Vitamin D supplementation to prevent acute respiratory infections: individual participant data meta-analysis

Vitamin D status in children with mild, moderate, or severe confirmed COVID-19: systematic-review and meta-analysis

Background

Vitamin D acts as a pro-hormone with a wide range of beneficial effects. It is reported that vitamin D deficiency is a risk factor for COVID-19 severity in children. In the present study, we decided to assess 25 hydroxy (OH) vitamin D status in children with mild, moderate, or severe confirmed COVID-19 and also compare them with those of a healthy control group using existing data.

Methods

Relevant studies were extracted using online international databases including Scopus, Science Direct, PubMed, Web of Science, ProQuest, and Google Scholar search engine between Jan 2019 and 2024. The quality of all papers is determined by the NOS checklist. Heterogeneity between the results of primary studies was evaluated with the I-square index. Egger's test, funnel plot, and sensitivity analysis were applied. The statistical analysis was done using Stata version 17.

Results

In 12 documents, the status of vitamin D was examined between case and control groups. By combining the results of these studies using random effect model, the standardized mean difference (SMD) vitamin D level in the COVID-19 children compared to the control group was estimated to be -0.88 (98% CI: -1.24, -0.51), which was statistically significant. In the present study, the odd ratio of vitamin D deficiency and vitamin D disorder (insufficiency and deficiency) in children with moderate COVID-19 compared to asymptomatic children with COVID-19 were estimated to be 3.58 (1.10, 11.63) and 2.52 (0.99, 6.41) respectively which was higher than in asymptomatic children with COVID-19. In addition, vitamin D deficiency and vitamin D disorder in children with moderate COVID-19 compared to the children with mild COVID-19 were estimated to be 2.12 (0.90, 4.98) and 1.82 (0.78, 4.22) respectively, which was higher than in children with mild COVID-19. Also, vitamin D deficiency and vitamin D disorder in children with mild COVID-19 compared to asymptomatic children with COVID-19 were estimated to be 2.02 (0.60, 6.78) and 1.64 (0.53, 5.07) respectively, which was higher than in asymptomatic children.

Conclusions

Combining the results of these studies, the effect size of the relationship between vitamin D and COVID-19 in children is significant. During the COVID-19 pandemic (except for the Omicron peak), children were less affected by the severity of COVID-19. The standardized mean difference (SMD) vitamin D level in children with COVID-19 was significantly 0.88 units lower than the control group. Also, the odds ratio of moderate COVID-19 in children with vitamin D deficiency was significantly 3.58 times higher than in asymptomatic children with COVID-19.

The Importance of Lung Innate Immunity During Health and Disease

The lung is a vital organ for the body as the main source of oxygen input. Importantly, it is also an internal organ that has direct contact with the outside world. Innate immunity is a vital protective system in various organs, whereas, in the case of the lung, it helps maintain a healthy, functioning cellular and molecular environment and prevents any overt damage caused by pathogens or other inflammatory processes. Disturbances in lung innate immunity properties and processes, whether over-responsiveness of the process triggered by innate immunity or lack of responses due to dysfunctions in the immune cells that make up the innate immunity system of the lung, could be correlated to various pathological conditions. In this review, we discuss globally how the components of lung innate immunity are important not only for maintaining lung homeostasis but also during the pathophysiology of notable lung diseases beyond acute pulmonary infections, including chronic obstructive pulmonary disease (COPD), asthma, and pulmonary fibrosis.

Vitamin D: A key player in COVID-19 immunity and lessons from the pandemic to combat immune-evasive variants

As of the 7th of July 2024, 775,754,322 confirmed cases of COVID-19, including 7,053,902 deaths worldwide, had been reported to the WHO (World Health Organization). Nevertheless, untill the 15th of July 2024, a total of 13,578,710,228 vaccine doses had been administered, with almost no country spared from COVID-19 attacks. The pathophysiology of this virus is complicated, and several symptoms require a deep understanding of the actual mechanisms. It is unclear why some patients develop severe symptoms while others do not, although literature suggests a role for vitamin D. Vitamin D plays a crucial role in the infection or in ameliorating the severity of symptoms. The mechanism of action of vitamin D and vitamin D deficiency (VDD) is well understood. VDD is associated with increased hospitalization of severely ill patients and increased levels of COVID-19-caused mortality. Recent studies suggest that vitamin D levels and genetic variations in the vitamin D receptor (VDR) gene significantly impact the severity and outcomes of COVID-19, especially in the infections caused by Delta and Omicron variants. Furthermore, VDD causes immune system dysregulation upon infection with SARS-CoV-2, indicating that vitamin D sufficiency is crucial in fighting against COVID-19 infection. The therapeutic effect of vitamin D raises interest in its potential role as a prophylactic and treatment adjunct. We evaluate the immunomodulatory effects of vitamin D and its ability to enhance the efficacy of new antiviral drugs like molnupiravir and paxlovid against SARS-CoV-2. This review discusses the role of vitamin D sufficiency and VDD in COVID-19 initiation and progression, emphasizing the molecular mechanisms by which vitamin D exerts its actions as a proactive step for the next pandemic. However, there is still no clear evidence of vitamin D's impact on prevention and treatment, leading to contradictory findings. Therefore, large-scale randomized trials are required to reach a definitive conclusion. A bibliometric analysis of publications related to vitamin D, immunity, and COVID-19 revealed a significant increase in research activity in this area, particularly in 2020-2024, underscoring the growing recognition of vitamin D's potential role in the context of the pandemic.

Assessing the Impact of Vitamin D Supplementation on Respiratory Infections in Children and Adolescents: A Cross-Sectional Study

BACKGROUND AND OBJECTIVES

Recent studies suggest that vitamin D supplementation and higher serum 25-hydroxyvitamin D (25-OHD) concentrations may reduce the incidence of respiratory infections in children and adolescents. This cross-sectional study aimed to evaluate the association between different concentrations of vitamin D supplementation, serum 25-OHD concentrations, and the frequency of respiratory infections among individuals aged 1 to 18 years, for a duration of 2 years.

METHODS

Concerning sun exposure in relation to vitamin D, the study took place in Romania, at approximately 45-degree northern latitude. A total of 194 patients were divided into groups based on weekly vitamin D supplementation (<400 IU, 400-800 IU, >800 IU), serum 25-OHD concentrations (<20 ng/mL, 20-30 ng/mL, >30 ng/mL), and age (<6 years, 6-12 years, 12-18 years). The overall incidence of respiratory infections was 41.2%.

RESULTS

Participants receiving >800 IU/week had a significantly lower incidence of infections (16.7%) compared to those receiving <400 IU/week (60.0%, p < 0.001). Similarly, participants with serum 25-OHD concentrations >30 ng/mL had an infection rate of 16.7%, compared to 61.4% in those with concentrations <20 ng/mL (p < 0.001). Age-specific analyses revealed that the protective effect of vitamin D was most pronounced in children under 6 years old. Logistic regression showed that higher vitamin D supplementation and serum 25-OHD concentrations were independently associated with reduced odds of respiratory infections (OR = 0.25 and OR = 0.22, respectively, p < 0.001).

CONCLUSIONS

These findings support the potential role of vitamin D supplementation in preventing respiratory infections in the pediatric population.

Ethnic Differences in Response to Oral Vitamin D Supplementation: A Systematic Review and Meta-analysis

CONTEXT

Individual variability in oral vitamin D supplement response hinders the understanding of its clinical impact, and while ethnicity has been implicated in this variability it has not been well described.

OBJECTIVE

The aim was to systematically assess the impact of ethnicity on response to oral vitamin D supplementation.

DATA SOURCE

The Web of Science and PubMed databases were searched for articles published from 1960 to the end of 2020. All trials in adults measuring 25(OH)D3 blood levels were included.

DATA EXTRACTION

Two reviewers independently extracted the data from the eligible studies. The change in 25(OH)D3 blood levels (95% CI) and P values were extracted, and grouped according to ethnicity, then subjected to random-effects meta-analysis. The primary outcome measurement was mean serum 25(OH)D3 levels and the secondary outcome was dose-adjusted mean serum 25(OH)D3 levels, both compared with baseline.

DATA ANALYSIS

A total of 18 studies were identified, and data from 1131 participants were extracted. Body mass index (BMI) and dose were significant covariates (Pearson correlation coefficient, P = .016 and .017) and were normalized in the meta-analysis to minimize heterogeneity, but latitude was not (P = .66). Meta-analysis showed an effect of ethnicity on dose and BMI-adjusted mean serum 25(OH)D3 levels compared with baseline (P < .00001, I2 = 98%). Asian and White study participants demonstrated a statistically higher increase in dose and BMI-adjusted 25(OH)D3 blood levels (183 nmol/L [95% CI, 163-203] and 173 nmol/L [95% CI, 152-194], respectively), compared with Arab and Black study participants (37 nmol/L [95% CI, 35-39] and 99 nmol/L [95% CI, 90-108]) using repeated t tests. Sensitivity analysis demonstrated that these findings were not impacted by potential study bias or the inclusion of immigrant populations.

CONCLUSION

Ethnicity had an impact on oral vitamin D response. Further prospective studies should examine if ethnicity-based dose stratification in both clinical practice and clinical trials is warranted.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023410076.

