Vitamin D Deficiency and Low Serum Calcium as Predictors of Poor Prognosis in Patients with Severe COVID-19

Dietary mineral intakes predict Coronavirus-disease 2019 (COVID-19) incidence and hospitalization in older adults

BACKGROUND

The aim of this study was to determine the association between dietary mineral intake and Coronavirus-disease 2019 (COVID-19) infection and its associated hospitalization.

METHODS

This cohort study utilized the MASHAD study population, which comprised individuals aged 35-65. Upon recruitment in 2007, dietary intake was documented using a validated 65-item food frequency questionnaire (FFQ). Data on COVID-19 PCR test results was collected from all relevant medical centers in Mashhad between February 2020 and June 2022. The regression model included dietary minerals and employed the backward variable selection method, along with advanced data analysis techniques.

RESULTS

The final analysis involved 1957 participants, including 193 COVID-19-positive patients. The mean age was 49.71 and 50.28 years in the COVID-19-positive and negative groups, respectively (p = 0.12). Dietary intakes of magnesium, iron, and potassium were notably lower in COVID-19-positive patients (P < 0.05). Following adjustments for age and sex, dietary iron remained significantly associated with COVID-19 incidence (OR = 0.94, 95% CI: 0.90-0.98). Furthermore, a statistically significant relationship was observed between dietary zinc and hospitalization due to COVID-19 (OR = 0.69, 95% CI: 0.51-0.93). In dynamical system models, intakes of calcium, zinc, and iron below the cut-offs of 1138, 9.7, and 8.17 mg/day, respectively, were linked to an increased risk of COVID-19 incidence.

CONCLUSION

Higher dietary iron and zinc intake are associated with decreased risk of COVID-19 infection and hospitalization, respectively.

U-SHAPED ASSOCIATION BETWEEN SERUM CALCIUM LEVELS AND 28-DAY MORTALITY IN PATIENTS WITH SEPSIS: A RETROSPECTIVE ANALYSIS OF THE MIMIC-III DATABASE

ABSTRACT

Background: Serum calcium levels disorder have been reported to be associated with poor prognosis in different diseases. Studies on the association between serum calcium and outcomes of septic patients remained limited. The aim of this study is to investigate the association between serum calcium and 28-day mortality in septic patients. Method: Patients diagnosed with sepsis in the Medical Information Mart for Intensive Care III database were included. Patients were divided into five groups according to the quintiles of serum calcium levels, and their baseline characteristics were compared. Multivariate Cox regression models were used to assess the association between serum calcium and 28-day mortality. Smooth curve fitting and segmented regression models were used to visualize the association between serum calcium levels and 28-day mortality risk. The 28-day survival probability between five groups was analyzed using Kaplan-Meier curves. Results: A total of 3,016 patients with sepsis were enrolled, and the 28-day mortality rate was 35.64%. After adjusting for confounders, compared with the reference quintile (Q4: 9.00-9.50), the lowest serum calcium level quintile (Q1: 5.70-8.20) was independently associated with an increased risk of 28-day mortality (hazard ratio [HR], 2.12; 95% CI, 1.76-2.56). Smooth spline fitting revealed a U-shaped association between serum calcium and 28-day mortality. When serum calcium was <9.0 mg/dL, 28-day mortality risk increased by 58% per unit decrease in serum calcium (HR, 0.42; 95% CI, 0.37-0.48). When serum calcium was >9.0 mg/dL, the 28-day mortality risk increased by 12% per unit increase in serum calcium (HR, 1.12; 95% CI, 1.04-1.20). Conclusion: A U-shaped association was observed between serum calcium levels and 28-day mortality in septic patients. Lower or higher serum calcium levels were associated with increased risk of 28-day mortality in septic patients.

Potential impacts of SARS-CoV-2 on parathyroid: current advances and trends

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection affects several important organs including endocrine glands. Experimental studies demonstrated that the virus exploits the ACE2, a transmembrane glycoprotein on the cell surface as a receptor for cellular entry. This entry process is exclusively facilitated by other intracellular protein molecules such as TMPRSS2, furin, NRP1, and NRP2. Recent findings documented the involvement of the SARS-CoV-2 in inducing various parathyroid disorders including hypoparathyroidism and hypocalcemia, which received significant attention. This review extensively describes rapidly evolving knowledge on the potential part of SARS-CoV-2 in emerging various parathyroid disorders due to SARS-CoV-2 infection particularly parathyroid malfunction in COVID-19 cases, and post-COVID-19 conditions. Further, it presents the expression level of various molecules such as ACE2, TMPRSS2, furin, NRP1, and NRP2 in the parathyroid cells that facilitate the SARS-CoV-2 entry into the cell, and discusses the possible mechanism of parathyroid gland infection. Besides, it explores parathyroid malfunction in COVID-19 vaccine-administered cases. It also explains the possible long-COVID-19 effect on parathyroid and post-COVID-19 management of parathyroid. A complete understanding of the mechanisms of SARS-CoV-2-triggered pathogenesis in parathyroid dysfunctions may curtail treatment options and aid in the management of SARS-CoV-2-infected cases.

Calcium, Phosphorus and Magnesium Abnormalities Associated with COVID-19 Infection, and Beyond

The coronavirus disease (COVID-19) pandemic caused by the novel coronavirus SARS-CoV-2 has had a profound impact on global health, leading to a surge in research to better understand the pathophysiology of the disease. Among the various aspects under investigation, disruptions in mineral homeostasis have emerged as a critical area of interest. This review aims to provide an overview of the current evidence linking calcium, phosphorus and magnesium abnormalities with COVID-19 infection and explores the potential implications beyond the acute phase of the disease. Beyond the acute phase of COVID-19, evidence suggests a potential impact of these mineral abnormalities on long-term health outcomes. Persistent alterations in calcium, phosphorus and magnesium levels have been linked to increased cardiovascular risk, skeletal complications and metabolic disorders, warranting continuous monitoring and management in post-COVID-19 patients.

Vitamin D as a prognostic biomarker in COVID-19: single-center study and meta-analyses

Vitamin D was investigated as a prognostic biomarker in COVID-19, in relation to both disease susceptibility and outcomes in infected individuals. Patients admitted to the hospital with a confirmed COVID-19 diagnosis were included if they had a vitamin D measurement prior to hospitalization. Using age- and sex-matched controls, vitamin D levels were investigated for an association with COVID-19 related hospitalizations. Further, vitamin D levels were investigated for an association with 30-day mortality in hospitalized COVID-19 patients. Additionally, three meta-analyses were conducted, investigating the association of vitamin D with the following outcomes: Having a positive SARS-CoV-2 test, hospitalization with COVID-19, and mortality in COVID-19 patients. A total of 685 hospitalized COVID-19 patients were included in the single-center study. Compared to controls, they had higher vitamin D levels. Unadjusted analysis of these 685 cases found higher vitamin D levels associated with increased 30-day mortality. This association disappeared after adjusting for age. In the fully adjusted model, no association between vitamin D and 30-day mortality was found. The meta-analyses found significant associations between lower vitamin D and having a positive SARS-CoV-2 test, and mortality among hospital-admitted COVID-19 patients. The relationship between lower vitamin D and COVID-19 related hospital admissions trended towards being positive but was not statistically significant. Many factors seem to influence the associations between vitamin D and COVID-19 related outcomes. Consequently, we do not believe that vitamin D in and of itself is likely to be a clinically useful and widely applicable predictor for the susceptibility and severity of COVID-19 infections.

The interplay between hypovitaminosis D and the immune dysfunction in the arteriovenous thrombotic complications of the sever coronavirus disease 2019 (COVID-19) infection

Thromboembolic complications including cerebrovascular accidents, pulmonary embolism, myocardial infarction, deep vein thrombosis and disseminating intravascular coagulopathy are serious encounters in sever coronavirus disease 2019 (COVID-19) infected patients. This worsens the prognosis and may lead to death or life long morbidities. The laboratory finding of the disturbed haemostasias and the hyperinflammatory response are almost invariably present in COVID-19 patients. Multiple treatment modalities are utilized by the healthcare professionals to overcome the cytokine storm, oxidative stress, endothelial dysfunction, and coagulopathy in these patients. The combined actions of vitamin D (VitD) as a steroid hormone with anti-inflammatory, immunomodulatory, and antithrombotic properties increase the potential of the possible involvement of hypovitaminosis D in the thromboembolic complications of COVID-19 infection, and stimulated researchers and physicians to administer VitD therapy to prevent the infection and/or overcome the disease complications. The current review highlighted the immunomodulatory, anti-inflammatory, antioxidative and hemostatic functions of VitD and its interrelation with the renin-angiotensin-aldosterone system (RAAS) pathway and the complement system. Additionally, the association of VitD deficiency with the incidence and progression of COVID-19 infection and the associated cytokine storm, oxidative stress, hypercoagulability, and endothelial dysfunction were emphasized. Normalizing VitD levels by daily low dose therapy in patients with hypovitaminosis D below (25 nmol/l) is essential for a balanced immune response and maintaining the health of the pulmonary epithelium. It protects against upper respiratory tract infections and decreases the complications of COVID-19 infections. Understanding the role of VitD and its associated molecules in the protection against the coagulopathy, vasculopathy, inflammation, oxidative stress and endothelial dysfunction in COVID-19 infection could lead to new therapeutic strategies to prevent, treat, and limit the complications of this deadly virus infection.

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.

