Vitamin D and COVID-19: Role of ACE2, age, gender, and ethnicity

COVID-19 and our understanding of vitamin D and immune function

The interaction between vitamin D and the immune system is perhaps the most well recognised extraskeletal facet of vitamin D, encompassing early studies of therapy for TB and leprosy through to more recent links with autoimmune disease. However, the spotlight on vitamin D and immune function has been particularly intense in the last five years following the COVID-19 pandemic. This was due, in part, to the many association studies of vitamin D status and COVID-19 infection and disease prognosis, as well as the smaller number of clinical trials of vitamin D supplementation. However, a potential role for vitamin D in COVID-19 also stemmed from the basic biology of vitamin D that provides a plausible mechanistic rationale for beneficial effects of vitamin D for improved immune health in the setting of respiratory infection. The aim of this review is to summarise the different strands of mechanistic evidence supporting a beneficial effect of vitamin D in COVID-19, how this was modified during the pandemic itself, and the potential new aspects of vitamin D and immune function that are likely to arise in the near future. Key topics that feature in this review are: antibacterial versus antiviral innate immune responses to 1,25-dihydroxyvitamin D (1,25(OH)2D); the function of immune 1α-hydroxylase (CYP27B1) activity and metabolism of 25-hydroxyvitamin D (25(OH)D) beyond antigen-presenting cells; advances in immune cell target gene responses to 1,25-dihydroxyvitamin D (notably changes in metabolic profile). Whilst much of the interest during the COVID-19 era has focused on vitamin D and public health, the continued evolution of our understanding of how vitamin D interacts with different components of the immune system continues to support a beneficial role for vitamin D in immune health.

Proteomics Reveals That Vitamin D Deficiency Leads to Immunoglobulin Abnormalities and Immune Dysregulation in Patients with Post-COVID-19 Condition

Vitamin D (VD) levels are closely related to the occurrence of post-COVID-19 conditions (PCCs), but the specific mechanism is still unclear. Here, a total of 50 PCC patient serum samples were divided into the VD sufficient group (VD ≥ 30 ng/mL), the VD insufficient group (20 ng/mL ≤ VD < 30 ng/mL), and the VD deficiency group (VD < 20 ng/mL) and then subjected to proteomic analysis. We identified 15 differential abundance proteins (DAPs) between the VD sufficient and VD insufficient groups, including 5 immunoglobulin proteins (JCHAJN, IGHV4-28, GHV4-34, IGHM, and IGLV2-11), which were significantly negatively correlated with VD levels in PCC patients. These DAPs were primarily enriched in immune-related pathways such as the TNF signaling pathway and the B cell receptor signaling pathway. Compared with the VD insufficient group, VD deficiency resulted in 4 proteins being upregulated and 8 proteins being downregulated. The declined abundance of IGLV1-47 negatively correlated with serum VD levels. Albumin (ALB) was in the center of the protein-protein interaction (PPI) network map of all DAPs and was negatively correlated with serum VD levels. In conclusion, VD insufficiency/deficiency leads to abnormalities in immunoglobulin heavy, light, and J chains, resulting in PCC syndrome. VD supplementation may be a potential therapeutic strategy to alleviate the symptoms of PCC.

Retrospective Clinical Investigation into the Association Between Abnormal Blood Clotting, Oral Anticoagulant Therapy, and Medium-Term Mortality in a Cohort of COVID-19 Patients

Background/Objectives: People affected by COVID-19 are exposed to abnormal clotting and endothelial dysfunction, which may trigger thromboembolic events. This study aimed at retrospectively investigating whether oral anticoagulant therapy (OAT), encompassing either direct oral anticoagulants (DOACs), mainly apixaban, or the vitamin K antagonist (VKA) warfarin, could have impacted medium-term mortality in a cohort of SARS-CoV-2 patients. Methods: Among 1238 COVID-19 patients, hospitalized from 17 March 2020 to 15 June 2021, 247 survivors and 247 deceased within 90 days from hospitalization were matched 1:1 based on age, sex, and intensive care unit (ICU) admission within three days. Conditional logistic regression was used to estimate associations by means of odds ratio (OR) with a 95% confidence interval (CI). Results: A univariate regression analysis suggested that OAT, no differently from subcutaneous low-molecular-weight heparins (LMWHs) during hospitalization, has no significant impact (p value > 0.05) on medium-term mortality. A multivariate analysis, limited to baseline variables (i.e., comorbidities and pharmacotherapies at hospital admission) showing significant association (p < 0.05) to mortality in a univariate analysis, revealed that, compared to patients living at 90 days from hospitalization, deceased patients had cancer histories (OR 1.75, CI 1.06-2.90, p = 0.029) or suffered from asthma (OR 2.25, CI 1.13-4.47, p = 0.021). In contrast, heart failure (HF), atrial fibrillation (AF), arteriopathy, chronic obstructive pulmonary disease (COPD), and kidney failure (KF), which, in a univariate analysis, were found to be associated with the endpoint (p < 0.05), lost significance in a multivariate analysis. Therapy at admission with aldosterone antagonists also appeared to be associated with medium-term mortality (OR 2.49, CI 1.52-4.08, p < 0.001); whereas, vitamin D supplementation during hospitalization appeared to be beneficial. Although not conclusive, a search into the Eudravigilance database, combined with consulting a digital predictive platform (PLATO, polypharmacology platform prediction), suggested potential off-target activities, which might contribute to increasing the severity of SARS-CoV-2 infection. Conclusions: This retrospective clinical study furnished evidences of the impact of OAT, comorbidities and other pharmacological treatments on COVID-19 clinical course.