New randomized controlled trials on micronutrients in critical care nutrition: A narrative review

There has been increasing interest in the role of micronutrient supplementation in critical care. This narrative review summarizes the recent studies on micronutrients in critically ill patients. We searched two databases for primary randomized controlled trials that investigated the effects of micronutrient supplementation in patients with critical illness published from January 2021 to August 2023. Personal files, reference lists of included studies, and previous reviews were also screened. Twelve studies reported on vitamin C, four studies on vitamin D, three studies on thiamin, two studies on multivitamins, and one study on cobalamin. The therapeutic effects of vitamin C appear mixed, although vitamin C monotherapy appears more promising than vitamin C combination therapy. Intramuscular administration of vitamin D appeared to lower mortality, mechanical ventilation duration, and intensive care unit stay, whereas enteral administration showed limited clinical benefits. Intravenous thiamin was not associated with improved outcomes in patients with septic shock or hypophosphatemia. Preliminary evidence suggests reduced vasopressor dose with cobalamin. Decreased disease severity and hospital stay in patients with COVID-19 with vitamins A-E requires further investigation, whereas providing solely B-group vitamins did not demonstrate therapeutic effects. It is currently premature to endorse the provision of high-dose micronutrients in critical illness to improve clinical outcomes. This review may help to inform the design of future trials that will help better elucidate the optimal dosage and form of micronutrients, methods of administration, and subgroups of patients with critical illness who may most benefit.

Patterns of Dietary Supplement Use during the COVID-19 Pandemic in Poland: Focus on Vitamin D and Magnesium

Background: The COVID-19 pandemic has brought significant attention to the role of dietary supplements, particularly Vitamin D, in enhancing immunity and possibly mitigating the severity of the disease. The pandemic has highlighted the importance of nutritional health in preventing severe outcomes from infections. Objective: This study aimed to assess consumption patterns of dietary supplements, with a focus on Vitamin D, among the Polish population during the COVID-19 pandemic and to identify the demographic factors influencing these patterns. Methods: An anonymous survey was conducted in March 2021 among 926 pharmacy patients in Poland. The study analyzed the use of dietary supplements such as vitamin D, magnesium, and others in relation to variables like age, gender, and education level. Statistical analyses were performed using the Pearson chi-square test. Results: The study revealed that 77.1% of the respondents reported using dietary supplements, with Vitamin D being the most frequently mentioned, used by 64.6% of participants. Magnesium was also widely used, with a higher overall prevalence of 67.3%, making it the most commonly consumed supplement. The use of supplements was significantly higher among women and individuals with higher education. Younger age groups, particularly those aged 18-30, were more likely to use supplements. Conclusions: The use of supplements was significantly higher among women, individuals with higher education, and those aged 18-30. However, the findings also indicate a growing awareness and increased use across the general population. This trend reflects increased public awareness of the potential health benefits of these supplements in boosting immunity. However, the study also highlights the need for public education on the risks of over-supplementation and the importance of appropriate dosages.

Assessment of Supplementation with Different Biomolecules in the Prevention and Treatment of COVID-19

Consequences of the disease produced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have led to an urgent search for preventive and therapeutic strategies. Besides drug treatments, proposals have been made for supplementation with biomolecules possessing immunomodulatory and antioxidant properties. The objective of this study was to review published evidence on the clinical usefulness of supplementation with vitamin D, antioxidant vitamins (vitamin A, vitamin E, and vitamin C), melatonin, lactoferrin and natural products found in food (curcumin, luteolin, ginger, allicin, magnesium and zinc) as supplements in SARS-CoV-2 infection. In general, supplementation of conventional treatments with these biomolecules has been found to improve the clinical symptoms and severity of the coronavirus disease (COVID-19), with some indications of a preventive effect. In conclusion, these compounds may assist in preventing and/or improving the symptoms of COVID-19. Nevertheless, only limited evidence is available, and findings have been inconsistent. Further investigations are needed to verify the therapeutic potential of these supplements.

Vitamin D supplementation for prevention of acute respiratory infections in older adults: A systematic review and meta-analysis

BACKGROUND

Acute respiratory infections (ARIs) have a substantial impact on morbidity, healthcare utilization, and functional decline among older adults. Therefore, we systematically reviewed evidence from randomized controlled trials (RCTs) to evaluate the efficacy and safety of vitamin D supplementation in preventing ARIs in older adults.

METHODS

PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov were searched until 1 February 2024. RCTs evaluating the use of vitamin D supplements to protect older adults from ARIs were included. Two reviewers independently screened papers, extracted the data and assessed the risk of bias. Data were summarised as relative risks (RRs) or odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Random effects meta-analyses were used to synthesise the results. GRADE was used to evaluate the quality of evidence. All the analysis were performed with Stata version 17.

RESULTS

Twelve trials (41552 participants) were included in the meta-analysis. It showed that vitamin D supplementation probably does not reduce the incidence of ARIs (RR, 0.99; 95% CI, 0.97-1.02, I2 = 0%; moderate certainty). No significant effect of vitamin D supplementation on the risk of ARI was observed for any of the subgroups defined by baseline 25(OH)D concentration, control treatments, dose frequency, study duration, and participants' condition. However, there was a possibility, although not statistically significant, that vitamin D may reduce the risk of ARI in patients with a baseline 25(OH)D concentration <50 nmol/L (OR, 0.90; 95% CI, 0.79-1.04, I2 = 14.7%). Additionally, vitamin D supplements might result in little to no difference in death due to any cause, any adverse event, hypercalcinemia, and kidney stones.

CONCLUSIONS

Vitamin D supplementation among older adults probably results in little to no difference in the incidence of ARIs. However, further evidence is needed, particularly for individuals with vitamin D deficiency and populations residing in low and middle income countries.

TRIAL REGISTRATION

This study was registered on PROSPERO (CRD42023451265).

Impact of 25-hydroxy vitamin D levels in severe acute respiratory syndrome coronavirus 2 patients with respect to clinical and biochemical profile: An experience from a tertiary care hospital

INTRODUCTION

Among the many micronutrients, Vitamin D deficiency has been associated with the severity of Severe Acute Respiratory Syndrome Coronavirus 2 patients.

DESIGN AND METHODS

A retrospective observational study was conducted on Severe acute respiratory syndrome coronavirus 2 patients admitted to a tertiary care hospital between April 5, 2021, and May 5, 2021.

RESULTS

Among 285 patients,77.2 % of the patients who stayed for more than 14 days were either Vitamin D insufficient or deficient [P value < 0.05]. In our study, the mean oxygen saturation at admission was 85.7 % in the Vitamin D deficiency group compared to 95.6 % in Vitamin D sufficiency patients [P value < 0.05]. Mean serum ferritin was 398 ng/ml in the Vitamin D deficiency group compared to 393 ng/ml in Vitamin D sufficiency patients [P value > 0.05]. The mean C-reactive protein was 107.6 mg/ml in the Vitamin D deficiency group compared to 21.8 ng/ml in Vitamin D sufficiency patients [P value < 0.05]. The mean D-Dimer was 2268 ng/ml in the Vitamin D deficiency group compared to 781 ng/ml in Vitamin D sufficiency patients [P value < 0.05]. In the non-survivor group,97.4 % were Vitamin D deficient and insufficient. Only 2 % of the patients who survived were Vitamin D deficient [P value < 0.05].

CONCLUSION

We observed that low 25-hydroxy Vitamin D levels were associated with lower oxygen saturation and higher acute physiology and chronic health evaluation II scores, requiring a more extended stay in the hospital. C-reactive protein and D-dimers were significantly higher in Vitamin D deficient patients, suggesting severe disease. We did not find statistically significant findings in the case of the correlation of serum ferritin levels with Vitamin D status.

Association between serum 25-hydroxyvitamin D and vitamin D dietary supplementation and risk of all-cause and cardiovascular mortality among adults with hypertension

BACKGROUND

The relationship between vitamin D status and mortality among adults with hypertension remains unclear.

METHODS

This prospective cohort study involved a sample of 19,500 adults with hypertension who participated in the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018. We utilized a weighted COX proportional hazard model to assess the association between vitamin D status and mortality. This statistical model calculates hazard ratios (HR) and their corresponding 95% confidence intervals (95% CI).

RESULTS

The study indicated that lower serum 25(OH)D concentration was associated with an increased risk of all-cause mortality among individuals with hypertension. Specially. Those with concentrations between 25.0 and 49.9 nmol/L (HR = 1.71, 95%CI = 1.22-2.40) and less than 25.0 nmol/L (HR = 1.97, 95%CI = 1.15-3.39) had higher hazard ratios for all-cause mortality. Individuals with hypertension who took vitamin D supplements had a lower risk of all-cause mortality, but not the risk of CVD mortality (HR 0.75, 95%CI 0.54-1.03), compared to those who did not supplement (HR = 0.76, 95%CI = 0.61-0.94). Subgroup analysis further revealed that vitamin D supplementation was associated with a reduced risk of all-cause mortality among individuals without diabetes (HR = 0.65, 95%CI = 0.52-0.81) and individuals without CVD (HR = 0.75, 95%CI = 0.58-0.97), and a decreased risk of CVD mortality among individuals without diabetes (HR = 0.63, 95%CI = 0.45-0.88) and without CVD (HR = 0.61, 95%CI = 0.40-0.92). Furthermore, higher-dose vitamin D supplementation was also associated with a greater reduction in all-cause mortality among hypertensive individuals, and there was the potential synergistic effect of combining normal-dose calcium and vitamin D supplementation, showing a superior effect on mortality compared to low-dose supplementation in adults with hypertension.