Guild-Level Microbiome Signature Associated with COVID-19 Severity and Prognosis

Coronavirus disease 2019 (COVID-19) severity has been associated with alterations of the gut microbiota. However, the relationship between gut microbiome alterations and COVID-19 prognosis remains elusive. Here, we performed a genome-resolved metagenomic analysis on fecal samples from 300 in-hospital COVID-19 patients, collected at the time of admission. Among the 2,568 high quality metagenome-assembled genomes (HQMAGs), redundancy analysis identified 33 HQMAGs which showed differential distribution among mild, moderate, and severe/critical severity groups. Co-abundance network analysis determined that the 33 HQMAGs were organized as two competing guilds. Guild 1 harbored more genes for short-chain fatty acid biosynthesis, and fewer genes for virulence and antibiotic resistance, compared with Guild 2. Based on average abundance difference between the two guilds, the guild-level microbiome index (GMI) classified patients from different severity groups (average AUROC [area under the receiver operating curve] = 0.83). Moreover, age-adjusted partial Spearman's correlation showed that GMIs at admission were correlated with 8 clinical parameters, which are predictors for COVID-19 prognosis, on day 7 in hospital. In addition, GMI at admission was associated with death/discharge outcome of the critical patients. We further validated that GMI was able to consistently classify patients with different COVID-19 symptom severities in different countries and differentiated COVID-19 patients from healthy subjects and pneumonia controls in four independent data sets. Thus, this genome-based guild-level signature may facilitate early identification of hospitalized COVID-19 patients with high risk of more severe outcomes at time of admission. IMPORTANCE Previous reports on the associations between COVID-19 and gut microbiome have been constrained by taxonomic-level analysis and overlook the interaction between microbes. By applying a genome-resolved, reference-free, guild-based metagenomic analysis, we demonstrated that the relationship between gut microbiota and COVID-19 is genome-specific instead of taxon-specific or even species-specific. Moreover, the COVID-19-associated genomes were not independent but formed two competing guilds, with Guild 1 potentially beneficial and Guild 2 potentially more detrimental to the host based on comparative genomic analysis. The dominance of Guild 2 over Guild 1 at time of admission was associated with hospitalized COVID-19 patients at high risk for more severe outcomes. Moreover, the guild-level microbiome signature is not only correlated with the symptom severity of COVID-19 patients, but also differentiates COVID-19 patients from pneumonia controls and healthy subjects across different studies. Here, we showed the possibility of using genome-resolved and guild-level microbiome signatures to identify hospitalized COVID-19 patients with a high risk of more severe outcomes at the time of admission.

25 Hydroxyvitamin D Serum Concentration and COVID-19 Severity and Outcome-A Retrospective Survey in a Romanian Hospital

Interest in the immunomodulatory function of vitamin D has grown since the COVID-19 pandemic started. Our study investigated the possible association between vitamin D deficiency and COVID-19 severity, intensive care needs, and mortality in patients hospitalized with COVID-19. A prospective cohort study was performed on 2342 COVID-19 hospitalized patients between April 2020 and May 2022 in a Romanian tertiary hospital for infectious diseases. A multivariate generalized linear model for binary data was fit with dependent variables: severe/critical form of COVID-19, intensive care need, and fatal outcome as a function of vitamin D deficiency, controlling for age, comorbidities, and vaccination status. More than half of the patients (50.9%) were classified with vitamin D deficiency based on a serum concentration of less than 20 ng/mL. There was a negative association between vitamin D and age. Vitamin D-deficient patients presented with more cardiovascular, neurological, and pulmonary diseases, as well as diabetes, and cancer. In multivariate logistic regression models, vitamin D-deficient patients had higher odds of severe/critical forms of COVID-19 [OR = 1.23 (95% CI 1.03-1.47), p = 0.023] and higher odds of death [OR = 1.49 (95% CI 1.06-2.08), p = 0.02]. Vitamin D deficiency was associated with disease severity and death outcome in hospitalized COVID-19 patients.

Admission eGFR predicts in-hospital mortality independently of admission glycemia and C-peptide in patients with type 2 diabetes mellitus and COVID-19

OBJECTIVE

Type 2 diabetes mellitus (T2DM) and impaired kidney function are associated with a higher risk of poor outcomes of COVID-19. We conducted a retrospective study in hospitalized T2DM patients with COVID-19 to assess the association between in-hospital mortality and admission values of different hematological/biochemical parameters, including estimated glomerular filtration rate (eGFR), plasma glucose and C-peptide (as a marker of beta-cell function).

METHODS

The study included T2DM patients with confirmed SARS-CoV-2 infection who were consecutively admitted to our Institution between October 1, 2020 and April 1, 2021.

RESULTS

Patients (n = 74) were categorized into survivors (n = 55) and non-survivors (n = 19). Non-survivors exhibited significantly higher median WBC count, D-dimer, neutrophil-to-lymphocyte ratio, hsCRP, and procalcitonin levels, as well as significantly lower median serum 25(OH)D levels compared to survivors. Non-survivors exhibited significantly higher median admission plasma glucose (APG) values compared to survivors (210 vs 166 mg/dL; p = 0.026). There was no statistically significant difference in median values of plasma C-peptide between non-survivors and survivors (3.55 vs 3.24 ng/mL; p = 0.906). A significantly higher percentage of patients with an eGFR < 60 mL/min/1.73 m² was observed in the non-survivor group as compared to the survivor group (57.9% vs 23.6%; p = 0.006). A multivariate analysis performed by a logistic regression model after adjusting for major confounders (age, sex, body mass index, major comorbidities) showed a significant inverse association between eGFR values and risk of in-hospital mortality (OR, 0.956; 95% CI, 0.931-0.983; p = 0.001). We also found a significant positive association between WBC count and risk of in-hospital mortality (OR, 1.210; 95% CI, 1.043-1.404; p = 0.011).

CONCLUSIONS

Admission eGFR and WBC count predict in-hospital COVID-19 mortality among T2DM patients, independently of traditional risk factors, APG and random plasma C-peptide. Hospitalized patients with COVID-19 and comorbid T2DM associated with impaired kidney function at admission should be considered at high risk for adverse outcomes and death.

Electrolyte imbalances as poor prognostic markers in COVID-19: a systemic review and meta-analysis

PURPOSE

Serum electrolyte imbalances are highly prevalent in COVID-19 patients. However, their associations with COVID-19 outcomes are inconsistent, and of unknown prognostic value. We aim to systematically clarify the associations and prognostic accuracy of electrolyte imbalances (sodium, calcium, potassium, magnesium, chloride and phosphate) in predicting poor COVID-19 clinical outcome.

METHODS

PubMed, Embase and Cochrane Library were searched. Odds of poor clinical outcome (a composite of mortality, intensive-care unit (ICU) admission, need for respiratory support and acute respiratory distress syndrome) were pooled using mixed-effects models. The associated prognostic sensitivity, positive and negative likelihood ratios (LR + , LR-) and predictive values (PPV, NPV; assuming 25% pre-test probability), and area under the curve (AUC) were computed.

RESULTS

We included 28 observational studies from 953 records with low to moderate risk-of-bias. Hyponatremia (OR = 2.08, 95% CI = 1.48-2.94, I² = 93%, N = 8), hypernatremia (OR = 4.32, 95% CI = 3.17-5.88, I² = 45%, N = 7) and hypocalcemia (OR = 3.31, 95% CI = 2.24-4.88, I² = 25%, N = 6) were associated with poor COVID-19 outcome. These associations remained significant on adjustment for covariates such as demographics and comorbidities. Hypernatremia was 97% specific in predicting poor outcome (LR + 4.0, PPV = 55%, AUC = 0.80) despite no differences in CRP and IL-6 levels between hypernatremic and normonatremic patients. Hypocalcemia was 76% sensitive in predicting poor outcome (LR- 0.44, NPV = 87%, AUC = 0.71). Overall quality of evidence ranged from very low to moderate.

CONCLUSION

Hyponatremia, hypernatremia and hypocalcemia are associated with poor COVID-19 clinical outcome. Hypernatremia is 97% specific for a poor outcome, and the association is independent of inflammatory marker levels. Further studies should evaluate if correcting these imbalances help improve clinical outcome.

Association of CYP24A1 Gene rs6127099 (A > T) Polymorphism with Lower Risk to COVID-19 Infection in Kazakhstan

In December 2019, SARS-CoV-2 was identified in Wuhan, China. Infection by SARS-CoV-2 causes coronavirus disease 2019 (COVID-19), which is characterized by fever, cough, dyspnea, anosmia, and myalgia in many cases. There are discussions about the association of vitamin D levels with COVID-19 severity. However, views are conflicting. The aim of the study was to examine associations of vitamin D metabolism pathway gene polymorphisms with symptomless COVID-19 susceptibility in Kazakhstan. The case-control study examined the association between asymptomatic COVID-19 and vitamin D metabolism pathway gene polymorphisms in 185 participants, who previously reported not having COVID-19, were PCR negative at the moment of data collection, and were not vaccinated. A dominant mutation in rs6127099 (CYP24A1) was found to be protective of asymptomatic COVID-19. Additionally, the G allele of rs731236 TaqI (VDR), dominant mutation in rs10877012 (CYP27B1), recessive rs1544410 BsmI (VDR), and rs7041 (GC) are worth consideration since they were statistically significant in bivariate analysis, although their independent effect was not found in the adjusted multivariate logistic regression model.

Serum Calcium, Magnesium, and Phosphorus Levels in Patients with COVID-19: Relationships with Poor Outcome and Mortality

In this retrospective study to assess the impact of serum corrected calcium (CorrCa), magnesium (Mg) and phosphorus (P) levels, all adult patients with laboratory-confirmed COVID-19 hospitalized during 2020 were included. Poor outcome was considered in patients who presented need for mechanical ventilation, intensive care unit (ICU) admission, or in-hospital mortality. We analyzed 2473 patients (956 females) aged (mean±SD) 63.4±15.9 years. During admission, 169 patients (6.8%) required mechanical ventilation, 205 (8.3%) were admitted to the ICU, and 270 (10.9%) died. Composite variable of poor outcome, defined as need for mechanical ventilation, ICU admission or death, was present in 434 (17.5%) patients. In univariate analysis, the need for mechanical ventilation was positively related to Mg levels (OR 8.37, 95% CI 3.62-19.33; p<0.001); ICU admission was related to CorrCa (OR 0.49, 95% CI 0.25-0.99; p=0.049) and Mg levels (OR 5.81, 95% CI 2.74-12.35; p<0.001); and in-hospital mortality was related to CorrCa (OR 1.73, 95% CI 1.14-2.64; p=0.011). The composite variable of poor outcome was only related to Mg (OR 2.68, 95% CI 1.54-4.68; p=0.001). However, in multivariate analysis only CorrCa was significantly related to the need for mechanical ventilation (OR 0.19, 95% CI 0.05-0.72; p=0.014) and ICU admission (OR 0.25; 95% CI 0.09-0.66; p=0.005), but not with in-hospital mortality or the composite variable. In conclusion, CorrCa can be used as a simple and reliable marker of poor outcome in patients with COVID-19, although not to predict the risk of in-hospital mortality.

