. In multivariable logistic regression analyses adjusted for sex and age-corrected comorbidities, patients having albumin < 3.5 g/dL and vitamin D < 30 ng/mL showed a significant increased risk for all study outcomes, namely NIV/IMV (OR 3.815; 95% CI 1.122-12.966; p = 0.032), NIV/IMV or death (OR 3.173; 95% CI 1.002-10.043; p = 0.049) and PaO₂/FIO₂ ≤ 100 (OR 3.410; 95% CI 1.138-10.219; p = 0.029).

CONCLUSION

The measurement of both vitamin D and serum albumin levels on COVID-19 patients' admission, and their combined evaluation, provides a simple prognostic tool that could be employed to guide prompt clinical decisions.

Hospital and laboratory outcomes of patients with COVID-19 who received vitamin D supplementation: a systematic review and meta-analysis of randomized controlled trials

Coronavirus disease 2019 (COVID-19) has a wide-ranging spectrum of clinical symptoms, from asymptomatic/mild to severe. Recent research indicates that, among several factors, a low vitamin D level is a modifiable risk factor for COVID-19 patients. This study aims to evaluate the effect of vitamin D on hospital and laboratory outcomes of patients with COVID-19.Five databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) and clinicaltrials.gov were searched until July 2022, using relevant keywords/Mesh terms. Only randomized clinical trials (RCTs) that addressed the topic were included. The Cochrane tool was used to assess the studies' risk of bias, and the data were analyzed using the review manager (RevMan 5.4).We included nine RCTs with 1586 confirmed COVID-19 patients. Vitamin D group showed a significant reduction of intensive care unit (ICU) admission (risk ratio = 0.59, 95% confidence interval (CI) [0.41, 0.84], P = 0.003), and higher change in vitamin D level (standardized mean difference = 2.27, 95% CI [2.08, 2.47], P < 0.00001) compared to the control group. Other studied hospital and laboratory outcomes showed non-significant difference between vitamin D and the control group (P ≥ 0.05).In conclusion, vitamin D reduced the risk of ICU admission and showed superiority in changing vitamin D level compared to the control group. However, other outcomes showed no difference between the two groups. More RCTs are needed to confirm these results.

Vitamin D deficiency in British South Asians, a persistent but avoidable problem associated with many health risks (including rickets, T2DM, CVD, COVID-19 and pregnancy complications): the case for correcting this deficiency

High vitamin D deficiency rates, with rickets and osteomalacia, have been common in South Asians (SAs) arriving in Britain since the 1950s with preventable infant deaths from hypocalcaemic status-epilepticus and cardiomyopathy. Vitamin D deficiency increases common SA disorders (type 2 diabetes and cardiovascular disease), recent trials and non-linear Mendelian randomisation studies having shown deficiency to be causal for both disorders. Ethnic minority, obesity, diabetes and social deprivation are recognised COVID-19 risk factors, but vitamin D deficiency is not, despite convincing mechanistic evidence of it. Adjusting analyses for obesity/ethnicity abolishes vitamin D deficiency in COVID-19 risk prediction, but both factors lower serum 25(OH)D specifically. Social deprivation inadequately explains increased ethnic minority COVID-19 risks. SA vitamin D deficiency remains uncorrected after 70 years, official bodies using 'education', 'assimilation' and 'diet' as 'proxies' for ethnic differences and increasing pressures to assimilate. Meanwhile, English rickets was abolished from ~1940 by free 'welfare foods' (meat, milk, eggs, cod liver oil), for all pregnant/nursing mothers and young children (<5 years old). Cod liver oil was withdrawn from antenatal clinics in 1994 (for excessive vitamin A teratogenicity), without alternative provision. The take-up of the 2006 'Healthy-Start' scheme of food-vouchers for low-income families with young children (<3 years old) has been poor, being inaccessible and poorly publicised. COVID-19 pandemic advice for UK adults in 'lockdown' was '400 IU vitamin D/day', inadequate for correcting the deficiency seen winter/summer at 17.5%/5.9% in White, 38.5%/30% in Black and 57.2%/50.8% in SA people in representative UK Biobank subjects when recruited ~14 years ago and remaining similar in 2018. Vitamin D inadequacy worsens many non-skeletal health risks. Not providing vitamin D for preventing SA rickets and osteomalacia continues to be unacceptable, as deficiency-related health risks increase ethnic health disparities, while abolishing vitamin D deficiency would be easier and more cost-effective than correcting any other factor worsening ethnic minority health in Britain.

