Vitamin D supplementation for the treatment of COVID-19: A systematic review and meta-analysis of randomized controlled trials

Association of vitamin B12, folate, and homocysteine with COVID-19 severity and mortality: A systematic review and meta-analysis

Objective

We aimed to review the available evidence on the association between vitamin B12, folate, and homocysteine levels with worse outcomes among COVID-19 patients.

Methods

The search was carried out in ten databases simultaneously run on 10 May 2023, without language restrictions. We included cross-sectional, case-control, and cohort studies. The random-effects meta-analysis was performed using the Sidik-Jonkman method and corrected 95% confidence intervals using the truncated Knapp-Hartung standard errors. Standardized mean difference and 95% CI was used as the measure effect size.

Results

Thirteen articles were included in this review (n = 2134). Patients with COVID-19 who did not survive had the highest serum vitamin B12 values (SMD: 1.05; 95% CI: 0.31-1.78; p = 0.01, I2 = 91.22%). In contrast, low serum folate values were associated with patients with severe COVID-19 (SMD: -0.77; 95% CI: -1.35 to -0.19; p = 0.02, I2 = 59.09%). The remaining tested differences did not yield significant results.

Conclusion

Elevated serum levels of vitamin B12 were associated with higher mortality in patients with COVID-19. Severe cases of COVID-19 were associated with low serum folate levels. Future studies should incorporate a larger sample size.

Effect of Vitamin D3 Supplementation on Severe COVID-19: A Meta-Analysis of Randomized Clinical Trials

Since the beginning of the COVID-19 pandemic, vitamin D has attracted interest due to its immunomodulatory properties. Numerous studies show a correlation between vitamin D levels and COVID-19 cases and mortality. Therefore, we conducted a meta-analysis in order to assess the relationship between vitamin D3 supplementation and COVID-19 severity. We included 13 randomized clinical trials that contained the analyzed endpoints: length of COVID-19 hospitalization, number of intensive care unit (ICU) admissions, length of stay in the ICU, number of cases requiring any supplemental oxygenation, duration of any supplemental oxygenation, number of overall mortality and number of deaths associated with COVID-19. The relative risk with 95% confidence interval (CI) and the mean difference with 95% CI were calculated to compare the effect. A random effects model was used to calculate effect sizes. Our meta-analysis showed a positive effect of vitamin D3 supplementation on ICU admission (RR = 0.73; 95% CI [0.57; 0.95], p = 0.02, I2 = 19.6%) and mortality associated with COVID-19 among patients (RR = 0.56; 95% CI [0.34; 0.91]; p = 0.02; I2 = 0%). Vitamin D3 supplementation may potentially reduce the risk of ICU admission and death associated with COVID-19.

Label-Free Metal-Oxide Transistor Biosensors for Metabolite Detection in Human Saliva

Metabolites are essential molecules involved in various metabolic processes, and their deficiencies and excessive concentrations can trigger significant physiological consequences. The detection of multiple metabolites within a non-invasively collected biofluid could facilitate early prognosis and diagnosis of severe diseases. Here, a metal oxide heterojunction transistor (HJ-TFT) sensor is developed for the label-free, rapid detection of uric acid (UA) and 25(OH)Vitamin-D3 (Vit-D3) in human saliva. The HJ-TFTs utilize a solution-processed In2 O3 /ZnO channel functionalized with uricase enzyme and Vit-D3 antibody for the selective detection of UA and Vit-D3, respectively. The ultra-thin tri-channel architecture facilitates strong coupling between the electrons transported along the buried In2 O3 /ZnO heterointerface and the electrostatic perturbations caused by the interactions between the surface-immobilized bioreceptors and target analytes. The biosensors can detect a wide range of concentrations of UA (from 500 nm to 1000 µM) and Vit-D3 (from 100 pM to 120 nm) in human saliva within 60 s. Moreover, the biosensors exhibit good linearity with the physiological concentration of metabolites and limit of detections of ≈152 nm for UA and ≈7 pM for Vit-D3 in real saliva. The specificity is demonstrated against various interfering species, including other metabolites and proteins found in saliva, further showcasing its capabilities.