Determination of oxidative stress and copeptin levels of COVID-19 according to the clinical course

OBJECTIVE

COVID-19, caused by the novel coronavirus SARS-CoV-2, is characterized by hyperinflammation, which can trigger oxidative stress. At the same time, COVID-19 is accompanied by both psychological and physical stress. Copeptin, a novel stress marker, has been shown to predict disease outcomes in stress-induced diseases. In this study, we aimed to explore the potential of copeptin, with inflammatory and oxidative stress markers, in distinguishing between different clinical courses of COVID-19.

MATERIALS AND METHODS

This case-control study included 75 participants: 25 COVID-19 patients hospitalized in the intensive care unit (ICU), 25 non-ICU COVID-19 patients, and 25 healthy individuals. 64 % of the ICU patients received corticosteroid treatment for 4-10 days before sampling. Serum concentrations of the study parameters were assessed by enzyme-linked immunosorbent assay (ELISA) and compared between the study groups.

RESULTS

Serum IL-6 levels (p < 0.001) were significantly higher in ICU patients compared to non-ICU patients and the control group. Serum MDA (p < 0.001) and 4-HNE (p = 0.027) concentrations were significantly lower in the ICU group in comparison with the other groups. Copeptin was not statistically significant. MDA (p = 0.040) and 4-HNE (p = 0.017) levels were significantly lower in the treated ICU group than the untreated one.

CONCLUSIONS

Serum IL-6 levels were noticeably associated with COVID-19 severity. Corticosteroid therapy administration seemed to influence MDA and 4-HNE levels in the treated group, with no obvious influence on IL-6 and copeptin in the same cohort. This data suggests that in SARS-CoV-2 infection, corticosteroids may act through a rapid non-genomic mechanism.

Role of Glial Cells and Receptors in Schizophrenia Pathogenesis

The specific pathogeneses of schizophrenia (SCZ) remain an enigma despite extensive research that has implicated both genetic and environmental factors. Recent revelations that dysregulated immune system caused by glial cell overactivation result in neuroinflammation, a key player in neurodegenerative as well as neuropsychiatric disorders including SCZ are providing novel clues on potential therapeutic interventions. Here, we review the roles of glial cells (Dr. Arne Schousboe's passion) and two of their most implicated receptors, toll-like receptors (TLRs), and nicotinic cholinergic receptors, in SCZ pathology with suggestions as potential targets in this devastating neuropsychiatric condition.

Impact of Vitamin D Levels on Clinical Outcomes in SARS-CoV-2 Infections

BACKGROUND AND AIM

Since its emergence in 2019, SARS-CoV-2 has caused the global COVID-19 pandemic, presenting significant challenges for healthcare systems worldwide. Extensive research has focused on diagnostics, treatments, and vaccine development to combat the virus. Given the need for effective strategies to reduce infection rates, disease progression, and severity, this study aimed to investigate the potential role of vitamin D (25OHD) in mitigating the severity of COVID-19.

METHODS

A cross-sectional study was conducted to evaluate the relationship between serum vitamin D levels and the severity of COVID-19 symptoms. Vitamin D levels were measured using the Roche Diagnostics Vitamin D assay in 100 SARS-CoV-2-infected patients confirmed by real-time polymerase chain reaction (PCR). Patients were categorized as symptomatic or asymptomatic, and the correlation between vitamin D levels and symptom severity was analyzed.

RESULTS

The findings demonstrated that a significant proportion of symptomatic patients had vitamin D levels below 20 ng/mL. In contrast, approximately 25% of asymptomatic patients had vitamin D levels exceeding 30 ng/mL. Statistical analysis confirmed a significant association between low vitamin D levels and increased symptom severity (p=0.007).

CONCLUSION

This study suggests that vitamin D deficiency may contribute to the severity of COVID-19 symptoms. Vitamin D supplementation could potentially reduce the risk of severe disease. However, to confirm these findings and support these recommendations, further research, including randomized controlled trials and large-scale population studies, is necessary.