Vitamin D and COVID-19: Narrative Review after 3 Years of Pandemic

Active vitamin D [1,25(OH)₂D₃-calcitriol] is a secosteroid hormone whose receptor is expressed on all cells of the immune system. Vitamin D has a global anti-inflammatory effect and its role in the management of a SARS-CoV-2 infection has been investigated since the beginning of the COVID-19 pandemic. In this narrative review, the laboratory and clinical results of a vitamin D supplementation have been collected from both open-label and blinded randomized clinical trials. The results are generally in favor of the utility of maintaining the serum concentrations of calcifediol [25(OH)D₃] at around 40 ng/mL and of the absolute usefulness of its supplementation in subjects with deficient serum levels. However, two very recent large-scale studies (one open-label, one placebo-controlled) have called into question the contribution of vitamin D to clinical practice in the era of COVID-19 vaccinations. The precise role of a vitamin D supplementation in the anti-COVID-19 armamentarium requires further investigations in light of the breakthrough which has been achieved with mass vaccinations.

Vitamin D supplementation for the prevention of total cancer incidence and mortality: An updated systematic review and meta-analysis

Introduction

Previous randomized controlled trials (RCTs) and meta-analyses of RCTs evaluating vitamin D supplementation for the prevention of cancer incidence and mortality have found inconsistent results and no meta-analysis has assessed the quality of the evidence available. We, therefore, aimed to perform an updated meta-analysis by including recent large-scale RCTs and assessing the quality of the pooled evidence.

Methods

We searched several databases and trial registers from inception to April 2022. We used a random-effects model to estimate pooled risk ratios (RRs) and 95% confidence intervals (CIs). We used the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) considerations to evaluate the certainty of evidence.

Results

We included 13 RCTs in our study. Vitamin D supplementation had no effect on the risk of total cancer incidence (RR 0.99, 95% CI: 0.94–1.04; I²= 0%), total cancer mortality (RR 0.93, 95% CI: 0.84–1.03; I²= 24%) and total mortality (RR 0.92, 95% CI: 0.82–1.04; I²= 36%). The overall quality of evidence was high for all outcomes.

Discussion

Vitamin D supplementation is ineffective in reducing total cancer incidence and mortality in largely vitamin D-replete older adult populations. Future research should be based on populations with a higher prevalence of vitamin D deficiency and should involve more extended follow-up periods.

Study protocol

PROSPERO database, CRD42021285401.

•

We assessed the effect of vitamin D supplementation on total cancer incidence and mortality.

•

We included 13 randomized controlled trials (RCTs) with 109,543 participants.

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Vitamin D is ineffective in reducing total cancer incidence and mortality in largely vitamin D-replete older adults.

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Future RCTs should focus on populations with a higher prevalence of vitamin D deficiency.

The Effects of Vitamin D Supplementation in COVID-19 Patients: A Systematic Review

Vitamin D has an immune-modulating effect on respiratory tract infections. For this reason, it has been proposed as part of the treatment in COVID-19. Furthermore, vitamin D deficiency has been associated with worse clinical outcomes of this disease. The aim of this systematic review was to determine whether vitamin D supplementation modifies the disease course. Therefore, eleven studies involving randomised clinical trials are analysed, in which groups of COVID-19 patients with or without vitamin D supplementation as part of the treatment are compared. A control group was treated with best available therapy, and in some of the clinical trials, also with a placebo. According to the outcomes, it seems that patients benefit from receiving a daily or maintained in time vitamin D dose regardless of vitamin D serum levels at the beginning of the trial. The administration of a single vitamin D dose does not seem to have any effect on the health status of these patients. However, the outcomes are heterogeneous and larger clinical trials are necessary.