CONCLUSIONS

This prospective cohort study demonstrated a significant association between lower serum 25 (OH)D concentration and increased all-cause mortality among adults with hypertension. Furthermore, the study found that vitamin D supplementation had a strong and significantly positive correlation with reduced all-cause and CVD mortality among hypertensive individuals without diabetes or CVD. This positive correlation suggests that vitamin D supplementation could potentially be an effective strategy to reduce the risk of mortality in this specific group of people.

A Case Study of Vitamin D Supplementation Therapy and Acute Respiratory Tract Infection

BACKGROUND

Low serum concentrations of 25-hydroxyvitamin D correlate with higher susceptibility to acute respiratory tract infections (ARTIs). The case study presented here aims at sheding light on the correlation between vitamin D levels, the vitamin D supplement dose, and the incidence of ARTIs.

CASE REPORT

A 23-year-old female patient with a vitamin D insufficiency was able to successfully increase her vitamin D levels from 45.60 nmol/l to 85.91 nmol/l (reference ranges 75-200 nmol/l) through the use of supplements. However, it was surprising to observe a decrease in vitamin D levels even though the patient continued taking supplements. Further examination indicated that the patient was experiencing common symptoms of an acute respiratory tract infection (ARTI). This case highlights the intricate connection between ARTIs and vitamin D intake.

CONCLUSION

This case study clearly demonstrates the intricate connection between vitamin D levels, supplement treatment, and ARTIs. The observed decrease in vitamin D levels during the course of supplementation, while the patient was suffering from an ARTI, suggests that respiratory infections may affect vitamin D metabolism.

Association of vitamin D with HIV infected individuals, TB infected individuals, and HIV-TB co-infected individuals: a systematic review and meta-analysis

Background

Vitamin D deficiency (VDD) is a worldwide disease. VDD is also associated with an increased risk of HIV-related comorbidities and mortality, and patients have a tendency to develop active tuberculosis compared to those with latent tuberculosis infection. Vitamin D supplementation may modulate HIV replication, improve TB inflammation and reduce progression of HIV-TB co-infection.

Methods

We meta-analyzed individual participant data from cohort studies, cross-sectional study, and RCTs of vitamin D in HIV group, TB group, and HIV-TB group. The primary outcomes were differences in vitamin D level and VDD prevalence between three groups, the secondary outcomes were CD4 count, HIV viral load, time to sputum smear conversion, time to culture conversion, relapse, morality, and TB score.

Results

For vitamin D levels, the overall mean difference (MD) between HIV group and TB group was -0.21 (95% CI, -20.80-20.38; p = 0.9, I2 = 84%), HIV group and HIV-TB group was 0.87 (95% CI, -11.45-13.20; p = 0.89, I2 = 87%), and TB group and HIV-TB group was 1.17 (95% CI, -5.21-7.55; p = 0.72, I2 = 85%). For vitamin D deficiency prevalence, the overall odds ratio (OR) for HIV group versus TB group was 1.23 (95% CI, 0.46-3.31; p = 0.68; I2 = 70%), HIV group versus HIV-TB group was 1.53 (95% CI, 1.03-2.29; p = 0.04; I2 = 0%), and TB group versus HIV-TB group was 0.85 (95% CI, 0.61-1.20; p = 0.36; I2 = 22%). In HIV-TB group, the overall OR for vitamin D group versus placebo group was 0.78 (95% CI, 0.34-1.67; p = 0.52; I2 = 60%).

Conclusion

Our findings indicated that there were no variations in vitamin D levels between three groups. The prevalence of vitamin D deficiency was higher in the HIV-TB group than in the HIV group. Additionally, the administration of vitamin D supplements did not have obvious impact on CD4 count and viral load. Likewise, vitamin D had no effect on time to sputum smear conversion, time to culture conversion, relapse, 12-month morality, and TB score.

Vitamin D Level and Immune Modulation in Children with Recurrent Wheezing

INTRODUCTION AND AIM

A direct causal relationship between vitamin D (vit D) deficiency and recurrent wheezing has not been proven. The present study investigated the role of vit D in enhancing the risk of asthma or recurrent wheezing by modifying the intensity of the inflammatory process.

MATERIAL AND METHOD

Forty children with wheezing presenting at the emergency service and sixteen healthy control subjects were included in the study. Children with wheezing were either in the first episode (20) or with recurrent wheezing (20). Children with chronic diseases, and other conditions that present with acute wheezing or that might influence the vit D level, were excluded. Blood samples were taken at presentation and 3-6 months later, to evaluate the serum levels of total IgE, vit D, IL-10 and IL-31. Statistical analysis was performed using the SPSS 25 program, with a significance level of p < 0.05.

RESULTS AND CONCLUSION

The vit D level was lower in patients with recurrent wheezing compared with those with a single episode and with the control group, and this increased with time. IL-10 was significantly higher in children with wheezing than in the control group, with the highest values in those with an acute episode of wheezing. IL-31 was higher in children with recurrent wheezing than in those with a first episode only at the initial point, while at the final time point it was lower. Low levels of vit D appear to be detected more frequently in recurrent wheezing than in simple wheezing. Immune modulation, as measured by Th2 status reflected by IL-10 and IL-31 levels, appears to depend on the wheezing phenotype and on the general health status.

Vitamin D Improves Klebsiella-Induced Severe Pneumonia in Rats by Regulating Intestinal Microbiota

Background

In the context of progressively uncontrolled drug resistance of bacteria, the difficulty of treating Klebsiella (KP)-induced pneumonia increases. Searching for drugs other than antibiotics has become an urgent task. Vitamin D (VD), meanwhile, is shown to be capable of treating pneumonia. Therefore, we aimed to explore the effects and mechanisms of VD on KP-infected rats.

Methods

Male Sprague Dawley rats were divided into the Control, VD, KP and KP+VD groups. A rat pneumonia model was induced using an intratracheal drop of 2.4×108 CFU/mL KP. VD treatment was performed by gavage using 5 μg/kg. Subsequently, the survival of the rats was recorded, and the lungs, bronchoalveolar lavage fluid, and feces of the rats were collected 4 days after KP infection. Next, the water content of lung tissues was measured by the wet-to-dry weight ratio. Histopathological changes of lung tissues were observed by Hematoxylin and Eosin staining and the levels of inflammatory factors (TNF-α, IL-1β, MCP1) were detected using ELISA. The feces of rats in each group were also subjected to 16S rDNA gene analysis of intestinal microbiota.

Results

Compared with the KP group, the KP+VD group showed a significant increase in survival, a significant decrease in water content and bacterial counts in the lungs, a significant improvement in lung injury, and a significant decline in the levels of TNF-α, IL-1β, and MCP1. According to the 16S rDNA sequencing, VD altered the structure of the intestinal bacterial community in the KP-infected rats and made the species richness similar to that of healthy rats. Additionally, the abundance of Anaeroglobus was significantly increased in the KP+VD group.

Conclusion

VD modulates intestinal microbiota to increase the resistance of rats to pneumonia caused by Klebsiella infection.

Evaluation of Vitamin D Levels in Children With Liver Transplant

OBJECTIVES

Vitamin D deficiency is common in pediatric chronic liver disease despite oral replacement. We evaluated vitamin D deficiency before and after liver transplant and the relationship between posttransplant and pretransplant vitamin D deficiency and graft rejection.

MATERIALS AND METHODS

Pediatric recipients with chronic liver disease (N =138) were divided into 4 groups: cholestatic liver diseases, cirrhosis, metabolic disorders, and acute liver failure. Pretransplant and posttransplant vitamin D levels, liver function tests, Pediatric End-Stage Liver Disease scores, rejection activity index scores by graft liver biopsy, and posttransplant patient survival were recorded.

RESULTS

There were 62 (45%) female and 76 (55%) male participants (mean transplant age, 6.1 ± 5.6 years). Pretransplant mean available vitamin D of 90 patients was 25.2 ± 20.9 ng/mL, with 36 (40%) within reference range. Posttransplant level for 109 patients was 27.3 ± 18 ng/mL, with 64 (58.7%) within reference range. Pretransplant and posttransplant levels were available for 61 patients, and mean pretransplant levels were lower than posttransplant levels (23.7 ± 19.3 vs 28.3 ± 16.9 ng/mL; P = .01). Patients with cholestatic liver disease had lower pretransplant vitamin D levels (P = .04), which disappeared after transplant. Pretransplant vitamin D levels were positively correlated with serum albumin levels (r = 0.20) in all patients and negatively correlated with total/direct bilirubin (r = 0.29 and r = -0.30) in those with liver diseases and cirrhosis. No correlations were found between pretransplant vitamin D levels and Pediatric End-Stage Liver Disease scores, rejection activity index scores, and posttransplant mortality.

CONCLUSIONS

Vitamin D deficiency is prevalent in pediatric chronic liver disease before and after transplant, especially for cholestatic liver diseases. However, no association between vitamin D levels and liver graft rejection or patient survival was noted. We recommend close monitoring and individualized vitamin D supplementation before and after liver transplant.