The calcium-sensing receptor in inflammation: Recent updates

The Calcium-Sensing Receptor (CaSR) is a member of the class C of G-proteins coupled receptors (GPCRs), it plays a pivotal role in calcium homeostasis by directly controlling calcium excretion in the kidneys and indirectly by regulating parathyroid hormone (PTH) release from the parathyroid glands. The CaSR is found to be ubiquitously expressed in the body, playing a plethora of additional functions spanning from fluid secretion, insulin release, neuronal development, vessel tone to cell proliferation and apoptosis, to name but a few. The present review aims to elucidate and clarify the emerging regulatory effects that the CaSR plays in inflammation in several tissues, where it mostly promotes pro-inflammatory responses, with the exception of the large intestine, where contradictory roles have been recently reported. The CaSR has been found to be expressed even in immune cells, where it stimulates immune response and chemokinesis. On the other hand, CaSR expression seems to be boosted under inflammatory stimulus, in particular, by pro-inflammatory cytokines. Because of this, the CaSR has been addressed as a key factor responsible for hypocalcemia and low levels of PTH that are commonly found in critically ill patients under sepsis or after burn injury. Moreover, the CaSR has been found to be implicated in autoimmune-hypoparathyroidism, recently found also in patients treated with immune-checkpoint inhibitors. Given the tight bound between the CaSR, calcium and vitamin D metabolism, we also speculate about their roles in the pathogenesis of severe acute respiratory syndrome coronavirus-19 (SARS-COVID-19) infection and their impact on patients' prognosis. We will further explore the therapeutic potential of pharmacological targeting of the CaSR for the treatment and management of aberrant inflammatory responses.

Hypermagnesemia and hyperphosphatemia are highly prevalent in patients with COVID-19 and increase the risk of death

OBJECTIVES

Nonrespiratory manifestations of COVID-19 include endocrine disorders, among which are calcium-magnesium-phosphate homeostasis abnormalities, which seem to influence the disease severity and patient outcome. The aim of this study was to evaluate the prevalence and impact of calcium-magnesium-phosphate and vitamin D3 disorders on survival in patients hospitalized for COVID-19 depending on the severity of the disease and kidney function.

DESIGN OR METHODS

The study was conducted between April 2020 and May 2021 at Central Clinical Hospital in Warsaw, Poland. A total of 146 patients who had tested concentration of at least one of the studied elements, estimated glomerular filtration ratio, creatinine levels, and blood saturation, and were diagnosed with COVID-19 disease were included in the analysis.

RESULTS

We found that hypermagnesemia was common and associated with a 1.5-fold increased risk of death in the whole cohort. Hyperphosphatemia also increased the risk of death, exactly 2.4-fold. Furthermore, we found a statistically significant association between increased mortality in the whole cohort and hypovitaminosis D3 (P <0.05). Serum creatinine concentration and estimated glomerular filtration ratio significantly correlated with serum magnesium and phosphate levels.

CONCLUSION

Hypermagnesemia, hyperphosphatemia, and hypovitaminosis D but not hypocalcemia influence the mortality of patients with COVID-19. These parameters should be monitored routinely in this group of patients, especially in those with decreased kidney function.

The Mutual Relationship among Cardiovascular Diseases and COVID-19: Focus on Micronutrients Imbalance

Micronutrients are ions and vitamins humbly required by the human body. They play a main role in several physiological mechanisms and their imbalance is strongly associated with potentially-fatal complications. Micronutrient imbalance is associated with many cardiovascular diseases, such as arrythmias, heart failure, and ischemic heart disease. It has been also observed in coronavirus disease 2019 (COVID-19), particularly in most severe patients. The relationship between cardiovascular diseases and COVID-19 is mutual: the latter triggers cardiovascular disease onset and worsening while patients with previous cardiovascular disease may develop a more severe form of COVID-19. In addition to the well-known pathophysiological mechanisms binding COVID-19 and cardiovascular diseases together, increasing importance is being given to the impact of micronutrient alterations, often present during COVID-19 and able to affect the balance responsible for a good functioning of the cardiovascular system. In particular, hypokalemia, hypomagnesemia, hyponatremia, and hypocalcemia are strongly associated with worse outcome, while vitamin A and D deficiency are associated with thromboembolic events in COVID-19. Thus, considering how frequent the cardiovascular involvement is in patients with COVID-19, and how it majorly affects their prognosis, this manuscript provides a comprehensive review on the role of micronutrient imbalance in the interconnection between COVID-19 and cardiovascular diseases.

Effects of nutrients on immunomodulation in patients with severe COVID-19: Current knowledge

Recent research has demonstrated that critically ill patients with coronavirus disease 2019 (COVID-19) show significant immune system dysregulation. Due to that, some nutrients that influence immunomodulation have been suggested as a form of treatment against the infection. This review collected the information on the impact of vitamins on the prognosis of COVID-19, with the intention of facilitating treatment and prevention of the disease risk status in patients. The collected information was obtained using the PubMed electronic database by searching for articles that relate COVID-19 and the mechanisms/effects of the nutrients: Proteins, glucose, lipids, vitamin B12, vitamin D, calcium, iron, copper, zinc, and magnesium, including prospective, retrospective, and support articles. The findings reveal an optimal response related mainly to omega-3, eicosapentaenoic acid, docosahexaenoic acid, calcium, and iron that might represent benefits in the treatment of critically ill patients. However, nutrient supplementation should be done with caution due to the limited availability of randomized controlled studies.

Vitamin D and SARS-CoV2 infection, severity and mortality: A systematic review and meta-analysis

To assess the evidence on SARS-CoV2 infection and Covid-19 in relation to deficiency and supplementation of vitamin D, we conducted a systematic review up to April 2021. We summarised data from 38 eligible studies, which presented risk estimates for at least one endpoint, including two RCT and 27 cohort-studies: 205565 patients with information on 25OHD status and 2022 taking vitamin D supplementation with a total of 1197 admitted to the ICU or who needed invasive mechanical ventilation or intubation and hospital stay, and more than 910 Covid-19 deaths. Primary outcomes were severity and mortality and the main aim was to evaluate the association with vitamin D supplementation. Random effects models showed that supplementation was associated with a significant lower risk of both Covid-19 severe disease (SRR 0.38, 95% CI 0.20-0.72, 6 studies) and mortality (SRR 0.35, 95% CI 0.17-0.70, 8 studies). There were no statistically significant dose differences between studies: summary estimates with regular doses remain statistically significant, suggesting that higher doses are not necessary. For patients on vitamin D supplementation, a greater reduction in mortality risk emerged in older individuals and at higher latitudes. Regarding the quality of studies, assessed using the New Castle-Ottawa quality scale, the analysis revealed in most cases no statistically significant differences between low, medium or high quality studies. We found significant associations of vitamin D supplementation with Covid-19, encompassing risks of disease worsening and mortality, especially in seasons characterized by 25OHD deficiency and with not severe patients. Dedicated randomized clinical studies are encouraged to confirm these results.

Hypocalcemia in hospitalized patients with COVID-19: roles of hypovitaminosis D and functional hypoparathyroidism

INTRODUCTION

Despite the high prevalence of hypocalcemia in patients with COVID-19, very limited studies have been designed to evaluate etiologies of this disorder. This study was designed to evaluate the status of serum parameters involved in calcium metabolism in patients with COVID-19 and hypocalcemia.

MATERIALS AND METHODS

This cross-sectional study was conducted on 123 hospitalized patients with COVID-19. Serum concentrations of PTH, 25 (OH) D, magnesium, phosphate, and albumin were assessed and compared across three groups of moderate/severe hypocalcemia (serum total calcium < 8 mg/dl), mild hypocalcemia (8 mg/dl ≤ serum total calcium < 8.5 mg/dl) and normocalcemia (serum total calcium ≥ 8.5 mg/dl). Multivariate analyses were performed to evaluate the independent roles of serum parameters in hypocalcemia.

RESULTS

In total, 65.9% of the patients had hypocalcemia. Vitamin D deficiency was found in 44.4% and 37.7% of moderate/severe and mild hypocalcemia cases, respectively, compared to 7.1% in the normal serum total calcium group (P = 0.003). In multivariate analysis, vitamin D deficiency was independently associated with 6.2 times higher risk of hypocalcemia (P = 0.001). Only a minority of patients with hypocalcemia had appropriately high PTH (15.1% and 14.3% in mild and moderate/severe hypocalcemia, respectively). Serum PTH was low/low-normal in 40.0% of patients with moderate/severe low-corrected calcium group. Magnesium deficiency was not associated with hypocalcemia in univariate and multivariate analysis.

CONCLUSION

Vitamin D deficiency plays a major role in hypocalcemia among hospitalized patients with COVID-19. Inappropriately low/low-normal serum PTH may be a contributing factor in this disorder.

Genetically Predicted Circulating Concentrations of Micronutrients and COVID-19 Susceptibility and Severity: A Mendelian Randomization Study

Background

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which since 2019 has caused over 5 million deaths to date. The pathogenicity of the virus is highly variable ranging from asymptomatic to fatal. Evidence from experimental and observational studies suggests that circulating micronutrients may affect COVID-19 outcomes.

Objectives

To complement and inform observational studies, we investigated the associations of genetically predicted concentrations of 12 micronutrients (β-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B-6, vitamin B-12, vitamin D, and zinc) with SARS-CoV-2 infection risk and COVID-19 severity using Mendelian randomization (MR).

Methods

Two-sample MR was conducted using 87,870 individuals of European descent with a COVID-19 diagnosis and 2,210,804 controls from the COVID-19 host genetics initiative. Inverse variance-weighted MR analyses were performed with sensitivity analyses to assess the impact of potential violations of MR assumptions.

Results

Compared to the general population, nominally significant associations were noted for higher genetically predicted vitamin B-6 (Odds ratio per standard deviation [OR_SD]: 1.06; 95% confidence interval [CI]: 1.00, 1.13; p-value = 0.036) and lower magnesium concentrations (OR_SD: 0.33; 95%CI: 0.11, 0.96; P = 0.042) with COVID-19 infection risk. However, the association for magnesium was not consistent in some sensitivity analyses, and sensitivity analyses could not be performed for vitamin B-6 as only two genetic instruments were available. Genetically predicted levels of calcium, folate, β-carotene, copper, iron, vitamin B-12, vitamin D, selenium, phosphorus, or zinc were not associated with the outcomes from COVID-19 disease.