Vitamin D and COVID-19-Revisited

Vitamin D, when activated to 1,25-dihydroxyvitamin D, is a steroid hormone that induces responses in several hundred genes, including many involved in immune responses to infection. Without supplementation, people living in temperate zones commonly become deficient in the precursor form of vitamin D, 25-hydroxyvitamin D, during winter, as do people who receive less sunlight exposure or those with darker skin pigmentation. Studies performed pre-COVID-19 have shown significant but modest reduction in upper respiratory infections in people receiving regular daily vitamin D supplementation. Vitamin D deficiency, like the risk of severe COVID-19, is linked with darker skin colour and also with obesity. Greater risk from COVID-19 has been associated with reduced ultraviolet exposure. Various studies have examined serum 25-hydroxyvitamin D levels, either historical or current, in patients with COVID-19. The results of these studies have varied but the majority have shown an association between vitamin D deficiency and increased risk of COVID-19 illness or severity. Interventional studies of vitamin D supplementation have so far been inconclusive. Trial protocols commonly allow control groups to receive low-dose supplementation that may be adequate for many. The effects of vitamin D supplementation on disease severity in patients with existing COVID-19 are further complicated by the frequent use of large bolus dose vitamin D to achieve rapid effects, even though this approach has been shown to be ineffective in other settings. As the pandemic passes into its third year, a substantial role of vitamin D deficiency in determining the risk from COVID-19 remains possible but unproven.

Variability in response to vitamin D supplementation according to vitamin D metabolism related gene polymorphisms in healthy adults

OBJECTIVE

The aim of this study was to determine the influence of polymorphisms in some key gene actors of the vitamin D (vitD) metabolic pathway on supplementation efficacy.

METHODS

In total, 245 healthy participants were recruited from occupational medicine service in Sahloul University Hospital with vitD deficiency [25(OH)D ≤ 30 ng/ml]. After giving an informed consent, all participants were asked to complete a generalized questionnaire and to follow a detailed personalized supplementation protocol. Genetic study was performed by PCR-RFLP for 15 single nucleotide polymorphisms (SNPs) belonging to DBP, CYP2R1, CYP27B14, CYP24A1 and VDR genes. Statistical study was carried out with SPSS23.0.

RESULTS

Among the studied SNPs, non-response was significantly associated with variant alleles of rs4588 (OR* = 11.51; p < 0.001), rs10766197 (OR* = 6.92; p = 0.008) and rs12794714 (OR* = 5.09; p = 0.004). These three SNPs contributed in 18.8% in response variability with rs4588 being the most influential (10.3%). There was a significant linear negative correlation between baseline 25(OH)D and post supplementation 25(OH)D concentration (r = -0.437; p < 0.001) as well as a linear negative association between the increase in 25(OH)D concentration and GRS (GRS: genetic risk score = the sum of risk alleles) (r = -0.149; p = 0.033).

CONCLUSIONS

DBP-rs4588, CYP2R1-rs10766197 and rs12794714 variants are associated with variations in serum 25(OH)D concentrations and efficacy of response to vitD supplementation in Tunisian adults. Taking into account these variations can help to better adapt vitD intake to ensure a higher response to supplementation.

Vitamin D-binding protein, total, "nonbioavailable," bioavailable, and free 25-hydroxyvitamin D, and mortality in a large population-based cohort of older adults

BACKGROUND

Epidemiological studies consistently find low concentrations of 25-hydroxyvitamin D (25(OH)D) in blood to be associated with increased mortality, and a recent large-scale Mendelian randomization study strongly supports a causal relationship among individuals with low vitamin D status. Evolving evidence suggested that bioavailable or free 25(OH)D may better predict mortality. We aimed to compare the prognostic values of vitamin D-binding protein (VDBP), total, bioavailable, complementary "nonbioavailable", and free 25(OH)D for total and cause-specific mortality in a large population-based cohort study of older adults from Germany.

METHODS

Bioavailable, complementary "nonbioavailable", and free 25(OH)D concentrations were calculated among 5899 participants aged 50-75 years, based on serum concentrations of total 25(OH)D, VDBP, and albumin. The cohort was followed with respect to total and cause-specific mortality from recruitment in 2001-2002 up to the end of 2018. Multivariable Cox proportional hazards regression models were used to assess the associations between various vitamin D biomarkers and mortality, and further stratified by vitamin D status.

RESULTS

During a median follow-up of 17.1 years, 1739 participants died, of whom 575, 584, and 94 died of cardiovascular diseases, cancer, and respiratory diseases, respectively. Very similar inverse associations with total mortality (hazard ratio (HR) per standard deviation decrease: 1.17, 95% confidence interval (CI): 1.11, 1.24 for total 25(OH)D; HR: 1.14, 95% CI: 1.08, 1.21 for bioavailable 25(OH)D; HR: 1.12, 95% CI: 1.06, 1.18 for free 25(OH)D) and cause-specific mortalities were seen for all biomarkers of vitamin D status. The strongest associations were consistently seen for respiratory mortality. These inverse associations were strongest among participants with low vitamin D levels (<50 nmol/L). No significant associations were seen between VDBP and mortality.