Association between Average Vitamin D Levels and COVID-19 Mortality in 19 European Countries-A Population-Based Study

Early epidemic reports have linked low average 25(OH) vitamin D levels with increased COVID-19 mortality. However, there has been limited updated research on 25(OH) vitamin D and its impact on COVID-19 mortality. This study aimed to update the initial report studying the link between vitamin D deficiency and COVID-19 mortality by using multi-country data in 19 European countries up to the middle of June 2023. COVID-19 data for 19 European countries included in this study were downloaded from Our World in Data from 1 March 2020, to 14 June 2023, and were included in the statistical analysis. The 25(OH) vitamin D average data were collected by conducting a literature review. A generalized estimation equation model was used to model the data. Compared to European countries with 25(OH) vitamin D levels of ≤50 nmol/L, European countries with 25(OH) vitamin D average levels greater than 50 nmol/L had lower COVID-19 mortality rates (RR = 0.794, 95% CI: 0.662-0.953). A statistically significant negative Spearman rank correlation was observed between 25(OH) vitamin D average levels and COVID-19 mortality. We also found significantly lower COVID-19 mortality rates in countries with high average 25(OH) vitamin D levels. Randomized trials on vitamin D supplementation are needed. In the meantime, the issue of vitamin D use should be debated in relation to the ongoing discussions of national post-COVID-19 resilience against future pandemics.

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.

Nutrition and immunity: lessons from coronavirus disease-2019

This review will provide an overview of the immune system and then describe the effects of frailty, obesity, specific micronutrients and the gut microbiota on immunity and susceptibility to infection including data from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic where relevant. A key role for the immune system is providing host defence against pathogens. Impaired immunity predisposes to infections and to more severe infections and weakens the response to vaccination. A range of nutrients, including many micronutrients, play important roles in supporting the immune system to function. The immune system can decline in later life and this is exaggerated by frailty. The immune system is also weakened with obesity, generalised undernutrition and micronutrient deficiencies, which all result in increased susceptibility to infection. Findings obtained during the SARS-CoV-2 pandemic support what was already known about the effects of ageing, frailty and obesity on immunity and susceptibility to infection. Observational studies conducted during the pandemic also support previous findings that multiple micronutrients including vitamins C, D and E, zinc and selenium and long-chain n-3 fatty acids are important for immune health, but whether these nutrients can be used to treat those already with coronavirus disease discovered in 2019 (COVID-19), particularly if already hospitalised, is uncertain from current inconsistent or scant evidence. There is gut dysbiosis in patients with COVID-19 and studies with probiotics report clinical improvements in such patients. There is an inverse association between adherence to a healthy diet and risk of SARS-CoV-2 infection and hospitalisation with COVID-19 which is consistent with the effects of individual nutrients and other dietary components. Addressing frailty, obesity and micronutrient insufficiency will be important to reduce the burden of future pandemics and nutritional considerations need to be a central part of the approach to preventing infections, optimising vaccine responses and promoting recovery from infection.

The Intersection Between COVID-19, Cardiovascular Disease, and Diet: a Review

PURPOSE OF REVIEW

Cardiovascular disease (CVD) is one of the top comorbidities associated with COVID-19-both pre- and post-infection. This review examines the relationships between COVID-19 infection and cardiovascular health, with a specific focus on diet as an important modifiable risk factor.

RECENT FINDINGS

Pandemic era studies of individuals battling and recovering from COVID-19 infection suggest a strong link between metabolic diseases, such as CVD, and SARS-CoV-2 infection susceptibility and severity. Other studies also demonstrate how COVID-19 lockdown policies and quarantine recommendations led to drastic lifestyle changes associated with increased CVD risk, such as reduced physical activity and lower diet quality. At the same time, new research is emerging that plant-based diets, which have previously been associated with lower CVD risk, may lower COVID-19 infection rates and severity of symptoms. Diet, COVID-19, and CVD intersect through complex biological mechanisms and related behavioral factors evidenced by clinical trials and epidemiological studies. Diet may be a critical tool for modifying risk of communicable and non-communicable conditions in the post-pandemic world.

Correlates of poor clinical outcomes related to COVID-19 among older people with psychiatric illness - a mixed methods study

OBJECTIVE

COVID-19 may lead to a range of clinical outcomes among older people with psychiatric and medical conditions. Evidence guiding management of future outbreaks among this vulnerable population in psychiatric hospital settings are sparse. In this study, we examined the correlates of poor clinical outcomes related to COVID-19 and explored the perspectives of COVID-19 survivors hospitalized in psychiatry settings.

METHOD

The correlates of poor clinical outcomes related to COVID-19 were examined using a retrospective chart review of 81 older people hospitalized in psychiatry settings. Correlates of clinical outcomes related to COVID-19 were assessed by multiple logistic regression models. In addition, the perspectives of 10 COVID-19 survivors were explored by qualitative interviews. The qualitative data was subject to thematic analysis.