Conclusion

These results, though based only on genetically predicated circulating micronutrient concentrations, provide scant evidence for possible associations of micronutrients with COVID-19 outcomes.

Modifiable Host Factors for the Prevention and Treatment of COVID-19: Diet and Lifestyle/Diet and Lifestyle Factors in the Prevention of COVID-19

Many studies have shown that the immune system requires adequate nutrition to work at an optimal level. Not only do optimized nutritional strategies support the immune system, but they also reduce chronic inflammation. Nutritional supplements that are recommended for patients with critical illnesses are thought to also be effective for the coronavirus disease 2019 (COVID-19) patients in the intensive care unit. Some studies have recommended fresh fruits and vegetables, soy, nuts, and antioxidants, such as omega-3 fatty acids, to improve immune system activity. Although nutritional status is considered to be an important prognostic factor for patients with COVID-19, there is to date no sufficient evidence that optimal nutritional therapies can be beneficial for these patients. Some have argued that the COVID-19 pandemic is a good opportunity to test the effectiveness of nutritional intervention for infectious diseases. Many researchers have suggested that testing the proposed nutritional approaches for infectious diseases in the context of a pandemic would be highly informative. The authors of other review papers concluded that it is important to have a diet based on fresh foods, such as fruits, vegetables, whole grains, low-fat dairy products, and healthy fats (i.e., olive oil and fish oil), and to limit the intake of sugary drinks as well as high-calorie and high-salt foods. In this review, we discuss the clinical significance of functional food ingredients as complementary therapies potentially beneficial for the prevention or treatment of COVID-19. We believe that our review will be helpful to plan and deploy future studies to conclude these potentials against COVID-19, but also to new infectious diseases that may arise in the future.

Vitamin D status and COVID-19 severity

Background

Age, body mass index (BMI) and pre-existing comorbidities are known risk factors of severe coronavirus disease 2019 (COVID-19). In this study we explore the relationship between vitamin D status and COVID-19 severity.

Methods

We conducted a prospective, cross-sectional descriptive study. We enrolled 100 COVID-19 positive patients admitted to a tertiary level hospital in Johannesburg, South Africa. Fifty had symptomatic disease (COVID-19 pneumonia) and 50 who were asymptomatic (incidental diagnosis). Following written informed consent, patients were interviewed regarding age, gender and sunlight exposure during the past week, disease severity, BMI, calcium, albumin, magnesium and alkaline phosphatase levels. Finally, blood was collected for vitamin D measurement.

Results

We found an 82% prevalence rate of vitamin D deficiency or insufficiency among COVID-19 patients. Vitamin D levels were lower in the symptomatic group (18.1 ng/mL ± 8.1 ng/mL) than the asymptomatic group (25.9 ng/mL ± 7.1 ng/mL) with a p-value of 0.000. The relative risk of symptomatic COVID-19 was 2.5-fold higher among vitamin D deficient patients than vitamin D non-deficient patients (confidence interval [CI]: 1.14–3.26). Additional predictors of symptomatic disease were older age, hypocalcaemia and hypoalbuminaemia. Using multiple regression, the only independent predictors of COVID-19 severity were age and vitamin D levels. The patients exposed to less sunlight had a 2.39-fold increased risk for symptomatic disease compared to those with more sunlight exposure (CI: 1.32–4.33).

Conclusion

We found a high prevalence of vitamin D deficiency and insufficiency among patients admitted to hospital with COVID-19 and an increased risk for symptomatic disease in vitamin D deficient patients.

Prognostic and Therapeutic Role of Vitamin D in COVID-19: Systematic Review and Meta-analysis

PURPOSE

Vitamin D deficiency/insufficiency may increase the susceptibility to coronavirus disease 2019 (COVID-19). We aimed to determine the association between vitamin D deficiency/insufficiency and susceptibility to COVID-19, its severity, mortality, and role of vitamin D in its treatment.

METHODS

We searched CINAHL, Cochrane library, EMBASE, PubMED, Scopus, and Web of Science up to May 30, 2021, for observational studies on association between vitamin D deficiency/insufficiency and susceptibility to COVID-19, severe disease, and death among adults, and, randomized controlled trials (RCTs) comparing vitamin D treatment against standard care or placebo, in improving severity or mortality among adults with COVID-19. Risk of bias was assessed using Newcastle-Ottawa scale for observational studies and AUB-KQ1 Cochrane tool for RCTs. Study-level data were analyzed using RevMan 5.3 and R (v4.1.0). Heterogeneity was determined by I2 and sources were explored through prespecified sensitivity analyses, subgroup analyses, and meta-regressions.

RESULTS

Of 1877 search results, 76 studies satisfying eligibility criteria were included. Seventy-two observational studies were included in the meta-analysis (n = 1 976 099). Vitamin D deficiency/insufficiency increased the odds of developing COVID-19 (odds ratio [OR] 1.46; 95% CI, 1.28-1.65; P < 0.0001; I2 = 92%), severe disease (OR 1.90; 95% CI, 1.52-2.38; P < 0.0001; I2 = 81%), and death (OR 2.07; 95% CI, 1.28-3.35; P = 0.003; I2 = 73%). The 25-hydroxy vitamin D concentrations were lower in individuals with COVID-19 compared with controls (mean difference [MD] -3.85 ng/mL; 95% CI, -5.44 to -2.26; P ≤ 0.0001), in patients with severe COVID-19 compared with controls with nonsevere COVID-19 (MD -4.84 ng/mL; 95% CI, -7.32 to -2.35; P = 0.0001) and in nonsurvivors compared with survivors (MD -4.80 ng/mL; 95% CI, -7.89 to -1.71; P = 0.002). The association between vitamin D deficiency/insufficiency and death was insignificant when studies with high risk of bias or studies reporting unadjusted effect estimates were excluded. Risk of bias and heterogeneity were high across all analyses. Discrepancies in timing of vitamin D testing, definitions of severe COVID-19, and vitamin D deficiency/insufficiency partly explained the heterogeneity. Four RCTs were widely heterogeneous precluding meta-analysis.

CONCLUSION

Multiple observational studies involving nearly 2 million adults suggest vitamin D deficiency/insufficiency increases susceptibility to COVID-19 and severe COVID-19, although with a high risk of bias and heterogeneity. Association with mortality was less robust. Heterogeneity in RCTs precluded their meta-analysis.

Association between 25-hydroxyvitamin D levels and COVID-19 severity

Background and aims

Despite reports on the impact of vitamin D status on coronavirus disease 2019 (COVID-19) severity, the association between low vitamin D status and severe COVID-19 remains unclear. Moreover, researchers have not determined the aforementioned association in Japanese patients. This study aimed to investigate the association between 25-hydroxyvitamin D [25(OH)D] levels and COVID-19 severity in Japanese patients.

Methods

This retrospective observational study included 117 consecutive patients with COVID-19 admitted to the Kobe City Medical Center General Hospital between October 01, 2020, and January 31, 2021. We measured the serum 25(OH)D levels using blood specimens collected within 5 days of hospital admission using liquid chromatography-tandem mass spectrometry.

Results

There were 21 (17.9%), 73 (62.4%), 19 (16.2%) and 4 (3.4%) patients with severe deficiency (<10 ng/mL), deficiency (10–<20 ng/mL), insufficiency (20–<30 ng/mL), and sufficiency (≥30 ng/mL) of vitamin D, respectively. In univariate logistic regression analyses, lower serum 25(OH)D levels [odds ratio (OR) 1.18 per 1 ng/mL decrease, 95% confidence interval (CI) 1.04–1.33, p = 0.007] were significantly associated with invasive mechanical ventilation (IMV) or death. In a multivariate logistic regression analysis, low serum 25(OH)D levels [OR 1.22 per 1 ng/mL decrease, 95% CI 1.06–1.40, p = 0.005] were significantly associated with IMV or death. The cut-off value of serum 25(OH)D levels was 10.4 ng/mL, calculated by the receiver operating characteristic curve to detect the requirement for IMV or death.

Conclusions

To the best of our knowledge, this is the first study to assess the association between vitamin D status and COVID-19 severity in Japanese patients. Low serum 25(OH)D level was detected as an independent risk factor for severe COVID-19 among Japanese patients.

Analytical, experimental and clinical aspects of total 25-hydroxyvitamin D measurement by two ligand assays are differentially biased by disease-related factors

BACKGROUND

Pathological concentrations of plasma proteins may confound the results of binding assays. We compared two routinely used total 25-hydroxyvitamin D [t-25(OH)D] methods: a chemiluminescence-immuno-(CLIA) and an electro-chemiluminescence-protein-binding-(ECLPBA) assay.

METHODS

Two sub-studies were performed: 1) In an "in vitro" study, exogenous albumin was added to pools of patients' sera with low albumin levels; and 2) In "ex vivo" studies of Cohort_1: sera of hospitalized patients with low albumin levels, and of healthy controls; and of Cohort_2: outpatients with chronic kidney disease in pre-dialysis stage, or on peritoneal dialysis and hemodialysis were investigated by the routine and LC_MS/MS methods.

RESULTS

When increasing albumin concentrations were "in vitro" added, t-25(OH)D levels were overestimated by ECLPBA, and underestimated by CLIA. In patients' sera, positive correlations were detected between t-25(OH)D-vitamin D binding protein (DBP) values by both routine methods, and between t-25(OH)D-albumin values by all three methods. Much higher t-25(OH)D was measured by LC_MS/MS in all subgroups. When altering albumin levels with constant DBP concentration, the "in vitro" experiment revealed a higher sensitivity of ECLPBA. The "ex vivo" measurements demonstrated clinically relevant differences between the routine methods.

CONCLUSION

Both routine methods are dependent of the matrix effect in hospitalized patients, which is predicted by the DBP/Albumin ratios. In hemodialysis, ECLPBA is recommended because its outcomes differ less from those of LC_MS/MS. The results of LC_MS/MS are reliable, but not routinely available. A guidance would be valuable on how levels measured by the binding methods differ from those by LC-MS/MS in various clinical conditions.