CONCLUSIONS

Total, nonbioavailable, bioavailable, and free 25(OH)D showed very similar inverse associations with total and cause-specific mortality, which were strongest among those with low vitamin D status in this large population-based cohort.

COVID-19 and Vitamin D- a Systematic Review

Introduction

The COVID-19 pandemic has strongly affected global healthcare systems. Prior epidemiological studies on different infectious diseases have shown a strong correlation between serum vitamin D levels and the incidence of certain infectious diseases. Vitamin D has an important immunomodulatory effect on innate immunity and exhibits several other mechanisms in the pathogenesis of the cytokine storm, which is one of the main contributing factors to fatality in COVID-19 patients.

Methods

A keyword search was conducted in the PubMed and Google Scholar research databases. The abstracts and/or full texts of selected papers were further evaluated. Articles that fulfilled the inclusion criteria were included in the systematic review.

Results

The 28 studies summarized in this review provide observational findings that vitamin D levels are related to the incidence, severity, and mortality rate of COVID-19 infection. The literature does not suggest that COVID-19 could be eliminated with supplementation of vitamin D, but there are implications that vitamin D deficiency might increase the risk for COVID-19 infection and severity of the disease progression.

Discussion

Current literature and several guidelines support the supplementation of vitamin D as a reasonable strategy for correcting and preventing vitamin D deficiency. The recommended dose for maintaining normal 25(OH)D levels by consensus is 1000 to 2000 IU vitamin D daily for at-risk teens and adults.

Conclusion

Vitamin D supplementation might play an important role in protecting from acute respiratory infections like the SARS CoV2, and in high-risk individuals with COVID 19 from progressing to critical clinical condition and reducing mortality.

The effect of vitamin D supplementation on mortality and intensive care unit admission of COVID-19 patients. A systematic review, meta-analysis and meta-regression

AIMS

The aim of this systematic review and meta-analysis was to investigate the effect of vitamin D supplementation on mortality and admission to intensive care unit (ICU) of COVID-19 patients.

METHODS

A systematic search of PubMed, Google Scholar, Embase, Web of Science and medRxiv with terms relative to vitamin D supplementation and COVID-19 was conducted on 26 March 2021. Comprehensive Meta-Analysis software was used for the quantitative assessment of data and random-effects model was applied. To investigate the association between the dose of vitamin D and the outcomes of interest, meta-regression analysis was performed.

RESULTS

Two thousand and seventy-eight patients from nine studies with data on mortality were included (583 received vitamin D supplementation, while 1495 did not). Sixty-one (10.46%) individuals in the treated group died, compared to 386 (25.81%) in the non-treated group (odds ratio [OR]: 0.597; 95% CI: 0.318-1.121; p = 0.109). Eight hundred and sixty patients from six studies with data on ICU admission were included (369 received vitamin D supplementation, while 491 did not). Forty-five (12.19%) individuals in the treated group were admitted to ICU, compared to 129 (26.27%) in the non-treated group (OR: 0.326; 95% CI: 0.149-0.712; p = 0.005). No significant linear relationship between vitamin D dose and log OR of mortality or log OR of ICU admission was observed.

CONCLUSION

This meta-analysis indicates a beneficial role of vitamin D supplementation on ICU admission, but not on mortality, of COVID-19 patients. Further research is urgently needed to understand the benefit of vitamin D in COVID-19.

Vitamin D: The Missing Nutrient Behind the Two Deadly Pandemics, COVID-19 and Cardiovascular Diseases

The coronavirus (COVID-19) pandemic is claiming millions of lives and creating an additional burden on health care, which is already affected by the rise of non-communicable diseases (NCDs). The scientific community, on the other side, is enormously engaged with studies to best identify the characteristics of the virus and minimize its effect while supporting the fight to contain NCDs, mainly cardiovascular diseases (CVDs), which are contributing hugely to the global death toll. Hence, the roles of vitamin D in COVID-19 immunity and cardiovascular health are gaining traction recently. 

This literature review will mainly focus on summarizing pertinent studies and scientific publications which highlight the association of vitamin D levels with the various outcomes of COVID-19 and CVDs. It will also address how low vitamin D correlates with the epidemiology of CVDs and the inflammatory mechanisms attributed to COVID-19 severity. We believe that our review may open up hindsight perspectives and further discussions among the physicians in tapping the potential of vitamin D supplementation to tackle the morbidity, mortality, and health care cost of the two deadly diseases, COVID-19 and CVDs. 