Mini-Review on Vitamin D in Pediatric Population and its Role in Respiratory and Atopic Disorders

In recent years, our comprehension of the function of vitamin D has significantly evolved. The ubiquitous presence of the vitamin D receptor (Vitamin D Receptor- VDR) in the body has led to its redefinition from a steroidal hormone primarily involved in skeletal functions to a hormone with pleiotropic effects, exerting its influence on the circulatory, nervous, and immune systems. This has prompted investigations into its potential use in preventing and treating chronic metabolic disorders, cardiovascular diseases, infections, and allergic and autoimmune diseases. This comprehensive review explores the various aspects of vitamin D, including its sources, synthesis, functions, and its impact on different physiological systems. It delves into the epidemiology of vitamin D deficiency, highlighting its occurrence among various age demographics and geographic regions. The impact of vitamin D on the immune system is also explored, elucidating its immunomodulatory and anti-inflammatory properties, particularly in the context of respiratory infections. The review discusses emerging evidence concerning the potential advantages of vitamin D in respiratory diseases, pediatric asthma and atopic dermatitis. It also addresses vitamin D supplementation recommendations for various pediatric populations, including term and preterm infants. The growing concern regarding the global health impacts of insufficient vitamin D levels necessitates further research to bridge gaps in knowledge, particularly in enhancing screening, prevention, and approaches to address vitamin D deficiency from birth onwards. In summary, this comprehensive overview underscores the vital role of vitamin D, highlighting the significance of understanding its multifaceted functions and the need for tailored supplementation strategies, especially in vulnerable populations.

Proceedings of the 2023 Santa Fe Bone Symposium: Progress and Controversies in the Management of Patients with Skeletal Diseases

The Santa Fe Bone Symposium (SFBS) held its 23rd annual event on August 5-6, 2023, in Santa Fe, New Mexico, USA. Attendees participated in-person and remotely, representing many states and countries. The program included plenary presentations, panel discussions, satellite symposia, a Project ECHO workshop, and a session on healthcare policy and reimbursement for fracture liaison programs. A broad range of topics were addressed, including transitions of osteoporosis treatments over a lifetime; controversies in vitamin D; update on Official Positions of the International Society for Clinical Densitometry; spine surgery and bone health; clinical applications of bone turnover markers; basic bone biology for clinicians; premenopausal-, pregnancy-, and lactation-associated osteoporosis; cancer treatment induced bone loss in patients with breast cancer and prostate cancer; genetic testing for skeletal diseases; and an update on nutrition and bone health. There were also sessions on rare bone diseases, including managing patients with hypophosphatasia; treatment of X-linked hypophosphatemia; and assessment and treatment of patients with hypoparathyroidism. There were oral presentations of abstracts by endocrinology fellows selected from those who participated in the Santa Fe Fellows Workshop on Metabolic Bone Diseases, held the 2 days prior to the SFBS. These proceedings of the 2023 SFBS present the clinical highlights and insights generated from many formal and informal discussions in Santa Fe.

Latent TB Infection, Vitamin D Status and COVID-19 Severity in Mongolian Patients

We aimed to determine potential risk factors for COVID-19 severity including serum vitamin D levels and latent TB infection among Mongolian inpatients diagnosed with COVID-19, and to study the effects of disease complications and treatment outcomes. This study included patients admitted to the Mongolian National Center for Communicable Disease, a main referral center for infectious disease in Mongolia, with COVID-19 ascertained by a positive PCR test. Patients' demographic, clinical, and laboratory data were analyzed. Of the 270 patients enrolled, 125 (46%) had mild-to-moderate illness, 86 (32%) had severe illness, and 59 (22%) had critical illness. Ten (91%) of the 11 patients who had active TB were hospitalized with severe or critical COVID-19, suggesting that they had a higher risk of falling into the severe category (OR = 10.6 [1.2; 92.0] 95% CI). Severe vitamin D deficiency (25(OH)D < 10 ng/mL) was present in 32% of the patients, but was not significantly associated with the severity of illness (p = 0.65). Older age, being male, having active TB and/or COPD were associated with greater COVID-19 severity, whereas a history of COVID-19 vaccination and the presence of a BCG vaccination scar were protective in terms of disease severity.

Vitamin D and Its Association with H. pylori Prevalence and Eradication: A Comprehensive Review

Taking into account previous data that sustain a relationship between vitamin D deficiency and higher H. pylori infection positivity rates, this review aims to assess the influence of vitamin D deficiency and/or insufficiency upon the prevalence of H. pylori infection and its eradication success. Three major databases were searched for articles that analyzed a relationship between vitamin D status and H. pylori infection. The literature search retrieved a total of 37 reports, after the article selection process. Hypovitaminosis D emerged as a potential risk factor for H. pylori infection, given the higher prevalence of vitamin D deficiency and/or insufficiency among H. pylori-positive subjects. Furthermore, the same type of micronutrient deficiency has been directly linked to H. pylori eradication failure. An inverse linear relationship between vitamin D status and gastric cancer risk exists, but the additional involvement of H. pylori in this correlation is still in question. The potential benefit of oral supplements in enhancing the success of classical therapeutic regimens of H. pylori still requires future research. Future population-based studies from larger geographical areas are warranted to address this subject in more depth.

Assessment, treatment and prevention of vitamin D deficiency

Vitamin D deficiency is prevalent among various groups in the UK, and can result from insufficient sunlight exposure and dietary intake. There is a population-wide recommendation of 10 micrograms (400 international units) of vitamin D per day, with a daily supplement advised. However, supplement use is often suboptimal, compounding the risk of deficiency. Long-term vitamin D deficiency can cause rickets in children and osteomalacia or osteoporosis in adults. Therefore, it is important that nurses recognise which groups are at increased risk of vitamin D deficiency and understand how to assess people's vitamin D status. Nurses also need to be able to support the prevention and treatment of low vitamin D levels, which typically involves supplementation and lifestyle changes.

A Retrospective Analysis of Vitamin D Levels in Hospitalized COVID-19 Patients With Suspected Pulmonary Embolism

Introduction Despite using anti-coagulation therapy in hospitalized coronavirus disease 2019 (COVID-19) patients, they have high rates of pulmonary embolism (PE) and deep vein thrombosis (DVT). The main objective of this study was to evaluate the association between vitamin D deficiency and thrombotic events (defined as the occurrence of a new PE or DVT) in hospitalized COVID-19 patients. Materials and Methods This was a retrospective, cross-sectional study of 208 hospitalized COVID-19 patients who received a computed tomographic pulmonary angiography (CTPA) based on clinical suspicion of PE between January 1, 2020, and February 5, 2021. A <20 ng/mL serum vitamin D level was used to categorize vitamin D deficiency. Nonparametric tests and multivariate binary logistic regression were used to evaluate the association between serum vitamin D levels and clinical outcomes. Results The mean vitamin D level was 26.7±13.0 ng/mL (n=208), and approximately one-third of patients were vitamin D deficient (n=68, 32.7%). No association was found between vitamin D deficiency and the occurrence of thrombotic events. The incidence of PE was 19.1% in vitamin D deficient patients compared to 11.4% in vitamin D sufficient patients (p=0.13). Vitamin D deficiency was positively associated with ICU admission (OR 3.047, 95%CI 1.57-5.91, p=0.001) and mortality (OR 3.76, 95%CI 1.29-11.01, p=0.016). Conclusions This study found no association between vitamin D deficiency and the occurrence of a new PE or DVT in hospitalized COVID-19 patients. Patients with vitamin D deficiency were more likely to be admitted to the ICU and had increased overall mortality.

Difference in Levels of Vitamin D between Indoor and Outdoor Athletes: A Systematic Review and Meta-Analysis

Vitamin D, its importance in different processes taking place in the human body, the effects of abnormal levels of this hormone, either too low or too high, and the need for supplementation have been extensively researched thus far. Variances in exposure to sunlight can cause vitamin D levels to fluctuate. Indoor activity can be a factor for these fluctuations and can lead to a decrease in vitamin D levels. We conducted a systematic review and meta-analysis aiming to identify whether indoor compared to outdoor training has a significant influence on vitamin D levels; we also performed subgroup analyses and multivariate meta-regression. The type of training has an impact on vitamin D levels that is influenced by multiple cofounders. In a subgroup analysis not considering cofounders, the mean serum vitamin D was 3.73 ng/mL higher in outdoor athletes, a difference which barely fails to achieve significance (p = 0.052, a total sample size of 5150). The indoor-outdoor difference is only significant (clinically and statistically) when considering studies performed exclusively on Asian athletes (a mean difference of 9.85 ng/mL, p < 0.01, and a total sample size of 303). When performing the analyses within each season, no significant differences are observed between indoor and outdoor athletes. To control for multiple cofounders (the season, latitude, and Asian/Caucasian race) simultaneously, we constructed a multivariate meta-regression model, which estimated a serum vitamin D concentration lower by 4.446 ng/mL in indoor athletes. While a multivariate model suggests that outdoor training is associated with slightly higher vitamin D concentrations when controlling for the season, latitude, and Asian/Caucasian race, the type of training has a numerically and clinically small impact. This suggests that vitamin D levels and the need for supplementation should not be decided based on training type alone.

Vitamin D and COVID-19: where are we now?