Effect of vitamin D status and vitamin D supplementation on immune function and prevention of acute respiratory tract infections in dark-skinned individuals: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis examined the evidence for a potential relationship between vitamin D status and vitamin D supplementation on immune function biomarkers and prevention of acute respiratory tract infections (ARTI) in dark-skinned individuals.

DESIGN

Six databases were searched (inception to December 2021) for randomised controlled trials (RCT) and observational studies. A narrative synthesis and random-effects meta-analysis were used to synthesise the findings.

SETTING

Not applicable.

PARTICIPANTS

Ethnic groups other than white, with or without a white comparator.

RESULTS

After duplicates were removed, 2077 articles were identified for screening. A total of eighteen studies (n 36 707), including seven RCT and 11 observational studies, met the inclusion criteria, and three RCT (n 5778) provided sufficient data of high enough quality to be included in a meta-analysis. An inverse association between vitamin D status and at least one inflammatory biomarker in black adults was found in three studies, and vitamin D status was inversely associated with ARTI incidence in black and Indigenous groups in two studies. There was no significant effect of vitamin D supplementation on differences in ARTI incidence in ethnic minority groups (OR, 1·40; 95 % CI: 0·70, 2·79; P = 0·34), nor African American (OR, 1·77; 95 % CI: 0·51, 6·19; P = 0·37) or Asian/Pacific (OR, 1·08; 95 % CI: 0·77, 2·68; P = 0·66) subgroups.

CONCLUSIONS

There is a lack of conclusive evidence supporting an association between vitamin D status and immune function or ARTI incidence in dark-skinned individuals. Further RCT in diverse ethnic populations are urgently needed.

Unveiling the Interplay-Vitamin D and ACE-2 Molecular Interactions in Mitigating Complications and Deaths from SARS-CoV-2

The interaction of the SARS-CoV-2 spike protein with membrane-bound angiotensin-converting enzyme-2 (ACE-2) receptors in epithelial cells facilitates viral entry into human cells. Despite this, ACE-2 exerts significant protective effects against coronaviruses by neutralizing viruses in circulation and mitigating inflammation. While SARS-CoV-2 reduces ACE-2 expression, vitamin D increases it, counteracting the virus's harmful effects. Vitamin D's beneficial actions are mediated through complex molecular mechanisms involving innate and adaptive immune systems. Meanwhile, vitamin D status [25(OH)D concentration] is inversely correlated with severity, complications, and mortality rates from COVID-19. This study explores mechanisms through which vitamin D inhibits SARS-CoV-2 replication, including the suppression of transcription enzymes, reduced inflammation and oxidative stress, and increased expression of neutralizing antibodies and antimicrobial peptides. Both hypovitaminosis D and SARS-CoV-2 elevate renin levels, the rate-limiting step in the renin-angiotensin-aldosterone system (RAS); it increases ACE-1 but reduces ACE-2 expression. This imbalance leads to elevated levels of the pro-inflammatory, pro-coagulatory, and vasoconstricting peptide angiotensin-II (Ang-II), leading to widespread inflammation. It also causes increased membrane permeability, allowing fluid and viruses to infiltrate soft tissues, lungs, and the vascular system. In contrast, sufficient vitamin D levels suppress renin expression, reducing RAS activity, lowering ACE-1, and increasing ACE-2 levels. ACE-2 cleaves Ang-II to generate Ang(1-7), a vasodilatory, anti-inflammatory, and anti-thrombotic peptide that mitigates oxidative stress and counteracts the harmful effects of SARS-CoV-2. Excess ACE-2 molecules spill into the bloodstream as soluble receptors, neutralizing and facilitating the destruction of the virus. These combined mechanisms reduce viral replication, load, and spread. Hence, vitamin D facilitates rapid recovery and minimizes transmission to others. Overall, vitamin D enhances the immune response and counteracts the pathological effects of SARS-CoV-2. Additionally, data suggests that widely used anti-hypertensive agents-angiotensin receptor blockers and ACE inhibitors-may lessen the adverse impacts of SARS-CoV-2, although they are less potent than vitamin D.

Short-Term Outcomes in Patients With Coexistence of COVID-19 Infection and Vitamin D Deficiency: A Large Cohort Study

INTRODUCTION

Vitamin D deficiency (VDD) is prevalent worldwide and may influence the severity of infectious diseases, including COVID-19. This study aimed to evaluate the association between VDD and 30-day clinical outcomes in patients with COVID-19.

METHODS

We conducted a retrospective cohort study using data from the TriNetX database, which includes de-identified electronic health records of approximately 155 million patients from 131 healthcare organizations globally. Adult patients (aged ≥18 years) with their first documented COVID-19 infection between January 2022 and September 2024 were included. Patients were categorized based on their vitamin D status within three months prior to COVID-19 diagnosis: those with documented VDD (VDD group) and those without (controls). Outcomes assessed were all-cause mortality, all-cause hospitalization, the requirement for critical care services, and a composite outcome of these events at 30-day follow-up. Propensity score matching (PSM) was utilized to balance covariates such as age, sex, race, and comorbidities between the groups. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using Cox regression analysis.