Hypocalcemia in COVID-19: Prevalence, clinical significance and therapeutic implications

COVID-19 extra-pulmonary features include several endocrine manifestations and these are becoming strongly clinically relevant in patients affected influencing disease severity and outcomes.At the beginning of COVID-19 pandemic no population data on calcium levels in patients affected were available and in April 2020 a first case of severe acute hypocalcemia in an Italian patient with SARS-CoV-2 infection was reported. Subsequently, several studies reported hypocalcemia as a highly prevalent biochemical abnormality in COVID-19 patients with a marked negative influence on disease severity, biochemical inflammation and thrombotic markers, and mortality. Also a high prevalence of vertebral fractures with worse respiratory impairment in patients affected and a widespread vitamin D deficiency have been frequently observed, suggesting an emerging "Osteo-Metabolic Phenotype" in COVID-19.To date, several potential pathophysiological factors have been hypothesized to play a role in determining hypocalcemia in COVID-19 including calcium dependent viral mechanisms of action, high prevalence of hypovitaminosis D in general population, chronic and acute malnutrition during critical illness and high levels of unbound and unsaturated fatty acids in inflammatory responses.Since hypocalcemia is a frequent biochemical finding in hospitalized COVID-19 patients possibly predicting worse outcomes and leading to acute cardiovascular and neurological complications if severe, it is reasonable to assess, monitor and, if indicated, replace calcium at first patient hospital evaluation and during hospitalization.

The prognostic role of micronutrient status and supplements in COVID-19 outcomes: A systematic review

Micronutrients constitute an adjuvant treatment for respiratory viral infections. Since there is no effective antiviral therapy for COVID-19 yet, adjuvant intervention for the survival of critically ill patients may be significant. Search of the PubMed, CINAHL and Cochrane databases was carried out to find human studies investigating the prognostic role of micronutrient status and the effects of micronutrient supplementation intervention in COVID-19 outcomes of adult patients. Patients with certain comorbidities (diabetes mellitus type 2, obesity, renal failure, liver dysfunction etc.) or pregnant women were excluded. 31 studies (27 observational studies and 4 clinical trials) spanning the years 2020-2021, pertaining to 8624 COVID-19 patients (mean age±SD, 61 ± 9 years) were included in this systematic review. Few studies provided direct evidence on the association of serum levels of vitamin D, calcium, zinc, magnesium, phosphorus and selenium to patients' survival or death. Vitamin D and calcium were the most studied micronutrients and those with a probable promising favorable impact on patients. This review highlights the importance of a balanced nutritional status for a favorable outcome in COVID-19. Micronutrients' deficiency on admission to hospital seems to be related to a high risk for ICU admission, intubation and even death. Nevertheless, evidence for intervention remains unclear.

Contributing Factors for Calcium Changes During Hospitalization in COVID-19: A Longitudinal Study

BACKGROUND

Hypocalcemia is highly prevalent in Coronavirus disease 2019 (COVID-19). There is limited evidence about the course and roles of different parameters in the occurrence of new or worsening hypocalcemia.

OBJECTIVES

This prospective longitudinal study was conducted on hospitalized COVID-19 patients in Qazvin, Iran, in 2021.

METHODS

Serum levels of calcium, albumin, parathormone (PTH), 25(OH)D (vitamin D), magnesium, and phosphate were assessed on the first day (time one), as well as fourth to sixth days (time two) of hospitalization. Paired t-test, McNemar's test, and multivariate logistic regression test were used to compare data at two times and evaluating the independent roles of different variables in the occurrence or worsening of hypocalcemia.

RESULTS

Out of a total of 123 participants, 102 patients completed the study. The mean serum calcium level significantly decreased from 8.32 ± 0.52 mg/dL to 8.02 ± 0.55 mg/dL at time two compared to time one (P < 0.001). Also, we witnessed new or worsening hypocalcemia at time two in 44 (55%) patients with normal serum calcium or mild hypocalcemia at time one (P < 0.001). The PTH level decreased from 42.17 ± 27.20 pg/mL to 31.28 ± 23.42 pg/mL (P < 0.001). The decrease in albumin and PTH levels was an independent significant factor in the occurrence or worsening of hypocalcemia at time two (OR = 1.27; 95% CI: 1.10 - 1.46; P = 0.001 for each 1 g/L decrement in albumin and OR = 1.29; 95% CI: 1.03 - 1.62; P = 0.026 for each 10 pg/mL decrement in PTH). Vitamin D deficiency or changes during hospitalization did not have a significant role in new or worsening hypocalcemia.

CONCLUSIONS

Decreased PTH secretion and hypoalbuminemia have significant roles in the occurrence of new or worsening hypocalcemia during hospitalization due to COVID-19.

Associations between predicted vitamin D status, vitamin D intake, and risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) severity

BACKGROUND

Vitamin D may have a role in immune responses to viral infections. However, data on the association between vitamin D and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) severity have been limited and inconsistent.

OBJECTIVE

We examined the associations of predicted vitamin D status and intake with risk of SARS-CoV-2 infection and COVID-19 severity.

METHODS

We used data from periodic surveys (May 2020 to March 2021) within the Nurses' Health Study II. Among 39,315 participants, 1768 reported a positive test for SARS-CoV-2 infection. Usual vitamin D intake from foods and supplements were measured using a semiquantitative, pre-pandemic food-frequency questionnaire in 2015. Predicted 25-hydroxyvitamin D [25(OH)D] concentration were calculated based on a previously validated model including dietary and supplementary vitamin D intake, UV-B, and other behavioral predictors of vitamin D status.

RESULTS

Higher predicted 25(OH)D concentrations, but not vitamin D intake, were associated with a lower risk of SARS-CoV-2 infection. Comparing participants in the highest quintile of predicted 25(OH)D concentrations with the lowest, the multivariable-adjusted OR was 0.76 (95% CI: 0.58, 0.99; P-trend = 0.04). Participants in the highest quartile of UV-B (OR: 0.76; 95% CI: 0.66, 0.87; P-trend = 0.002) and UV-A (OR: 0.76; 95% CI: 0.66, 0.88; P-trend < 0.001) also had a lower risk of SARS-CoV-2 infection compared with the lowest. High intake of vitamin D from supplements (≥400 IU/d) was associated with a lower risk of hospitalization (OR: 0.51; 95% CI: 0.29, 0.91; P-trend = 0.04).

CONCLUSIONS

Our study provides suggestive evidence on the association between higher predicted circulating 25(OH)D concentrations and a lower risk of SARS-CoV-2 infection. Greater intake of vitamin D supplements was associated with a lower risk of hospitalization. Our data also support an association between exposure to UV-B or UV-A, independently of vitamin D and SARS-CoV-2 infection, so results for predicted 25(OH)D need to be interpreted cautiously.

Evidence of SARS-CoV-2 bacteriophage potential in human gut microbiota

Background: In previous studies we have shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replicates in vitro in bacterial growth medium, that the viral replication follows bacterial growth, and it is influenced by the administration of specific antibiotics. These observations are compatible with a ‘bacteriophage-like’ behaviour of SARS-CoV-2.  Methods: We have further elaborated on these unusual findings and here we present the results of three different supplementary experiments: (1) an electron-microscope analysis of samples of  bacteria obtained from a faecal sample of a subject positive to SARS-CoV-2; (2) mass spectrometric analysis of these cultures to assess the eventual de novo synthesis of SARS-CoV-2 spike protein; (3) sequencing of SARS-CoV-2 collected from plaques obtained from two different gut microbial bacteria inoculated with supernatant from faecal microbiota of an individual positive to SARS-CoV-2. Results: Immuno-labelling with Anti-SARS-CoV-2 nucleocapsid protein antibody confirmed presence of SARS-CoV-2 both outside and inside bacteria. De novo synthesis of SARS-CoV-2 spike protein was observed, as evidence that SARS-CoV-2 RNA is translated in the bacterial cultures. In addition, phage-like plaques were spotted on faecal bacteria cultures after inoculation with supernatant from faecal microbiota of an individual positive to SARS-CoV-2. Bioinformatic analyses on the reads obtained by sequencing RNA extracted from the plaques revealed nucleic acid polymorphisms, suggesting different replication environment in the two bacterial cultures. Conclusions: Based on these results we conclude that, in addition to its well-documented interactions with eukaryotic cells, SARS-CoV-2 may act as a bacteriophage when interacting with at least two bacterial species known to be present in the human microbiota. If the hypothesis proposed, i.e., that under certain conditions SARS-CoV-2 may multiply at the expense of human gut bacteria, is further substantiated, it would drastically change the model of acting and infecting of SARS-CoV-2, and most likely that of other human pathogenic viruses.

COVID-19, Cation Dysmetabolism, Sialic Acid, CD147, ACE2, Viroporins, Hepcidin and Ferroptosis: A Possible Unifying Hypothesis

Background: iron and calcium dysmetabolism, with hyperferritinemia, hypoferremia, hypocalcemia and anemia have been documented in the majority of COVID-19 patients at later/worse stages. Furthermore, complementary to ACE2, both sialic acid (SA) molecules and CD147 proved relevant host receptors for SARS-CoV-2 entry, which explains the viral attack to multiple types of cells, including erythrocytes, endothelium and neural tissue. Several authors advocated that cell ferroptosis may be the core and final cell degenerative mechanism.

Methods: a literature research was performed in several scientific search engines, such as PubMed Central, Cochrane Library, Chemical Abstract Service. More than 500 articles were retrieved until mid-December 2021, to highlight the available evidence about the investigated issues.

Results: based on COVID-19 literature data, we have highlighted a few pathophysiological mechanisms, associated with virus-based cation dysmetabolism, multi-organ attack, mitochondria degeneration and ferroptosis. Our suggested elucidated pathological sequence is: a) spike protein subunit S1 docking with sialylated membrane glycoproteins/receptors (ACE2, CD147), and S2 subunit fusion with the lipid layer; b) cell membrane morpho-functional changes due to the consequent electro-chemical variations and viroporin action, which induce an altered ion channel function and intracellular cation accumulation; c) additional intracellular iron concentration due to a deregulated hepcidin-ferroportin axis, with higher hepcidin levels. Viral invasion may also affect erythrocytes/erythroid precursors, endothelial cells and macrophages, through SA and CD147 receptors, with relative hemoglobin and iron/calcium dysmetabolism. AB0 blood group, hemochromatosis, or environmental elements may represent possible factors which affect individual susceptibility to COVID-19.    