RESULTS

Although 25.9% (n = 21) participants were asymptomatic, there was high COVID-19 related mortality (14.8%; n = 12). Vitamin-D deficiency, anticholinergic burden, and isolation policies within psychiatric wards were significantly (p < 0.05) related to COVID-19 related deaths. In qualitative interviews, participants emphasized the importance of strengthening local support networks and making vaccination centers more accessible.

CONCLUSIONS

Reducing anticholinergic prescriptions and improving isolation policies may help to mitigate poor clinical outcomes. Future research investigating the impact of vitamin-D supplementation on COVID-19 related outcomes is warranted.

The Role of Diet and Specific Nutrients during the COVID-19 Pandemic: What Have We Learned over the Last Three Years?

Nutrients and diets have an important impact on our immune system and infection risk and a huge number of papers have been published dealing with various aspects of nutrition in relation to SARS-CoV-2 infection risk or COVID-19 severity. This narrative review aims to give an update on this association and tries to summarize some of the most important findings after three years of pandemic. The analysis of major studies and systematic reviews leads to the conclusion that a healthy plant-based diet reduces the risks for SARS-CoV-2 infection and especially COVID-19 severity. Regarding micronutrients, vitamin D is to the fore, but also zinc, vitamin C and, to some extent, selenium may play a role in COVID-19. Furthermore, omega-3-fatty acids with their anti-inflammatory effects also deserve attention. Therefore, a major aim of societal nutritional efforts in future should be to foster a high quality plant-based diet, which not only exerts beneficial effects on the immune system but also reduces the risk for non-communicable diseases such as type 2 diabetes or obesity which are also primary risk factors for worse COVID-19 outcomes. Another aim should be to focus on a good supply of critical immune-effective nutrients, such as vitamin D and zinc.

Vitamin D Deficiency Prevalence in Hospitalized Patients with COVID-19 Significantly Decreased during the Pandemic in Slovakia from 2020 to 2022 Which Was Associated with Decreasing Mortality

The coronavirus disease 2019 (COVID-19) pandemic has led to changes in lifestyle, which could influence vitamin D status on a population level. The purpose of our study was to compare 25-hydroxyvitamin D (25[OH]D) levels in patients hospitalized because of severe COVID-19 during two waves of the pandemic (2020/21 vs. 2021/22). A total of 101 patients from the 2021/22 wave were compared with 101 sex- and age-matched subjects from the 2020/21 wave. Patients from both groups were hospitalized during the winter season from 1 December to 28 February. Men and women were analyzed together and separately. The mean 25(OH)D concentration increased from 17.8 ± 9.7 ng/mL to 25.2 ± 12.6 ng/mL between waves. The prevalence of vitamin D deficiency (<20 ng/mL) decreased from 82% to 54%. The prevalence of adequate serum 25(OH)D concentration (>30 ng/mL) increased from 10% to 34% (p < 0.0001). The proportion of patients with a history of vitamin D supplementation increased from 18% to 44% (p < 0.0001). Low serum 25(OH)D concentration was independently associated with mortality after adjusting for age and sex for the whole cohort of patients (p < 0.0001). The prevalence of inadequate vitamin D status in hospitalized patients with COVID-19 in Slovakia decreased significantly, probably due to a higher rate of vitamin D supplementation during the COVID-19 pandemic.

Vitamin D, Menopausal Health and COVID-19: Critical Appraisal of Current Data

Inconsistency exists across studies conducted in postmenopausal women regarding the effect of vitamin D deficiency (VDD) and supplementation on several aspects of menopausal health, such as fractures, vasomotor symptomatology, cardiovascular disease (CVD), cancer and infections, including coronavirus disease 2019 (COVID-19). The aim of this review is to critically summarize the evidence provided by observational studies and randomized controlled trials (RCTs) of vitamin D supplementation in postmenopausal women with VDD. Observational studies have found that VDD is associated with an increased risk of falls and fractures after the menopause. VDD also has a negative effect on menopausal symptomatology. VDD, especially its severe form, is associated with an increased risk of CVD risk factors and CVD events. VDD is associated with increased risk and mortality from several cancer types and risk of infections. The evidence from RCTs regarding the effect of vitamin D supplementation on falls, fractures, menopausal symptoms, cardiovascular disease, cancer and infections is not robust. Thus, skeletal health may benefit only when vitamin D is co-administered with calcium, especially in those ≥70 years old and with severe VDD. There is no evidence of a favorable effect on menopausal symptoms or risk of CVD or cancer, except for a modest reduction in cancer-related mortality. Inconsistency still exists regarding its effect on infection risk, disease severity and mortality due to COVID-19.