The pandemic caused by the SARS-CoV-2 virus has triggered great interest in the search for the pathophysiological mechanisms of COVID-19 and its associated hyperinflammatory state. The presence of prognostic factors such as diabetes, cardiovascular disease, hypertension, obesity, and age influence the expression of the disease's clinical severity. Other elements, such as 25-hydroxyvitamin D (25(OH)D3) concentrations, are currently being studied. Various studies, mostly observational, have sought to demonstrate whether there is truly a relationship between 25(OH)D3 levels and the acquisition and/or severity of the disease. The objective of this study was to carry out a review of the current data that associate vitamin D status with the acquisition, evolution, and/or severity of infection by the SARS-CoV-2 virus and to assess whether prevention through vitamin D supplementation can prevent infection and/or improve the evolution once acquired. Vitamin D system has an immunomodulatory function and plays a significant role in various bacterial and viral infections. The immune function of vitamin D is explained in part by the presence of its receptor (VDR) and its activating enzyme 25-hydroxyvitamin D-1alpha-hydroxylase (CYP27B1) in immune cells. The vitamin D, VDR, and Retinoid X Receptor complex allows the transcription of genes with antimicrobial activities, such as cathelicidins and defensins. COVID-19 characteristically presents a marked hyperimmune state, with the release of proinflammatory cytokines such as IL-6, TNF-α, and IL-1β. Thus, there are biological factors linking vitamin D to the cytokine storm, which can herald some of the most severe consequences of COVID-19, such as acute respiratory distress syndrome. Hypovitaminosis D is widespread worldwide, so the prevention of COVID-19 through vitamin D supplementation is being considered as a possible therapeutic strategy easy to implement. However, more-quality studies and well-designed randomized clinical trials are needed to address this relevant question.

A Phase 1 Study of Oral Vitamin D3 in Boys and Young Men With X-Linked Adrenoleukodystrophy

Background and Objectives

There are no therapies for preventing cerebral demyelination in X-linked adrenoleukodystrophy (ALD). Higher plasma vitamin D levels have been linked to lower risk of inflammatory brain lesions. We assessed the safety and pharmacokinetics of oral vitamin D dosing regimens in boys and young men with ALD.

Methods

In this open-label, multicenter, phase 1 study, we recruited boys and young men with ALD without brain lesions to a 12-month study of daily oral vitamin D3 supplementation. Our primary outcome was attainment of plasma 25-hydroxyvitamin D levels in target range (40-80 ng/mL) at 6 and 12 months. Secondary outcomes included safety and glutathione levels in the brain, measured with magnetic resonance spectroscopy, and blood, measured via mass spectrometry. Participants were initially assigned to a fixed dosing regimen starting at 2,000 IU daily, regardless of weight. After a midstudy safety assessment, we modified the dosing regimen, so all subsequent participants were assigned to a weight-stratified dosing regimen starting as low as 1,000 IU daily.

Results

Between October 2016 and June 2019, we enrolled 21 participants (n = 12, fixed-dose regimen; n = 9, weight-stratified regimen) with a median age of 6.7 years (range: 1.9-22 years) and median weight of 20 kg (range: 11.7-85.5 kg). The number of participants achieving target vitamin D levels was similar in both groups at 6 months (fixed dose: 92%; weight stratified: 78%) and 12 months (fixed dose: 67%; weight stratified: 67%). Among the 12 participants in the fixed-dose regimen, half had asymptomatic elevations in either urine calcium:creatinine or plasma 25-hydroxyvitamin D; no laboratory deviations occurred with the weight-stratified regimen. Glutathione levels in the brain, but not the blood, increased significantly between baseline and 12 months.

Discussion

Our vitamin D dosing regimens were well tolerated and achieved target 25-hydroxyvitamin D levels in most participants. Brain glutathione levels warrant further study as a biomarker for vitamin D and ALD.

Classification of Evidence

This study provides Class IV evidence that fixed or weight-stratified vitamin D supplementation achieved target levels of 25-hydroxyvitamin D in boys and young men with X-ALD without brain lesions.

The biological responses of vitamin K2: A comprehensive review

Vitamin K1 (VitK1) and Vitamin K2 (VitK2), two important naturally occurring micronutrients in the VitK family, found, respectively, in green leafy plants and algae (VitK1) and animal and fermented foods (VitK2). The present review explores the multiple biological functions of VitK2 from recently published in vitro and in vivo studies, including promotion of osteogenesis, prevention of calcification, relief of menopausal symptoms, enhancement of mitochondrial energy release, hepato- and neuro-protective effects, and possible use in treatment of coronavirus disease. The mechanisms of action associated with these biological effects are also explored. Overall, the findings presented here suggest that VitK, especially VitK2, is an important nutrient family for the normal functioning of human health. It acts on almost all major body systems and directly or indirectly participates in and regulates hundreds of physiological or pathological processes. However, as biological and clinical data are still inconsistent and conflicting, more in-depth investigations are warranted to elucidate its potential as a therapeutic strategy to prevent and treat a range of disease conditions.

Is the vitamin D status of patients with COVID-19 associated with reduced mortality? A systematic review and meta-analysis

To conduct a systematic review and meta-analysis of studies assessing the association between serum vitamin D status and mortality in patients with COVID- 19. We searched PubMed and Embase for studies addressing the association of serum vitamin D levels and COVID-19 mortality published until April 24, 2022. Risk ratios (RRs) and 95% confidence interval (CIs) were pooled using fixed or random effects models. The risk of bias was assessed using the Newcastle-Ottawa Scale. The meta-analysis included 21 studies that measured serum vitamin D levels close to the date of admission, of which 2 were case-control and 19 were cohort studies. Vitamin D deficiency was associated with COVID-19 mortality in the overall analysis but not when the analysis was adjusted to vitamin D cutoff levels < 10 or < 12 ng/mL (RR 1.60, 95% CI 0.93-2.27, I2 60.2%). Similarly, analyses including only studies that adjusted measures of effect for confounders showed no association between vitamin D status and death. However, when the analysis included studies without adjustments for confounding factors, the RR was 1.51 (95% CI 1.28-1.74, I2 0.0%), suggesting that confounders may have led to many observational studies incorrectly estimating the association between vitamin D status and mortality in patients with COVID-19. Deficient vitamin D levels were not associated with increased mortality rate in patients with COVID-19 when the analysis included studies with adjustments for confounders. Randomized clinical trials are needed to assess this association.

Vitamin D deficiency and driveline infection in patients with a left ventricular assist device implant

Driveline infection is a frequent complication in recipients of durable left ventricular assist devices (LVAD), but its cause is largely unclear. Since vitamin D supplementation can reduce the risk of infections, we aimed at investigating the association of vitamin D deficiency with driveline infection. In 154 patients with continuous flow LVAD implants, we assessed 2-year risk of driveline infection according to vitamin D status (circulating 25-hydroxyvitamin D < 25 nmol/L or ⩾25 nmol/L). Of the study cohort, 34% (n = 53) had 25-hydroxyvitamin D concentrations <25 nmol/L. Kaplan-Meir estimates of 2-year freedom from driveline infection were in the vitamin D deficient and vitamin D non-deficient groups 49.7% and 74.2%, respectively (p = 0.017). Covariate-adjusted hazard ratio of driveline infection for the vitamin D deficient versus non-deficient group was 2.51 [95% CI: 1.11-5.69; p = 0.028). Circulating concentrations of endocrine regulators of calcium and phosphorus metabolism such as parathyroid hormone, 1,25-dihydroxyvitamin D, and fibroblast growth factor-23 were not significantly associated with the risk of driveline infection (p-values > 0.15). In total, our data indicate that in LVAD recipients deficient vitamin D status is a predictor of driveline infection, but future studies are needed to investigate whether these associations are causal.

Non-pharmacological remedies for the common cold

Acute rhinopharyngitis, usually called common cold, is a widespread disease, mainly in childhood and adolescence. The use of common cold relievers is, therefore, prevalent as documented by the market data. A well-established tradition considers natural remedies an effective and safe way to relieve the common cold. Hundreds of products for treating the common cold contain non-pharmacological components. Nevertheless, a few studies investigated the role of non-pharmacologic remedies for the common cold. The current study reported the most common non-pharmacological remedies for the common cold, including herbal medicines and other substances. As ancient people used traditional herbs to treat and prevent the common cold, various herbs are widely used to clear viral infections. The herbal agents include polyphenols, flavonoids, saponins, glucosides, and alkaloids. Moreover, other non-pharmacological agents are widely used in real-life. Many multi- or monocomponent dietary supplements or medical devices contain these substances and are available in the market as tablets, syrups, drops, nasal or oral sprays, and nebulization solutions. Many products are available in the market. However, there is some evidence only for some substances. Consequently, further rigorous studies should confirm natural products' efficacy and safety to relieve the common cold.

Vitamin D in patients with COVID-19: is there a room for it?

Vitamin-D receptors are found in a variety of cells with the potential to regulate many cellular functions. Higher COVID-19 severity has been reported in individuals, which are known to have lower vitamin-D levels. The relation between vitamin-D and COVID-19 has been analysed with a number of studies but only few met high standards. Studies revealed discordant findings. There is no data from interventional trials clearly indicating that vitamin-D supplementation may prevent against COVID-19. An increasing number of observational studies put forward the preventive feature of adequate vitamin-D status for COVID-19 mortality. Yet, there are again conflicting findings. This narrative review summarizes the current evidence and provides a practical advice to lessen the impact of COVID-19 by ensuring recommended vitamin-D intakes. This approach would not be harmful, but potentially useful. Vitamin-D is safe especially if it does not exceed the upper-tolerable-limit. Daily doses are recommended over the weekly or monthly higher doses. Mega-doses are not recommended because of its potential to lead adverse events. The target level of vitamin-D is proposed above 30 ng/mL in majority of the studies. Nonetheless, one should consider that the benefit is foreseen to be small, and some time (months) may be needed for such effect.