Conclusions: our literature analysis confirms the combined role of SA molecules, ACE2, CD147, viroporins and hepcidin in determining the cation dysmetabolism and final ferroptosis in the cells infected by SARS-CoV-2. The altered ion channels and electrochemical gradients of the cell membrane have a pivotal role in the virus entry and cell dysmetabolism, with subsequent multi-organ immune-inflammatory degeneration and erythrocyte/hemoglobin alterations.

The Association between TNF-α, IL-6, and Vitamin D Levels and COVID-19 Severity and Mortality: A Systematic Review and Meta-Analysis

BACKGROUND

An increasing number of scientific journals have proposed a connection between tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and the severity of COVID-19. Vitamin D has been discussed as a potential therapy for COVID-19 due to its immunomodulatory effects. This meta-analysis aims to determine the relationship, if any, between TNF-α, IL-6, vitamin D, and COVID-19 severity and mortality.

METHODS

The design of the study is a systematic review and meta-analysis. A literature search is performed using PubMed, Cochrane, ProQuest, and Google Scholar.

RESULTS

TNF-α insignificantly increases the risk of COVID-19 severity (adjusted odds ratio (aOR) = 1.0304; 95% CI 0.8178-1.2983; p = 0.80) but significantly increases the risk of COVID-19 mortality (crude hazard ratio (HR) = 1.0640; 95% CI 1.0259-1.1036; p = 0.0009). IL-6 significantly increases the risk of COVID-19 severity (aOR = 1.0284; 95% CI 1.0130-1.0441; p = 0.0003) and mortality (aOR = 1.0076; 95% CI 1.0004-1.0148; p = 0.04; adjusted hazard ratio (aHR) = 1.0036; 95% CI 1.0010-1.0061; p = 0.006). There is a statistically insignificant difference of the mean vitamin D levels between patients with severe COVID-19 and non-severe COVID-19 (mean difference (MD) = -5.0232; 95% CI 11.6832-1.6368; p = 0.14). A vitamin D deficiency insignificantly increases the risk of mortality of COVID-19 patients (aOR = 1.3827; 95% CI 0.7103-2.6916; p = 0.34).

CONCLUSION

IL-6 is an independent prognostic factor towards COVID-19 severity and mortality.

Lower plasma calcium associated with COVID-19, but not with disease severity: a two-centre retrospective cohort study

BACKGROUND

Previous studies indicate hypocalcaemia as a potential diagnostic and prognostic marker of corona-virus disease 2019 (COVID-19). Our aim was to investigate these relations in more detail in a large test cohort and an independent validation cohort.

METHODS

We retrospectively included 2792 COVID-19 suspected patients that presented to the emergency department (ED) of two hospitals. Plasma calcium and ionized plasma calcium levels were compared between COVID-19 positive and negative patients, and between severe and non-severe COVID-19 patients using univariate and multivariate analyses in the first hospital (N = 1363). Severe COVID-19 was defined as intensive care unit (ICU) admission or death within 28 d after admission. The results were validated by repeating the same analyses in the second hospital (N = 1429).

RESULTS

A total of 693 (24.8%) of the enrolled patients were COVID-19 positive, of whom 238 (34.3%) had severe COVID-19. In both hospitals, COVID-19 positive patients had lower plasma calcium levels than COVID-19 negative patients, regardless of correction for albumin, in univariate and multivariate analysis (Δ0.06-0.13 mmol/L, p < .001). Ionized plasma calcium concentrations, with and without correction for pH, were also lower in COVID-19 positive patients in multivariate analyses (Δ0.02-0.05 mmol/L, N = 567, p < .001). However, we did not find a significant association between COVID-19 disease severity and plasma calcium in multivariate analyses.

CONCLUSIONS

Plasma calcium concentrations were lower in COVID-19 positive than COVID-19 negative patients but we found no association with disease severity in multivariate analyses. Further understanding of plasma calcium perturbation may facilitate the development of new preventive and therapeutic modalities for the current pandemic.

Elements and COVID-19: A Comprehensive Overview of Studies on Their Blood/Urinary Levels and Supplementation with an Update on Clinical Trials

Simple Summary

COVID-19 is a disease caused by the SARS-CoV-2 coronavirus spreading mainly through person-to-person contact. It has caused millions of deaths around the world and lasting health problems in individuals who have survived the disease. This review concisely summarizes certain issues related to COVID-19 with a focus on elements and gives an update on clinical trials where some minerals will be tested/have been tested alone or in combination with drugs, vitamins, or plant extracts/herbal formulations in COVID-19 patients and in those at higher COVID-19 risk.

Abstract

The current report provides a brief overview of the clinical features, hematological/biochemical abnormalities, biomarkers, and AI-related strategies in COVID-19; presents in a nutshell the pharmacological and non-pharmacological therapeutic options; and concisely summarizes the most important aspects related to sociodemographic and behavioral factors as well as comorbidities having an impact on this disease. It also gives a brief outline of the effect of selected elements on immune response and collects data on the levels of micro-/macro-elements and toxic metals in the blood/urine of SARS-CoV-2 infected patients and on supplementation with minerals in COVID-19 subjects. Moreover, this review provides an overview of clinical trials based on the use of minerals alone or in combination with other agents that can provide effective responses toward SARS-CoV-2 infection. The knowledge compiled in this report lays the groundwork for new therapeutic treatments and further research on biomarkers that should be as informative as possible about the patient’s condition and can provide more reliable information on COVID-19 course and prognosis. The collected results point to the need for clarification of the importance of mineral supplementation in COVID-19 and the relationships of the levels of some minerals with clinical improvement.

Components of the Mediterranean Diet and Risk of COVID-19

Adherence to the traditional Mediterranean diet has been customarily assessed with the Mediterranean diet score (MDS or Trichopolou Index), with values of 0 or 1 assigned to each of the nine elements, and with the use of the sex-specific median as the cutoff. The value of persons whose consumption of the six beneficial items (ratio of monounsaturated to saturated fatty acids, vegetables, legumes, fruits and nuts, cereal, and fish) is at or above the median and is assigned a value of 1. Otherwise they receive 0 points. For detrimental elements (meats and dairy products) persons whose consumption is below the median are assigned a value of 1. An additional ninth point is assigned to moderate ethanol intake. We assessed the effect of each of the nine components of the MDS (replacing the fats ratio with olive oil, the main source of monounsaturated fats in the Mediterranean diet) on the risk of COVID-19 infection, symptomatic and severe COVID-19. From March to December 2020, 9,699 participants of the “Seguimiento Universidad de Navarra” (SUN) cohort answered a COVID-19 questionnaire. After excluding doctors and nurses, 5,194 participants were included in the main statistical analyses. Among them, we observed 382 cases of COVID-19 based on symptoms and clinical diagnosis; 167 of them with test confirmation. For the two COVID-19 definitions used, we found a significant decrease in risk for a higher adherence to the Mediterranean diet (OR = 0.64, 95% CI: 0.42–0.98, p for trend = 0.040; and OR = 0.44, 95% CI: 0.22–0.88, p for trend = 0.020, for test-diagnosed cases). A protective effect was also found for symptomatic COVID-19 (OR = 0.64, 95% CI: 0.41–1.00, p for trend = 0.050). Among the different individual food groups, only the consumption of whole dairy products showed a harmful direct association. The Mediterranean diet as a whole seems more important than each of its components in preventing the infection and symptoms of COVID-19.

Calcium Signaling Pathway Is Involved in the Shedding of ACE2 Catalytic Ectodomain: New Insights for Clinical and Therapeutic Applications of ACE2 for COVID-19

The angiotensin-converting enzyme 2 (ACE2) is a type I integral membrane that exists in two forms: the first is a transmembrane protein; the second is a soluble catalytic ectodomain of ACE2. The catalytic ectodomain of ACE2 undergoes shedding by a disintegrin and metalloproteinase domain-containing protein 17 (ADAM17), in which calmodulin mediates the calcium signaling pathway that is involved in ACE2 release, resulting in a soluble catalytic ectodomain of ACE2 that can be measured as soluble ACE2 plasma activity. The shedding of the ACE2 catalytic ectodomain plays a role in cardiac remodeling and endothelial dysfunction and is a predictor of all-cause mortality, including cardiovascular mortality. Moreover, considerable evidence supports that the ACE2 catalytic ectodomain is an essential entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Additionally, endotoxins and the pro-inflammatory cytokines interleukin (IL)-1β and tumor necrosis factor-alpha (TNFα) all enhanced soluble catalytic ectodomain ACE2 shedding from the airway epithelia, suggesting that the shedding of ACE2 may represent a mechanism by which viral entry and infection may be controlled such as some types of betacoronavirus. In this regard, ACE2 plays an important role in inflammation and thrombotic response, and its down-regulation may aggravate COVID-19 via the renin-angiotensin system, including by promoting pathological changes in lung injury. Soluble forms of ACE2 have recently been shown to inhibit SARS-CoV-2 infection. Furthermore, given that vitamin D enhanced the shedding of ACE2, some studies reported that vitamin D treatment is associated with prognosis improvement in COVID-19. This is an updated review on the evidence, clinical, and therapeutic applications of ACE2 for COVID-19.