Long COVID-19 in Children: From the Pathogenesis to the Biologically Plausible Roots of the Syndrome

Long Coronavirus disease-19 (COVID-19) refers to the persistence of symptoms related to the infection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). This condition is described as persistent and can manifest in various combinations of signs and symptoms, such as fatigue, headache, dyspnea, depression, cognitive impairment, and altered perception of smells and tastes. Long COVID-19 may be due to long-term damage to different organs-such as lung, brain, kidney, and heart-caused by persisting viral-induced inflammation, immune dysregulation, autoimmunity, diffuse endothelial damage, and micro thrombosis. In this review, we discuss the potential and biologically plausible role of some vitamins, essential elements, and functional foods based on the hypothesis that an individual's dietary status may play an important adjunctive role in protective immunity against COVID-19 and possibly against its long-term consequences.

The Role of Vitamin D in Supporting Health in the COVID-19 Era

The genomic activity of vitamin D is associated with metabolic effects, and the hormone has a strong impact on several physiological functions and, therefore, on health. Among its renowned functions, vitamin D is an immunomodulator and a molecule with an anti-inflammatory effect, and, recently, it has been much studied in relation to its response against viral infections, especially against COVID-19. This review aims to take stock of the correlation studies between vitamin D deficiency and increased risks of severe COVID-19 disease and, similarly, between vitamin D deficiency and acute respiratory distress syndrome. Based on this evidence, supplementation with vitamin D has been tested in clinical trials, and the results are discussed. Finally, this study includes a biochemical analysis on the effects of vitamin D in the body's defense mechanisms against viral infection. In particular, the antioxidant and anti-inflammatory functions are considered in relation to energy metabolism, and the potential, beneficial effect of vitamin D in COVID-19 is described, with discussion of its influence on different biochemical pathways. The proposed, broader view of vitamin D activity could support a better-integrated approach in supplementation strategies against severe COVID-19, which could be valuable in a near future of living with an infection becoming endemic.

The D-Health Trial: a randomised controlled trial of the effect of vitamin D on mortality

BACKGROUND

The effect of supplementing unscreened adults with vitamin D₃ on mortality is unclear. We aimed to determine whether monthly doses of vitamin D₃ influenced mortality in older Australians.

METHODS

We did a randomised, double-blind, placebo-controlled trial of oral vitamin D₃ supplementation (60 000 IU per month) in Australians 60 years or older who were recruited across the country via the Commonwealth electoral roll. Participants were randomly assigned (1:1), using automated computer-generated permuted block randomisation, to receive one oral gel capsule of either 60 000 IU vitamin D₃ or placebo once a month for 5 years. Participants, staff, and investigators were blinded to study group allocation. The primary endpoint was all-cause mortality assessed in all participants who were randomly assigned. We also analysed mortality from cancer, cardiovascular disease, and other causes. Hazard ratios (HRs) and 95% CIs were generated using flexible parametric survival models. This trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763.

FINDINGS

Between Feb 14, 2014, and June 17, 2015, we randomly assigned 21 315 participants, including 10 662 to the vitamin D group and 10 653 to the placebo group. In 4441 blood samples collected from randomly sampled participants (N=3943) during follow-up, mean serum 25-hydroxy-vitamin D concentrations were 77 (SD 25) in the placebo group and 115 (SD 30) nmol/L in the vitamin D group. Following 5 years of intervention (median follow-up 5·7 years [IQR 5·4-6·7]), 1100 deaths were recorded (placebo 538 [5·1%]; vitamin D 562 [5·3%]). 10 661 participants in the vitamin D group and 10 649 participants in the placebo group were included in the primary analysis. Five participants (one in the vitamin D group and four in the placebo group) were not included as they requested to be withdrawn and their data to be destroyed. The HR of vitamin D₃ effect on all-cause mortality was 1.04 [95% CI 0·93 to 1·18]; p=0·47)and the HR of vitamin D₃ effect on cardiovascular disease mortality was 0·96 (95% CI 0·72 to 1·28; p=0·77). The HR for cancer mortality was 1·15 (95% CI 0·96 to 1·39; p=0·13) and for mortality from other causes it was 0·83 (95% CI 0·65 to 1·07; p=0·15). The odds ratio for the per-protocol analysis was OR 1·18 (95% CI 1·00 to 1·40; p=0·06). In exploratory analyses excluding the first 2 years of follow-up, those randomly assigned to receive vitamin D had a numerically higher hazard of cancer mortality than those in the placebo group (HR 1·24 [95% CI 1·01-1·54]; p=0·05).