Vitamin D3 and COVID-19 Outcomes: An Umbrella Review of Systematic Reviews and Meta-Analyses

BACKGROUND

The immune system (innate and adaptive) is influenced by vitamin D3, which affects gene expression and inflammatory pathways. An umbrella review was conducted to evaluate the power and accuracy of data connecting vitamin D3 to the outcomes of COVID-19 infection and to appraise the proof provided by published meta-analyses.

METHODS

MEDLINE, Embase, and the Cochrane Library were searched from database inception to 31 May 2022. Meta-analyses of prospective or retrospective observational studies and randomized trials were included. Evidence of association was graded according to the established criteria: strong, highly suggestive, suggestive, weak, or not significant.

RESULTS

From 74 publications, 27 meta-analyses described five associations between vitamin D3 levels and supplementation and COVID-19 outcomes. Low levels of vitamin D3 were significantly associated with severity (highly suggestive evidence; OR = 1.97 [95% CI, 1.55-2.51], p < 0.01; I² = 77%, p < 0.01) and mortality risk due to COVID-19 disease (OR = 1.83 [95% CI, 1.55-2.16], p < 0.01; I² = 50%, p < 0.01). Vitamin D3 supplementation, after a diagnosis of COVID-19 infection, was associated with significantly reduced infection severity (e.g., ICU admission) and mortality.

CONCLUSIONS

This umbrella review of the available evidence suggests that insufficient vitamin D3 may increase COVID-19 infection risk, severity, and mortality, in addition to showing a highly suggestive association between vitamin D3 supplementation and reduced severity and mortality among infected patients.

Vitamin D-A prominent immunomodulator to prevent COVID-19 infection

COVID-19 remains a life-threatening infectious disease worldwide. Several bio-active agents have been tested and evaluated in an effort to contain this disease. Unfortunately, none of the therapies have been successful, owing to their safety concerns and the presence of various adverse effects. Various countries have developed vaccines as a preventive measure; however, they have not been widely accepted as effective strategies. The virus has proven to be exceedingly contagious and lethal, so finding an effective treatment strategy has been a top priority in medical research. The significance of vitamin D in influencing many components of the innate and adaptive immune systems is examined in this study. This review aims to summarize the research on the use of vitamin D for COVID-19 treatment and prevention. Vitamin D supplementation has now become an efficient option to boost the immune response for all ages in preventing the spread of infection. Vitamin D is an immunomodulator that treats infected lung tissue by improving innate and adaptive immune responses and downregulating the inflammatory cascades. The preventive action exerted by vitamin D supplementation (at a specific dose) has been accepted by several observational research investigations and clinical trials on the avoidance of viral and acute respiratory dysfunctions. To assess the existing consensus about vitamin D supplementation as a strategy to treat and prevent the development and progression of COVID-19 disease, this review intends to synthesize the evidence around vitamin D in relation to COVID-19 infection.

Strong Association between Vitamin D Receptor Gene and Severe Acute Respiratory Syndrome coronavirus 2 Infectious Variants

A coronavirus disease 2019 (COVID-19) disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has created significant concern since December 2019 worldwide. The virus is known to be highly transmissible. Heterogenic clinical features even vary more among SARS-CoV-2 variants from asymptomatic forms to severe symptoms. Previous studies revealed an association between COVID-19 and vitamin D deficiency resulting from its low levels in COVID-19 patients. To our knowledge, there is no scientific investigation that evaluates the direct association between SARS-CoV-2 variants of concern and vitamin D receptor ( VDR ) gene markers in Cyprus. Thus, the present study aimed to identify the putative impact of VDR gene polymorphisms on SARS-CoV-2 infection among different variants. The nasopharyngeal swabs were taken from a total number of 600 patients who were admitted to Near East University Hospital COVID-19 Polymerase Chain Reaction (PCR) Diagnosis Laboratory for routine SARS-CoV-2 real-time quantitative reverse transcription PCR (RT-qPCR) test. The RT-qPCR negative resulting samples were taken as control samples ( n  = 300). On the contrary, the case group consisted of patients who were SARS-CoV-2 RT-qPCR positive, infected with either SARS-CoV-2 Alpha ( n  = 100), Delta ( n  = 100), or Omicron ( n  = 100) variants. Two VDR gene polymorphisms, Taq I-rs731236 T > C and Fok I-rs10735810 C > T, were genotyped by polymerase chain reaction-restriction fragment length polymorphism. The mean age of the COVID-19 patient's ± standard deviation was 46.12 ± 12.36 and 45.25 ± 12.71 years old for the control group ( p  > 0.05). The gender distribution of the patient group was 48.3% female and 51.7% male and for the control group 43% female and 57% male ( p  > 0.05). Significant differences were observed in genotype frequencies of FokI and TaqI variants between SARS-CoV-2 patients compared to the control group ( p  < 0.005). Furthermore, the risk alleles, FokI T allele and TaqI C, were found to be statistically significant (odds ratio [OR] = 1.80, 95% confidence interval [CI] = 1.42-2.29, OR = 1.62, 95% CI = 1.27-2.05, respectively) in COVID-19 patients. The highest number of patients with wild-type genotype was found in the control group, which is 52.9% compared with 17.5% in the case group. Moreover, most of the COVID-19 patients had heterozygous/homozygous genotypes, reaching 82.5%, while 47.1% of the control group patients had heterozygous/homozygous genotypes. Our results suggested that patients with FokI and TaqI polymorphisms might tend to be more susceptible to getting infected with SARS-CoV-2. Overall, findings from this study provided evidence regarding vitamin D supplements recommendation in individuals with vitamin D deficiency/insufficiency in the peri- or post-COVID-19 pandemic.

Vitamin D supplementation and lower respiratory tract infection in infants: a nested case-control study

PURPOSE

To assess the association between vitamin D (VD) supplementation and the risk of lower respiratory tract infection (LRTI) among infants.

METHODS

This is a nested case-control study from an ongoing prospective birth cohort in Wuhan from 2013. Cases were subjects free of neonatal pneumonia but later developed LRTI during infancy, who were matched with five randomly selected controls by infant sex, birth year, and birth season. We included 190 cases and 950 controls in the final analysis. The primary outcome was the first LRTI incident and the exposure was VD supplementation from birth to the index endpoint. The association between VD supplementation and LRTI risk was assessed using the Cox proportional-hazards regression model.

RESULTS

Infants taking supplements had a 59% relative reduction in the hazard ratio of LRTI (HR = 0.41; 95% CI 0.26, 0.64) compared to those not supplemented. There was a linear relationship between LRTI risk and VD supplementation within range of 0-603 IU/day: for each 100 IU per day increment in VD supplementation, infants experienced a 21% lower risk of developing LRTI (adjusted HR: 0.79; 95% CI 0.71, 0.89). The linear relationship was stably observed in the sensitivity analyses as well.

CONCLUSIONS

VD supplementation was associated with the reduced risk of LRTI throughout infancy, and the optimal supplementation dose for infants may be beyond the current recommendation.

Differential Gene Expression Induced by Different TLR Agonists in A549 Lung Epithelial Cells Is Modulated by CRISPR Activation of TLR10

Toll-like receptor 10 (TLR10) is the only member of the TLR family whose function and ligand have not been clearly described. Literature reports on its function are contradictory and suggest a possible immunomodulatory role that depends on the cell type, the pathogen, and the level of TLR10 expression. To investigate the regulatory role of TLR10 in A549 lung epithelial cells, we overexpressed TLR10 using CRISPRa technology and examined the differential expression of various genes involved in TLR signaling activated by different TLR ligands, namely dsRNA, LPS, and Pam3Cys. The expression of proinflammatory cytokines, such as IL1β, IFNβ, TNFα, IL8, CXCL10, and CCL20, decreased in the challenged cells overexpressing TLR10, whereas the expression of the anti-inflammatory cytokine IL10 and the antimicrobial peptide hβD-2 increased. For several of the regulated inflammatory markers, we were able to show the change in gene expression was translated to the protein level. It appears that TLR10 can function as an anti-inflammatory in A549 cells, depending on its expression level and that the mode of action may be virulence factor-specific. The potential suppression of inflammation by regulating expression of TLR10 in lung epithelial cells may allow the development of new approaches to balance an inflammatory response and prevent extensive tissue damage in respiratory diseases.

Behavioral and Dietary Habits That Could Influence Both COVID-19 and Non-Communicable Civilization Disease Prevention-What Have We Learned Up to Now?

The massive expansion of the new coronavirus SARS-CoV-2 has urged countries to introduce lockdowns and set restrictive actions worldwide. The focus of the studies was to determine how COVID-19 induces damage to the lungs in order to find an alternative or adjuvant therapy that could lead to preventing COVID-19 or at least ameliorating it. This paper aims to survey the literature and provide new insights into behavioral and dietary habits that could influence the prevention of COVID-19. Maintaining an adequate mental health status, sleep, and taking moderate exercise are often disrupted in the conditions of lockdown and are followed by weakened immunity. Mediterranean and vegetarian diets are superior to other eating patterns in terms of immunity boosting and fighting COVID-19. Our study showed how adequate hydration, green tea intake, and supplementation with vitamins D, C, and E can increase our chances of avoiding the infection and even help us sleep better. Another focus of the research was on determining what level of hygiene really increases one's chances of not contracting SARS-CoV-2, but this seems a little counter-intuitive at first. Since an immunocompromised state is a familiar predisposing factor for all contagious diseases, maintaining healthy behavioral and dietary habits could be a crucial step in boosting immunity and preventing COVID-19.