Vitamin D Status and SARS-CoV-2 Infection and COVID-19 Clinical Outcomes

Background: Several studies suggest an association between serum 25-hydroxyvitamin D (25OHD) and the outcomes of Severe Acute Respiratory Syndrome Corona-Virus-2 (SARS-CoV-2) infection, in particular Coronavirus Disease-2019 (COVID-19) related severity and mortality. The aim of the present meta-analysis was to investigate whether vitamin D status is associated with the COVID-19 severity, defined as ARDS requiring admission to intensive care unit (ICU) or mortality (primary endpoints) and with the susceptibility to SARS-CoV-2 and COVID-19-related hospitalization (secondary endpoints). Methods: A search in PubMed, ScienceDirect, Web of Science, Google Scholar, Scopus, and preprints repositories was performed until March 31th 2021 to identify all original observational studies reporting association measures, or enough data to calculate them, between Vitamin D status (insufficiency <75, deficiency <50, or severe deficiency <25 nmol/L) and risk of SARS-CoV-2 infection, COVID-19 hospitalization, ICU admission, or death during COVID-19 hospitalization. Findings: Fifty-four studies (49 as fully-printed and 5 as pre-print publications) were included for a total of 1,403,715 individuals. The association between vitamin D status and SARS-CoV2 infection, COVID-19 related hospitalization, COVID-19 related ICU admission, and COVID-19 related mortality was reported in 17, 9, 27, and 35 studies, respectively. Severe deficiency, deficiency and insufficiency of vitamin D were all associated with ICU admission (odds ratio [OR], 95% confidence intervals [95%CIs]: 2.63, 1.45-4.77; 2.16, 1.43-3.26; 2.83, 1.74-4.61, respectively), mortality (OR, 95%CIs: 2.60, 1.93-3.49; 1.84, 1.26-2.69; 4.15, 1.76-9.77, respectively), SARS-CoV-2 infection (OR, 95%CIs: 1.68, 1.32-2.13; 1.83, 1.43-2.33; 1.49, 1.16-1.91, respectively) and COVID-19 hospitalization (OR, 95%CIs 2.51, 1.63-3.85; 2.38, 1.56-3.63; 1.82, 1.43-2.33). Considering specific subgroups (i.e., Caucasian patients, high quality studies, and studies reporting adjusted association estimates) the results of primary endpoints did not change. Interpretations: Patients with low vitamin D levels present an increased risk of ARDS requiring admission to intensive care unit (ICU) or mortality due to SARS-CoV-2 infection and a higher susceptibility to SARS-CoV-2 infection and related hospitalization.

Association of weekly or biweekly use of 50.000 IU vitamin D3 with hypervitaminosis D

Since the beginning of COVID-19 pandemic, many Iranian people are taking 50.000 IU of vitamin D3 on the weekly or biweekly bases in order to enhance their immune system function. This cross-sectional study was conducted on the patients of endocrinology clinic to compare 25(OH)D levels of weekly or biweekly consumption with the monthly users of vitamin D3 50,000 IU. The level above 100ng/ml of 25(OH)D was defined as hypervitaminosis D. Totally, 211 patients (108 and 103 patients in monthly and weekly/biweekly groups, respectively) were studied. In the subgroups of weekly and biweekly users, the rates of hypervitaminosis were 18.9% and 4.5%, respectively. In contrast, only 0.9% of monthly users had hypervitaminosis D. The highest vitamin D value of 185 ng/ml was detected in a patient who consumed 50,000 IU vitamin D3 weekly for 6 years. No hypercalcemia was detected in the patients with hypervitaminosis D.

The effect of low serum calcium level on the severity and mortality of Covid patients: A systematic review and meta-analysis

INTRODUCTION

Imbalances of various electrolytes, including calcium, are associated with the prognosis of Covid disease. This study investigated the relationship between serum calcium and clinical outcomes in patients with COVID-19.

METHOD

This study is a systematic review and meta-analysis by searching PubMed, Scopus, web of sciences until August 2021 using the keywords COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), COVID, coronavirus disease, SARS-COV-infection. 2, SARS-COV-2, COVID19, calcium, calcium isotopes, calcium radioisotopes, hypercalcemia, and hypocalcemia were performed. Heterogeneity of studies was investigated using I2 index, data were analyzed using meta-analysis (random effects model) with Comprehensive Meta-Analysis Software software.

RESULTS

Finally, 25 articles were included in the study. Clinical data from 12 articles showed that 59% (95% confidence interval [CI]: 0.49-0.68) of people with COVID-19 have hypocalcemia. The results of meta-analysis showed that hypocalcemia was significantly associated with severity of the disease (p = .002), mortality in patients with COVID-19 (odds ratio [OR] = 6.99, 95% CI: 2.71-17.99), number of hospitalization days (p < .001) and admission to the intensive care unit (OR = 5.09, 95% CI: 2.14-12.10). The results also showed that there is a direct relationship between low serum calcium levels with increasing D-dimer levels (p = .02) and decreasing lymphocyte counts (p = .007).

CONCLUSION

Based on the results of meta-analysis in people with lower calcium, mortality and complications are higher, therefore, serum calcium is a prognostic factor in determining the severity of the disease. Consequently, it is suggested that serum calcium levels should be considered in initial assessments.

COVID-19 Mortality Risk Correlates Inversely with Vitamin D3 Status, and a Mortality Rate Close to Zero Could Theoretically Be Achieved at 50 ng/mL 25(OH)D3: Results of a Systematic Review and Meta-Analysis

BACKGROUND

Much research shows that blood calcidiol (25(OH)D3) levels correlate strongly with SARS-CoV-2 infection severity. There is open discussion regarding whether low D3 is caused by the infection or if deficiency negatively affects immune defense. The aim of this study was to collect further evidence on this topic.

METHODS

Systematic literature search was performed to identify retrospective cohort as well as clinical studies on COVID-19 mortality rates versus D3 blood levels. Mortality rates from clinical studies were corrected for age, sex, and diabetes. Data were analyzed using correlation and linear regression.

RESULTS

One population study and seven clinical studies were identified, which reported D3 blood levels preinfection or on the day of hospital admission. The two independent datasets showed a negative Pearson correlation of D3 levels and mortality risk (r(17) = -0.4154, p = 0.0770/r(13) = -0.4886, p = 0.0646). For the combined data, median (IQR) D3 levels were 23.2 ng/mL (17.4-26.8), and a significant Pearson correlation was observed (r(32) = -0.3989, p = 0.0194). Regression suggested a theoretical point of zero mortality at approximately 50 ng/mL D3.

CONCLUSIONS

The datasets provide strong evidence that low D3 is a predictor rather than just a side effect of the infection. Despite ongoing vaccinations, we recommend raising serum 25(OH)D levels to above 50 ng/mL to prevent or mitigate new outbreaks due to escape mutations or decreasing antibody activity.

Hypophosphatemia at Admission is Associated with Increased Mortality in COVID-19 Patients

Background

Electrolyte disturbances are commonly observed in patients with coronavirus disease 2019 (COVID-19) and associated with outcome in these patients. Our study was designed to examine whether hypophosphatemia is associated with mortality in COVID-19 patients.

Methods

Patients diagnosed with COVID-19 and hospitalized in Renmin Hospital of Wuhan University between January 30 and February 24, 2020 were included in this study. Patients were divided into two groups, a hypophosphatemia group and a non-hypophosphatemia group, based on a serum phosphate level of 0.8 mmol/L. Logistic regression was performed to analyze the relationship between hypophosphatemia and mortality. A locally weighted scatterplot smoothing (LOWESS) curve was plotted to show the detailed association between mortality rate and serum phosphate level. A Kaplan–Meier survival curve was drawn to compare the difference in cumulative survival between the two groups.

Results

Hypophosphatemia at admission occurred in 33 patients, with an incidence of 7.6%. The hypophosphatemia group had a significantly higher incidence of respiratory failure (54.5% vs 32.6%, p=0.013) and mortality (57.6% vs 15.2%, p<0.001). Multivariate logistic regression indicated that age (OR=1.059, p<0.001), oxygen saturation (OR=0.733, p<0.001), white blood cells (OR=1.428, p<0.001), lymphocytes (OR=0.075, p<0.001) and hypophosphatemia (OR=3.636, p=0.015) were independently associated with mortality in the included patients. The hypophosphatemia group had significantly shorter survival than the non-hypophosphatemia group (p<0.001).

Conclusion

Hypophosphatemia at admission is associated with increased mortality in COVID-19 patients. More attention and medical care should be given to COVID-19 patients with hypophosphatemia at admission.

Vitamin D and Platelets: A Menacing Duo in COVID-19 and Potential Relation to Bone Remodeling

Global data correlate severe vitamin D deficiency with COVID-19-associated coagulopathy, further suggesting the presence of a hypercoagulable state in severe COVID-19 patients, which could promote thrombosis in the lungs and in other organs. The feedback loop between COVID-19-associated coagulopathy and vitamin D also involves platelets (PLTs), since vitamin D deficiency stimulates PLT activation and aggregation and increases fibrinolysis and thrombosis. Vitamin D and PLTs share and play specific roles not only in coagulation and thrombosis but also during inflammation, endothelial dysfunction, and immune response. Additionally, another ‘fil rouge’ between vitamin D and PLTs is represented by their role in mineral metabolism and bone health, since vitamin D deficiency, low PLT count, and altered PLT-related parameters are linked to abnormal bone remodeling in certain pathological conditions, such as osteoporosis (OP). Hence, it is possible to speculate that severe COVID-19 patients are characterized by the presence of several predisposing factors to bone fragility and OP that may be monitored to avoid potential complications. Here, we hypothesize different pervasive actions of vitamin D and PLT association in COVID-19, also allowing for potential preliminary information on bone health status during COVID-19 infection.

Cardiac biomarkers and COVID-19: A systematic review and meta-analysis

OBJECTIVE

To systematically investigate the relationship between cardiac biomarkers and COVID-19 severity and mortality.

METHODS

We performed a literature search using PubMed, Web of Science, and Google Scholar. The standardized mean difference (SMD) and 95% confidence interval (CI) were applied to estimate the combined results of 67 studies. A meta-analysis of cardiac biomarkers was used to evaluate disease mortality and severity in COVID-19 patients.

RESULTS

A meta-analysis of 7812 patients revealed that patients with high levels of cardiac troponin I (SMD = 0.81 U/L, 95% CI = 0.14-1.48, P = 0.017), cardiac troponin T (SMD = 0.78 U/L, 95% CI = 0.07-1.49, P = 0.032), high-sensitive cardiac troponin I (SMD = 0.66 pg/mL, 95% CI = 0.51-0.81, P < 0.001), high-sensitive cardiac troponin T (SMD = 0.93 U/L, 95% CI = 0.21-1.65, P = 0.012), creatine kinase-MB (SMD = 0.54 U/L, 95% CI = 0.39-0.69, P < 0.001), and myoglobin (SMD = 0.80 U/L, 95% CI = 0.57-1.03, P < 0.001) were associated with prominent disease severity in COVID-19 infection. Moreover, 9532 patients with a higher serum level of cardiac troponin I (SMD = 0.51 U/L, 95% CI = 0.37-0.64, P < 0.001), high-sensitive cardiac troponin (SMD = 0.51 ng/L, 95% CI = 0.29-0.73, P < 0.001), high-sensitive cardiac troponin I (SMD = 0.51 pg/mL, 95% CI = 0.38-0.63, P < 0.001), high-sensitive cardiac troponin T (SMD = 0.85 U/L, 95% CI = 0.63-1.07, P < 0.001), creatine kinase-MB (SMD = 0.48 U/L, 95% CI = 0.32-0.65, P < 0.001), and myoglobin (SMD = 0.55 U/L, 95% CI = 0.45-0.65, P < 0.001) exhibited a prominent level of mortality from COVID-19 infection.