INTERPRETATION

Administering vitamin D₃ monthly to unscreened older people did not reduce all-cause mortality. Point estimates and exploratory analyses excluding the early follow-up period were consistent with an increased risk of death from cancer. Pending further evidence, the precautionary principle would suggest that this dosing regimen might not be appropriate in people who are vitamin D-replete.

FUNDING

The D-Health Trial is funded by National Health and Medical Research Council.

Vitamin D supplementation and clinical outcomes in COVID-19: a systematic review and meta-analysis

PURPOSE

To provide a precise summary and collate the hitherto available clinical evidence on the effect of vitamin D supplementation on clinical outcomes in COVID-19 patients.

METHODS

PubMed/MEDLINE, Scopus, and Web of Science databases were systematically searched using appropriate keywords till June 8, 2021, to identify observational studies and randomized controlled trials (RCTs) reporting adverse clinical outcomes (ICU admission and/or mortality) in COVID-19 patients receiving vitamin D supplementation vs. those not receiving the same. Both prior use and use of vitamin D after COVID-19 diagnosis were considered. Unadjusted/adjusted pooled odds ratio (OR) with 95% confidence intervals (CI) were calculated (PROSPERO registration number CRD42021248488).

RESULTS

We identified 13 studies (10 observational, 3 RCTs) pooling data retrieved from 2933 COVID-19 patients. Pooled analysis of unadjusted data showed that vitamin D use in COVID-19 was significantly associated with reduced ICU admission/mortality (OR 0.41, 95% CI: 0.20, 0.81, p = 0.01, I2 = 66%, random-effects model). Similarly, on pooling adjusted risk estimates, vitamin D was also found to reduce the risk of adverse outcomes (pooled OR 0.27, 95% CI: 0.08, 0.91, p = 0.03, I2 = 80%, random-effects model). Subgroup analysis showed that vitamin D supplementation was associated with improved clinical outcomes only in patients receiving the drug post-COVID-19 diagnosis and not in those who had received vitamin D before diagnosis.

CONCLUSIONS

Vitamin D supplementation might be associated with improved clinical outcomes, especially when administered after the diagnosis of COVID-19. However, issues regarding the appropriate dose, duration, and mode of administration of vitamin D remain unanswered and need further research.

Vitamin D: role in chronic and acute diseases

Vitamin D is involved in bone health by promoting calcium absorption in the gut and maintaining serum calcium and phosphate concentrations, and by its action on bone growth and reorganization through osteoblasts and osteoclasts cells. Moreover, during the last three decades, novel actions of vitamin D have been discovered. Several systematic reviews and meta-analyses have shown links between serum vitamin D levels and non-communicable diseases. In line with these findings, a wide number of studies have suggested associations of vitamin D deficiency (VDD) with respiratory tract infections, osteoporosis, and other chronic and metabolic diseases such as obesity, metabolic syndrome, type 2 diabetes mellitus (T2DM), cancer, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD). Vitamin D also exerts important actions in the clinical course of infectious and other acute diseases, particularly respiratory bacterial infections, tuberculosis, and virus infections, e.g., those generated by human immunodeficiency and SARS-CoV-2 (COVID-19) viruses. The present article aimed to update the role of vitamin D in chronic and acute diseases.

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To know the role of vitamin D in the prevention and treatment of non-communicable chronic diseases.

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To understand how vitamin D deficiency is related to obesity, insulin resistance and metabolic syndrome, type 2 diabetes, cancer, rheumatoid arthritis, osteoporosis, chronic pulmonary obstructive disease, and inflammatory bowel disease.

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To know the function of vitamin D in the prevention and treatment of acute infectious diseases of bacterial and viral origins, namely respiratory infections.