Effects on Serum Inflammatory Cytokines of Cholecalciferol Supplementation in Healthy Subjects with Vitamin D Deficiency

The effects of different cholecalciferol supplementation regimens on serum inflammatory cytokines in healthy subjects with vitamin D deficiency are still lacking. This is a single-center, open-label, randomized, parallel group study involving healthy subjects deficient in vitamin D (baseline 25OHD < 20 ng/mL) receiving oral cholecalciferol with three different dosing regimens: Group A: 10,000 IU/day for 8 weeks followed by 1000 IU/day for 4 weeks; Group B: 50,000 IU/week for 12 weeks and Group C: 100,000 IU every other week for 12 weeks. IL-17A, IL-6, IL-8, IL-10, IL-23 and TNFα were measured at baseline and at week 4, 8, 12, and 16. 75 healthy subjects were enrolled (58.7% female), with an average age of 34.1 ± 10.2 years. No statistical differences were observed among groups at baseline for either IL-6, IL-17A, IL-23, IL-8 or IL-10 at any time point; TNFα was indetectable. Concerning the whole sample, the time trend analysis showed a statistically significant linear trend for decreasing values over the treatment period for IL-6 (p = 0.016) and IL-17A (p = 0.006), while no significant time trends were observed for the other teste cytokines. No significant differences were found in the serum concentrations of the tested cytokines between week 12 and week 16. In young healthy individuals deficient in vitamin D, cholecalciferol administration showed a decrease in the serum IL-6 and IL-17A concentrations, without marked differences using the three regimens.

Risk Factors Affecting Development and Persistence of Preschool Wheezing: Consensus Document of the Emilia-Romagna Asthma (ERA) Study Group

Wheezing at preschool age (i.e., before the age of six) is common, occurring in about 30% of children before the age of three. In terms of health care burden, preschool children with wheeze show double the rate of access to the emergency department and five times the rate of hospital admissions compared with school-age asthmatics. The consensus document aims to analyse the underlying mechanisms involved in the pathogenesis of preschool wheezing and define the risk factors (i.e., allergy, atopy, infection, bronchiolitis, genetics, indoor and outdoor pollution, tobacco smoke exposure, obesity, prematurity) and the protective factors (i.e., probiotics, breastfeeding, vitamin D, influenza vaccination, non-specific immunomodulators) associated with the development of the disease in the young child. A multidisciplinary panel of experts from the Emilia-Romagna Region, Italy, addressed twelve key questions regarding managing preschool wheezing. Clinical questions have been formulated by the expert panel using the PICO format (Patients, Intervention, Comparison, Outcomes). Systematic reviews have been conducted on PubMed to answer these specific questions and formulate recommendations. The GRADE approach has been used for each selected paper to assess the quality of the evidence and the degree of recommendations. Based on a panel of experts and extensive updated literature, this consensus document provides insight into the pathogenesis, risk and protective factors associated with the development and persistence of preschool wheezing. Undoubtedly, more research is needed to improve our understanding of the disease and confirm the associations between certain factors and the risk of wheezing in early life. In addition, preventive strategies must be promoted to avoid children's exposure to risk factors that may permanently affect respiratory health.

Influence of vitamin D supplementation on immune function of healthy aging people: A pilot randomized controlled trial

OBJECTIVES

This study aims to investigate the influence of vitamin D supplementation on immune function of healthy older adults.

MATERIALS AND METHODS

Designed as a randomized controlled trial, 21 participants (55-85 years) completed the study during May-November 2018 in Coventry, England. The participants were randomized into vitamin D or the control group, stratified by age, gender and body mass index. The vitamin D group (n = 12) took vitamin D3 tablets of 1,000 IU/day for 12 weeks plus vitamin D education leaflet, while the control group (n = 9) were only provided with the leaflet. At baseline, 6 and 12 weeks, plasma 25(OH)D levels and immunological and metabolic parameters including phagocytic activity of granulocytes and monocytes, tumor necrosis factor, interleukin 6, lymphocyte subsets and fasting blood glucose and lipid were measured. Dietary vitamin D intake was analyzed at baseline and week 12. Data were presented as mean ± SD. Two-way repeated measures ANOVA and independent t-test were used to analyze the data.

RESULTS

At baseline, 42.9% of the participants were vitamin D deficiency (25(OH)D < 25 nmol/L), only 10% achieved a level of 25(OH)D > 50 nmol/L. Overweight/obese participants (n = 9) had significantly lower mean plasma 25(OH)D concentration (22.3 ± 8.7 nmol/L) than normal weight participants (48.1 ± 34.3 nmol/L) (P = 0.043). There was a significant increase in plasma 25(OH)D concentration in vitamin D group compared with that in control group (P = 0.002) during the intervention period. The plasma 25(OH)D concentration in vitamin D group was increased at 6 weeks (from 38.4 ± 37.0 nmol/L at baseline to 51.0 ± 38.2 nmol/L) with little change observed between 6 and 12 weeks (51.8 ± 36.4 nmol/L). The plasma creatinine concentration in vitamin D group was significantly decreased compared with the control group (P = 0.036) (79.8 ± 7.0 μmol/L at baseline vs 75.1 ± 5.4 μmol/L at week 12). No significant effect of vitamin D supplementation was determined on immunological parameters.

CONCLUSION

Vitamin D deficiency is common among the aging population in the UK even during the summertime. Vitamin D supplementation at 1,000 IU/day for 12 weeks significantly increased plasma 25(OH)D concentration but showed no effect on metabolic and immunological parameters except decreased plasma creatinine.

Visualizing the knowledge domains and research trends of childhood asthma: A scientometric analysis with CiteSpace

Background

Asthma is one of the most common chronic diseases in children globally. In recent decades, advances have been made in understanding the mechanism, diagnosis, treatment and management for childhood asthma, but few studies have explored its knowledge structure and future interests comprehensively.

Objective

This scientometric study aims to understand the research status and emerging trends of childhood asthma.

Methods

CiteSpace (version 5.8.R3) was used to demonstrate national and institutional collaborations in childhood asthma, analyze research subjects and journal distribution, review research keywords and their clusters, as well as detect research bursts.

Results

A total of 14,340 publications related to childhood asthma were extracted from Web of Science (core database) during January 2011 to December 2021. The results showed that academic activities of childhood asthma had increased steadily in the last decade. Most of the research was conducted by developed countries while China, as a developing country, was also actively engaged in this field. In addition to subjects of allergy and immunology, both public health aspects and ecological environmental impacts on the disease were emphasized recently in this research field. Keywords clustering analysis indicated that research on asthma management and atopy was constantly updated and became the two major research focuses recently, as a significant shift in research hotspots from etiology and diagnosis to atopic march and asthma management was identified. Subgroup analysis for childhood asthma management and atopy suggested that caregiver- or physician-based education and interventions were emerging directions for asthma management, and that asthma should be carefully studied in the context of atopy, together with other allergic diseases.

Conclusions

This study presented a comprehensive and systematic overview of the research status of childhood asthma, provided clues to future research directions, and highlighted two significant research trends of asthma management and atopy in this field.

Host-directed therapies in pulmonary tuberculosis: Updates on anti-inflammatory drugs

Tuberculosis (TB) is a lethal disease and remains one of the top ten causes of mortality by an infectious disease worldwide. It can also result in significant morbidity related to persistent inflammation and tissue damage. Pulmonary TB treatment depends on the prolonged use of multiple drugs ranging from 6 months for drug-susceptible TB to 6-20 months in cases of multi-drug resistant disease, with limited patient tolerance resulting from side effects. Treatment success rates remain low and thus represent a barrier to TB control. Adjunct host-directed therapy (HDT) is an emerging strategy in TB treatment that aims to target the host immune response to Mycobacterium tuberculosis in addition to antimycobacterial drugs. Combined multi-drug treatment with HDT could potentially result in more effective therapies by shortening treatment duration, improving cure success rates and reducing residual tissue damage. This review explores the rationale and challenges to the development and implementation of HDTs through a succinct report of the medications that have completed or are currently being evaluated in ongoing clinical trials.

Administration of vitamin D and its metabolites in critically ill adult patients: an updated systematic review with meta-analysis of randomized controlled trials

Background

The clinical significance of vitamin D administration in critically ill patients remains inconclusive. The purpose of this systematic review with meta-analysis was to investigate the effect of vitamin D and its metabolites on major clinical outcomes in critically ill patients, including a subgroup analysis based on vitamin D status and route of vitamin D administration.

Methods

Major databases were searched through February 9, 2022. Randomized controlled trials of adult critically ill patients with an intervention group receiving vitamin D or its metabolites were included. Random-effect meta-analyses were performed to estimate the pooled risk ratio (dichotomized outcomes) or mean difference (continuous outcomes). Risk of bias assessment included the Cochrane tool for assessing risk of bias in randomized trials.

Results

Sixteen randomized clinical trials with 2449 patients were included. Vitamin D administration was associated with lower overall mortality (16 studies: risk ratio 0.78, 95% confidence interval 0.62–0.97, p = 0.03; I² = 30%), reduced intensive care unit length of stay (12 studies: mean difference − 3.13 days, 95% CI − 5.36 to − 0.89, n = 1250, p = 0.006; I² = 70%), and shorter duration of mechanical ventilation (9 studies: mean difference − 5.07 days, 95% CI − 7.42 to − 2.73, n = 572, p < 0.0001; I² = 54%). Parenteral administration was associated with a greater effect on overall mortality than enteral administration (test of subgroup differences, p = 0.04), whereas studies of parenteral subgroups had lower quality. There were no subgroup differences based on baseline vitamin D levels.