CONCLUSION

Cardiac biomarkers (cardiac troponin I, cardiac troponin T, high-sensitive cardiac troponin, high-sensitive cardiac troponin I, high-sensitive cardiac troponin T, creatine kinase-MB, and myoglobin) should be more frequently applied in identifying high-risk COVID-19 patients so that timely treatment can be implemented to reduce severity and mortality in COVID-19 patients.

Association of 25-Hydroxyvitamin D Level with COVID-19-Related in-Hospital Mortality: A Retrospective Cohort Study

BACKGROUND

The primary aim of this study was to compare the 25(OH)D level between patients with COVID-19 and the reference population. The secondary aim was to determine the association of 25(OH)D level with COVID-19-related in-hospital mortality.

METHODS

The COVID-19-positive group comprised 520 hospitalized patients and the reference population comprised 15,789 COVID-19-negative patients. The 25(OH)D level was categorized as vitamin D deficiency (25[OH]D < 20 ng/mL) and severe vitamin D deficiency (25[OH]D < 12 ng/mL).

RESULTS

While the incidence of vitamin D deficiency was similar in both groups, the incidence of severe vitamin D deficiency was higher in patients with COVID-19 than in the reference population (68.3% [n = 355] vs. 55.1% [n = 8,692], p < 0.001). Severe vitamin D deficiency in patients with COVID-19 was higher in the intensive care unit (ICU) group than in the non-ICU group (75.3% [n = 183] vs. 62% [n = 172], p = 0.001). The incidence of severe vitamin D deficiency was 65.4% (n = 280) in survivors and 81.5% (n = 75) in nonsurvivors (p = 0.003). However, multivariable Cox proportional hazard regression analysis showed no relationship between 25(OH)D level and in-hospital mortality. The median survival times of patients with and without severe vitamin D deficiency were not different, as shown by Kaplan-Meier survival analysis.

CONCLUSION

Severe vitamin D deficiency is more common in patients with COVID-19 and may play a significant role in worsening the prognosis of these patients. However, the 25(OH)D level was not observed to effect COVID-19-related in-hospital mortality.

Vitamin D deficiency as a predictor of severity in patients with COVID-19 infection

BACKGROUND

As an immune modulator, vitamin D has been implicated in the coronavirus disease 2019 (COVID-19) severity. This study aimed to investigate the association between vitamin D levels and the severity of COVID-19 infection.

METHODS

A cross-sectional study, which included 124 patients diagnosed with COVID-19 and were selected from Ain Shams University Hospitals and assigned to two groups; mild and severe COVID-19. All patients underwent detailed history taking, clinical data, and different laboratory investigations as complete blood count, blood urea nitrogen, serum creatinine, liver enzymes, C-reactive protein, D-dimer, ferritin and serum vitamin D concentration. In addition to findings of initial chest computed tomography (CT) were recorded. COVID-19 Reporting and Data System (CO-RADS) and CT chest severity scores (CT SS) were reported.

RESULTS

In this study of 124 COVID-19-positive individuals, a high prevalence of hypovitaminosis D was found (97.6%). Lower vitamin D levels were significantly associated with more severe COVID-19 cases (p-value < 0.001), higher blood levels of inflammatory markers including (D-dimer, CRP, and ferritin), a higher CT SS and longer disease duration. Serum vitamin D can be used as a predictor for the severity of COVID-19 infection with a specificity of 96.6%, and sensitivity of 45.5%.

CONCLUSION

The high frequency of hypovitaminosis D in severe COVID-19 patients provides further evidence of a potential link to poor prognosis and severity of the disease, so vitamin D deficiency may be a marker of poor prognosis in these patients.

Prevalence of vitamin D deficiency and its prognostic impact on patients hospitalized with COVID-19

Objectives: Although hypovitaminosis D appears to be highly prevalent in patients with coronavirus disease 2019 (COVID-19), its impact on their prognosis remains unclear.

Methods: In this study, serum 25-hydroxyvitamin D (Vit-D) level was measured in 200 patients hospitalized with COVID-19. The association between Vit-D and the composite endpoint of intensive care unit (ICU) admission/in-hospital death was explored using univariable and multivariable analyses. Also, serum Vit-D level in patients with COVID-19 was compared with that in age- and sex-balanced COVID-19-negative controls (i.e., 50 inpatients with sepsis).

Results: Serum Vit-D level was comparable between patients with COVID-19 and COVID-19-negative inpatients with sepsis (P = 0.397). No significant differences were found in serum Vit-D level according to COVID-19 severity at the time of hospital admission (P = 0.299). Incidence rates of the composite endpoint of ICU admission/in-hospital death did not differ significantly between patients with either Vit-D deficiency (i.e., Vit-D <20 ng/mL) or severe Vit-D deficiency (i.e., Vit-D <12 ng/mL) and those without (31% vs 35% with P = 0.649, and 34% vs 30% with P = 0.593, respectively). Vit-D level and status (i.e., Vit-D deficiency and severe Vit-D deficiency) were not prospectively associated with the risk of the composite endpoint of ICU admission/in-hospital death (P > 0.05 for all Cox regression models).

Conclusions: Regardless of the potential usefulness of Vit-D measurement to guide appropriate supplementation, Vit-D does not appear to provide helpful information for the stratification of in-hospital prognosis in patients with COVID-19.

COVID-19 and the Endocrine System: A Comprehensive Review on the Theme

Background and aim. The review aimed to summarize advances in the topic of endocrine diseases and coronavirus disease 2019 (COVID-19). Methods. Scientific and institutional websites and databases were searched and data were collected and organized, when plausible, to angle the discussion toward the following clinical issues. (1) Are patients with COVID-19 at higher risk of developing acute or late-onset endocrine diseases or dysfunction? (2) May the underlying endocrine diseases or dysfunctions be considered risk factors for poor prognosis once the infection has occurred? (3) Are there defined strategies to manage endocrine diseases despite pandemic-related constraints? Herein, the authors considered only relevant and more frequently observed endocrine diseases and disorders related to the hypothalamic-pituitary region, thyroid and parathyroid glands, calcium-phosphorus homeostasis and osteoporosis, adrenal glands, and gonads. Main. Data highlight the basis of some pathophysiological mechanisms and anatomical alterations of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)-induced endocrine dysfunctions. Some conditions, such as adrenal insufficiency and cortisol excess, may be risk factors of worse clinical progression once the infection has occurred. These at-risk populations may require adequate education to avoid the SARS-CoV-2 infection and adequately manage medical therapy during the pandemic, even in emergencies. Endocrine disease management underwent a palpable restraint, especially procedures requiring obligate access to healthcare facilities for diagnostic and therapeutic purposes. Strategies of clinical triage to prioritize medical consultations, laboratory, instrumental evaluations, and digital telehealth solutions should be implemented to better deal with this probably long-term situation.

Vitamin D Metabolites and Clinical Outcome in Hospitalized COVID-19 Patients

(1) Background: Vitamin D, a well-established regulator of calcium and phosphate metabolism, also has immune-modulatory functions. An uncontrolled immune response and cytokine storm are tightly linked to fatal courses of COVID-19. The present retrospective study aimed to inves-tigate vitamin D status markers and vitamin D degradation products in a mixed cohort of 148 hospitalized COVID-19 patients with various clinical courses of COVID-19. (2) Methods: The serum concentrations of 25(OH)D₃, 25(OH)D₂, 24,25(OH)₂D₃, and 25,26(OH)₂D₃ were determined by a validated liquid-chromatography tandem mass-spectrometry method in leftover serum samples from 148 COVID-19 patients that were admitted to the University Hospital of the Medical Uni-versity of Graz between April and November 2020. Anthropometric and clinical data, as well as outcomes were obtained from the laboratory and hospital information systems. (3) Results: From the 148 patients, 34 (23%) died within 30 days after admission. The frequency of fatal outcomes did not differ between males and females. Non-survivors were significantly older than survivors, had higher peak concentrations of IL-6 and CRP, and required mechanical ventilation more frequently. The serum concentrations of all vitamin D metabolites and the vitamin D metabolite ratio (VMR) did not differ significantly between survivors and non-survivors. Additionally, the need for res-piratory support was unrelated to the serum concentrations of 25(OH)D vitamin D and the two vitamin D catabolites, as well as the VMR. (4) Conclusion: The present results do not support a relevant role of vitamin D for the course and outcome of COVID-19.

Coronavirus disease 2019, vitamin D and kidney function

PURPOSE OF REVIEW

The purpose of this review is to summarize the emerging studies analyzing the association between vitamin D and risk of COVID-19 infection and severity, as well as the early interventional studies investigating the protective effect of vitamin D supplementation against COVID-19.

RECENT FINDINGS

Studies investigating the association between vitamin D levels and risk of COVID-19 infection and risk of severe disease and mortality among those infected have yielded mixed results. Thus far, the majority of studies investigating the association between vitamin D and COVID-19 have been observational and rely on vitamin D levels obtained at the time of admission, limiting causal inference. Currently, clinical trials assessing the effects of vitamin D supplementation in individuals with COVID-19 infection are extremely limited. Randomized, interventional trials may offer more clarity on the protective effects of vitamin D against COVID-19 infection and outcomes.

SUMMARY

Decreased levels of vitamin D may amplify the inflammatory effects of COVID-19 infection, yet, data regarding the mortality benefits of vitamin D supplementation in COVID-19-infected individuals are still limited. Current observational data provides the impetus for future studies to including randomized controlled trials to determine whether vitamin D supplementation in COVID-19-infected individuals with kidney disease can improve mortality outcomes.