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To understand the role of vitamin D in the prevention of HIV and SARS-Cov2 infections

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To know how vitamin D status affects the course of critical illness diseases

The Interaction of Vitamin D and Corticosteroids: A Mortality Analysis of 26,508 Veterans Who Tested Positive for SARS-CoV-2

This data-based cohort consisted of 26,508 (7%) United States veterans out of the 399,290 who tested positive for SARS-CoV-2 from 1 March to 10 September 2020. We aimed to assess the interaction of post-index vitamin D (Vit D) and corticosteroid (CRT) use on 30-day mortality among hospitalized and non-hospitalized patients with coronavirus disease 2019 (COVID-19). Combination Vit D and CRT drug use was assessed according to four multinomial pairs (-|+, -|-, +|+, +|-). Respective categorical effects were computed on a log-binomial scale as adjusted relative risk (aRR). Approximately 6% of veterans who tested positive for SARS-CoV-2 died within 30 days of their index date. Among hospitalized patients, a significantly decreased aRR was observed for the use of Vit D in the absence of CRTs relative to patients who received CRTs but not Vit D (aRR = 0.30; multiplicity corrected, p = 0.0004). Among patients receiving systemically administered CRTs (e.g., dexamethasone), the use of Vit D was associated with fewer deaths in hospitalized patients (aRR = 0.51) compared with non-hospitalized patients (aRR = 2.5) (P-for-Interaction = 0.0071). Evaluating the effect of modification of these compounds in the context of hospitalization may aid in the management of COVID-19 and provide a better understanding of the pathophysiological mechanisms underlying this and future infectious disease outbreaks.

The Exposome and Immune Health in Times of the COVID-19 Pandemic

Growing evidence supports the importance of lifestyle and environmental exposures-collectively referred to as the 'exposome'-for ensuring immune health. In this narrative review, we summarize and discuss the effects of the different exposome components (physical activity, body weight management, diet, sun exposure, stress, sleep and circadian rhythms, pollution, smoking, and gut microbiome) on immune function and inflammation, particularly in the context of the current coronavirus disease 2019 (COVID-19) pandemic. We highlight the potential role of 'exposome improvements' in the prevention-or amelioration, once established-of this disease as well as their effect on the response to vaccination. In light of the existing evidence, the promotion of a healthy exposome should be a cornerstone in the prevention and management of the COVID-19 pandemic and other eventual pandemics.

Vitamin D: Bolus Is Bogus-A Narrative Review

In this review we summarize the impact of bolus versus daily dosing of vitamin D on 25(OH)D and 1,25(OH)2D levels, as well as on key countervailing factors that block vitamin D functions at the cellular level. Further, we discuss the role of bolus versus daily dosing of vitamin D for several health outcomes, including respiratory infections and coronavirus disease 2019 (COVID-19), rickets, falls and fractures, any cancer, and cancer-related mortality. This discussion appears timely because bolus doses continue to be tested for various disease outcomes despite a growing amount of evidence suggesting lack of efficacy or even detrimental effects of bolus dosing of vitamin D for outcomes where daily dosing at modest levels was effective in the vitamin D deficient. As a result, these discordant results may bias health recommendations for vitamin D if the recommendations are based on meta-analyses combining both daily and bolus dosing trials. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Vitamin D oral intermittent treatment (DO IT) study, a randomized clinical trial with individual loading regimen

Comparison of several regimens of oral vitamin D including an individually calculated loading regimen with the aim of achieving serum values > 75 nmol/l. Interventional, randomized, 3-arm study in vitamin D-deficient outpatients. Participants were allocated to supplementation of 24,000 IU vitamin D monthly over three months, using either a monthly drinking solution (Vi-De 3) or capsule (D3 VitaCaps), or an individualized loading regimen with the capsules taken weekly. For the loading regimen, the cumulative dose was calculated according to baseline 25-hydroxy-vitamin D (25(OH)D) serum value and body weight. Main inclusion criteria were age ≥ 18 years and 25(OH)D serum concentration < 50 nmol/l. The primary outcome was 25(OH)D serum concentration one week after treatment termination. Secondary endpoints were patient's preferences and adverse events. Full datasets were obtained from 52 patients. Mean 25(OH)D values were statistically significant higher after a loading regimen compared to a monthly administration of 24,000 IU vitamin D (76.4 ± 15.8 vs 61.4 ± 10.8 nmol/l; p < 0.01). All patients treated with the loading regimen reached sufficient 25(OH)D values > 50 nmol/l. Serum 25(OH)D values > 75 nmol/l were observed more frequently in patients taking the loading regimen (47% vs 11% drinking solution vs 12% capsules). Vitamin D-related adverse effects did not occur in any treatment groups. Capsules were preferred by 88.5% of the patients. Compared to treatments with monthly intake of 24,000 IU vitamin D, the intake of an individually calculated weekly loading regimen was able to raise serum concentrations > 50 nmol/l in all cases within a safe range.