Conclusions

Vitamin D supplementation in critically ill patients may reduce mortality. Parenteral administration might be associated with a greater impact on mortality. Heterogeneity and assessed certainty among the studies limits the generalizability of the results.

Trial registration: PROSPERO international prospective database of systematic reviews (CRD42021256939—05 July 2021).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04139-1.

Reply to Chambers, P. Comment on "Huțanu et al. Low Serum Vitamin D in COVID-19 Patients Is Not Related to Inflammatory Markers and Patients' Outcomes-A Single-Center Experience and a Brief Review of the Literature. Nutrients 2022, 14, 1998"

We thank Patrick Chambers for his interest [...].

Vitamin D and Multiple Health Outcomes: An Umbrella Review of Observational Studies, Randomized Controlled Trials, and Mendelian Randomization Studies

Observational studies, randomized controlled trials (RCTs), and Mendelian randomization (MR) studies have yielded inconsistent results on the associations of vitamin D concentrations with multiple health outcomes. In the present umbrella review we aimed to evaluate the effects of low vitamin D concentrations and vitamin D supplementation on multiple health outcomes. We summarized current evidence obtained from meta-analyses of observational studies that examined associations between vitamin D concentrations and multiple health outcomes, meta-analyses of RCTs that investigated the effect of vitamin D supplementation on multiple health outcomes, and MR studies that explored the causal associations of vitamin D concentrations with various diseases (international prospective register of systematic reviews PROSPERO registration number CRD42018091434). A total of 296 meta-analyses of observational studies comprising 111 unique outcomes, 139 meta-analyses of RCTs comprising 46 unique outcomes, and 73 MR studies comprising 43 unique outcomes were included in the present umbrella review. Twenty-eight disease outcomes were identified by both meta-analyses of observational studies and MR studies. Seventeen of these reported disease outcomes had consistent results, demonstrating that lower concentrations of vitamin D were associated with a higher risk for all-cause mortality, Alzheimer's disease, hypertension, schizophrenia, and type 2 diabetes. The combinations of consistent evidence obtained by meta-analyses of observational studies and MR studies together with meta-analyses of RCTs showed that vitamin D supplementation was associated with a decreased risk for all-cause mortality but not associated with the risk for Alzheimer's disease, hypertension, schizophrenia, or type 2 diabetes. The results indicated that vitamin D supplementation is a promising strategy with long-term preventive effects on multiple chronic diseases and thus has the potential to decrease all-cause mortality. However, the current vitamin D supplementation strategy might not be an efficient intervention approach for these diseases, suggesting that new strategies are highly needed to improve the intervention outcomes.

Vitamins C and D and COVID-19 Susceptibility, Severity and Progression: An Evidence Based Systematic Review

Background and Objectives: Starting in early December 2019, the novel Coronavirus Disease (COVID-19) from infection with COVID-19 has caused a global pandemic. Many aspects of its pathogenesis and related clinical consequences are still unclear. Early diagnosis and dynamic monitoring of prognostic factors are essential to improve the ability to manage COVID-19 infection. This study aimed to provide an account of the role played by vitamins C and D on the onset, progression and severity of COVID-19. Clinical features and infection-related risk factors are also briefly discussed. Material and Methods: In March 2022, the main online databases were accessed. All the articles that investigate the possible role of vitamins C and D on COVID-19 susceptibility, severity and progression were considered. Results: The current evidence on vitamin C and D supplementation in patients with COVID-19 infection is inconsistent and controversial. In some studies, vitamins were used as coadjuvant of a formal experimental therapy, while in others as main treatment. Ethnicity and hospital setting (inpatient/outpatient) were also variable. Moreover, there was no consensus between studies in administration protocol: high heterogeneity in dosage, administration, and duration of the treatment were evident. Finally, some studies administered vitamins pre- and/or during COVID infection, in patients with different risk factors and infection severity. Conclusions: While waiting to develop a targeted, safe and effective therapy, it is important to investigate individual predisposition and proper disease management. Concluding, available data on the use of nutraceuticals in COVID-19 are inconsistent. However, there is a lack of evidence-based guidelines which recommend vitamin C and D supplementation in patients with COVID-19, and results from high quality randomised controlled trials (RCTs) are inconsistent. Current investigations so far are mostly observational, and include a relatively small sample size which can lead to biased results. Large-scale multicentre studies are therefore needed.

A Meta-Analysis on Vitamin D Supplementation and Asthma Treatment

Background

Vitamin D, as an immunomodulator, may be related to the therapeutic effect of asthma patients, but the research in this area is still controversial. The aim of this meta-analysis was to analyze the role of vitamin D supplementation in the treatment of asthma patients.

Materials and Methods

Randomized Controlled Trials (RCTs) of vitamin D supplementation in asthma were searched in PubMed, EMBASE, and the Cochrane library. Primary outcomes were forced expiratory volume in one second (FEV1), asthma exacerbations, Asthma Control Test scores (ACT scores), and fractional exhaled nitric oxide (FENO).

Results

A total of 10 RCTs were included, including 1,349 patients. Vitamin D supplementation didn't affect the ACT scores (SMD = 0.04, 95% CI = -0.13 to 0.21, P = 0.87), FEV1 (SMD = 0.04, 95% CI = -0.35 to 0.43, P < 0.01) and FENO (SMD = -0.01, 95% CI = -0.22 to 0.20, P = 0.27), but reduced the rate of asthma exacerbations (RR = 0.69, 95% CI = 0.41 to 0.88, P < 0.01), especially in subgroups of children (RR = 0.46, 95% CI = 0.30 to 0.70, P = 0.83) and follow up time less than 6 months (RR = 0.45, 95% CI = 0.32 to 0.63, P = 0.95). Additionally, though there was only one study included in the subgroup, it significantly enhanced FEV1 at the last visit for patients whose FEV1 baseline value was less than 70% (SMD = 0.94, 95% CI = 0.47 to 1.41).

Conclusion

Vitamin D supplementation can reduce asthma exacerbations, especially in children, and within 6 months of follow up time. In addition, vitamin D has a positive effect on improving FEV1 of patients whose FEV1 baseline value is less than 70%, but more RCTs are still needed to support this conclusion.

Systematic Review Registration

[https://inplasy.com], identifier [10.37766/inplasy20 22.6.0049].

Immunomodulatory Effects of Vitamin D and Prevention of Respiratory Tract Infections and COVID-19

Little is known about potential protective factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), referred to as COVID-19. Suboptimal vitamin D status is a risk factor for immune dysfunction, respiratory tract infections (RTIs), and viral infections. Supplementation of vitamin D (2000-4000 IU) has decreased incidence and complications from RTIs, respiratory distress syndrome, and pneumonia and may be beneficial in high-risk populations. Given the possible link between low vitamin D status and RTIs, such as COVID-19, this review examined whether vitamin D supplementation can be supported as a nutritional strategy for reducing risk of infection, complications, and mortality from COVID-19 and found that the relationship between vitamin D and RTIs warrants further exploration.

Vitamin D supplementation in patients with atopic dermatitis, chronic urticaria and contact irritant and allergic dermatitis - possible improvement without risk

Abstract.

Prediction Model between Serum Vitamin D and Neurological Deficit in Cerebral Infarction Patients Based on Machine Learning

Objective

Vitamin D is associated with neurological deficits in patients with cerebral infarction. This study uses machine learning to evaluate the prediction model's efficacy of the correlation between vitamin D and neurological deficit in patients with cerebral infarction.

Methods

A total of 200 patients with cerebral infarction admitted to the Department of Neurology of our hospital from July 2018 to June 2019 were selected. The patients were randomly divided into a training set (n = 140) and a test set (n = 60) in a 7 : 3 ratio. The prediction model is constructed from the training set's data, and the model's prediction effect was evaluated by test set data. The area under the receiver operator characteristic curve was used to assess the prediction efficiency of models.

Results

In the training set, the area under the curve (AUC) of the logistic regression model and XGBoost algorithm model was 0.727 (95% CI: 0.601~0.854) and 0.818 (95% CI: 0.734~0.934), respectively. While in the test set, the AUC of the logistic regression model and XGBoost algorithm model was 0.761 (95% CI: 0.640~0.882) and 0.786 (95% CI: 0.670~0.902), respectively.

Conclusion

The prediction model of the correlation between vitamin D and neurological deficit in patients with cerebral infarction based on machine learning has a good prediction efficiency.

Analyzing the relationship between the vitamin D deficiency and COVID-19 mortality rate and modeling the time-delay interactions between body's immune healthy cells, infected cells, and virus particles with the effect of vitamin D levels

This paper presents some recent views on the aspects of vitamin D levels in relation to the COVID-19 infections and analyzes the relationship between the prevalence rates of vitamin D deficiency and COVID-19 death rates per million of various countries in Europe and Asia using the data from the PubMed database. The paper also discusses a new mathematical model of time-delay interactions between the body's immune healthy cells, infected cells, and virus particles with the effect of vitamin D levels. The model can be used to monitor the timely progression of healthy immune cells with the effects of the levels of vitamin D and probiotics supplement. It also can help to predict when the infected cells and virus particles free state can ever be reached as time progresses. The consideration of the time delay in the modeling due to effects of the infected cells or virus particles and the growth of healthy cells is also an important factor that can significantly change the outcomes of the body's immune cells as well as the infections.