Vitamin D and acute and severe illness - a mechanistic and pharmacokinetic perspective

The COVID-19 pandemic has generated high interest in factors modulating risk of infection, disease severity and recovery. Vitamin D has received interest since it is known to modulate immune function and vitamin D deficiency is associated with increased risk of respiratory infections and adverse health outcomes in severely ill patients. There are no population representative data on the direct relationship between vitamin D status and SARS-CoV-2 infection risk and severity of COVID-19. Data from intervention studies are limited to 4 studies. Here we summarise findings regarding vitamin D status and metabolism and their alterations during severe illness, relevant to COVID-19 patients. Further, we summarise vitamin D intervention studies with respiratory disease outcomes and in critically ill patients and provide an overview of relevant patient and population guidelines. Vitamin D deficiency is highly prevalent in hospitalised patients, particularly when critically ill including those with COVID-19. Acute and critical illness leads to pronounced changes in vitamin D metabolism and status, suggestive of increased requirements. This needs to be considered in the interpretation of potential links between vitamin D status and disease risk and severity and for patient management. There is some evidence that vitamin D supplementation decreases the risk of respiratory tract infections, while supplementation of ICU patients has shown little effect on disease severity or length of treatment. Considering the high prevalence of deficiency and low risks associated with supplementation, pro-actively applying current population and patient management guidelines to prevent, monitor and correct vitamin D deficiency is appropriate.

The Effect of Bolus Vitamin D3 Supplementation on Distal Radius Fracture Healing: A Randomized Controlled Trial Using HR-pQCT

Vitamin D is an important factor in bone metabolism. Animal studies have shown a positive effect of vitamin D₃ supplementation on fracture healing, but evidence from clinical trials is inconclusive. A randomized controlled trial was performed to assess the effects of vitamin D₃ supplementation on fracture healing using HR-pQCT-based outcome parameters. Thirty-two postmenopausal women with a conservatively treated distal radius fracture were included within 2 weeks postfracture and randomized to a low-dose (N = 10) and a high-dose (N = 11) vitamin D intervention group receiving a 6-week bolus dose, equivalent to 700 and 1800 IU vitamin D₃ supplementation per day, respectively, in addition to a control group (N = 11) receiving no supplementation. After the baseline visit 1-2 weeks postfracture, follow-up visits were scheduled at 3-4, 6-8, and 12 weeks postfracture. At each visit, HR-pQCT scans of the fractured radius were performed. Cortical and trabecular bone density and microarchitectural parameters and microfinite element analysis-derived torsion, compression, and bending stiffness were assessed. Additionally, serum markers of bone resorption (CTX) and bone formation (PINP) were measured. Baseline serum levels of 25OHD₃ were <50 nmol/L in 33% of all participants and <75 nmol/L in 70%. Compared with the control group, high-dose vitamin D₃ supplementation resulted in a decreased trabecular number (regression coefficient β: -0.22; p < 0.01) and lower compression stiffness (B: -3.63; p < 0.05, together with an increase in the bone resorption marker CTX (B: 0.062; p < 0.05). No statistically significant differences were observed between the control and low-dose intervention group. In conclusion, the bolus equivalent of 700 U/day vitamin D₃ supplementation in a Western postmenopausal population does not improve distal radius fracture healing and an equivalent dose of 1800 IU/day may be detrimental in restoring bone stiffness during the first 12 weeks of fracture healing. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Vitamin D in critical care: where are we now and what is next?

PURPOSE OF REVIEW

To summarize the recent evidence on the role of vitamin D deficiency in critically ill patients and emerging data claiming a role of vitamin D in COVID-19.

RECENT FINDINGS

Vitamin D is a strong predictor for worse outcomes in critically ill patients, and as well in COVID-19. The vitamin D content in typical nutrition regimes is lower than what is recommended for the general population. Although its supplementation has been shown to reduce respiratory tract infections, asthma exacerbations and mortality risk in noncritically ill patients, its role in the acute setting is not yet clear. Several small intervention trials have shown interesting results in COVID-19, and larger studies are ongoing.

SUMMARY

Although research on this topic is still ongoing, it appears reasonable to recommend at least the standard vitamin dose for the healthy population (600--800 IU of native vitamin D3). Many questions remain on the actual role, the best metabolite, regime, and so forth. However, the role for vitamin D in bone health is clear. Elderly ICU survivors have a high risk for osteoporosis/fractures, so at least in this population, an optimal vitamin D status should be targeted.