RESULTS

After PSM, the study included 68,814 patients, with 34,407 in both the VDD and control groups. VDD was associated with a slight but statistically significant increase in the hazard of experiencing the composite outcome (HR 1.05, 95% CI 1.01-1.10, P = 0.02). There was no significant difference in all-cause mortality (HR 1.06, 95% CI 0.92-1.22, P = 0.42) or all-cause hospitalization (HR 1.01, 95% CI 0.96-1.05, P = 0.80) between the groups. However, patients with VDD had a significantly higher hazard of requiring critical care services compared to controls (HR 1.28, 95% CI 1.16-1.41, P < 0.01).

CONCLUSION

Vitamin D deficiency is associated with an increased risk of requiring critical care services among COVID-19 patients, suggesting that VDD may contribute to greater disease severity. These findings underscore the potential importance of assessing and managing vitamin D deficiency in patients with COVID-19 to improve clinical outcomes.

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

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

Association between vitamin D deficiency and post-acute outcomes of SARS-CoV-2 infection

OBJECTIVES

This study aimed to investigate the association between vitamin D deficiency (VDD) and post-acute outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

METHODS

This retrospective study used the TriNetX research network to identify COVID-19 patients between January 1 and November 30, 2022. Patients were matched using propensity score matching (PSM) and divided into VDD (< 20 ng/mL) and control (≥ 20 ng/mL) groups. The primary outcome was a composite of post-COVID-19 condition (identified by ICD-10 code), all-cause emergency department (ED) visits, hospitalization, and death during the follow-up period (90-180 days) after the diagnosis of COVID-19.

RESULTS

From an initial recruitment of 42,674 non-hospitalized patients with COVID-19 and known 25(OH)D status, a VDD group of 8300 was identified and propensity matched with 8300 controls. During the follow-up period, the VDD group had a higher risk of the primary outcome than did the control group [hazard ratio (HR) = 1.122; 95% confidence interval (CI) = 1.041-1.210]. The VDD group also had a higher risk of all-cause ED visits (HR = 1.114; 95% CI = 1.012-1.226), all-cause hospitalization (HR = 1.230; 95% CI = 1.105-1.369), and all-cause death (HR = 1.748; 95% CI = 1.047-2.290) but not post-COVID-19 condition (HR = 0.980; 95% CI = 0.630-1.523), individually.

CONCLUSION

Among the COVID-19 patients, VDD might be associated with a higher risk of all-cause ED visits, hospitalization, and death during the post-acute phase.

Neutralizing Antibodies against SARS-CoV-2: Importance of Comorbidities in Health Personnel against Reinfections

One of the priority lines of action to contain the SARS-CoV-2 pandemic was vaccination programs for healthcare workers. However, with the emergence of highly contagious strains, such as the Omicron variant, it was necessary to know the serological status of health personnel to make decisions for the application of reinforcements. The aim of this work was to determine the seroprevalence against SARS-CoV-2 in healthcare workers in a Mexican hospital after six months of the administration of the Pfizer-BioNTech vaccine (two doses, 4 weeks apart) and to investigate the association between comorbidities, response to the vaccine, and reinfections. Neutralizing antibodies against SARS-CoV-2 were determined using ELISA assays for 262 employees of Hospital Juárez de México with and without a history of COVID-19. A beta regression analysis was performed to study the associated comorbidities and their relationship with the levels of antibodies against SARS-CoV-2. Finally, an epidemiological follow-up was carried out to detect reinfections in this population. A significant difference in SARS-CoV-2 seroprevalence was observed in workers with a history of COVID-19 prior to vaccination compared to those without a history of the disease (MD: 0.961 and SD: 0.049; <0.001). Beta regression showed that workers with a history of COVID-19 have greater protection compared to those without a history of the infection. Neutralizing antibodies were found to be decreased in alcoholic and diabetic subjects (80.1%). Notably, eight cases of Omicron reinfections were identified, and gender and obesity were associated with the presence of reinfections (6.41 OR; 95% BCa CI: 1.15, 105.0). The response to the vaccine was influenced by the history of SARS-CoV-2 infection and associated comorbidities. The above highlights the importance of prioritizing this segment of the population for reinforcements in periods of less than one year to guarantee their effectiveness against new variants.

Multi-omic analysis characterizes molecular susceptibility of receptors to SARS-CoV-2 spike protein

In the post COVID-19 era, new SARS-CoV-2 variant strains may continue emerging and long COVID is poised to be another public health challenge. Deciphering the molecular susceptibility of receptors to SARS-CoV-2 spike protein is critical for understanding the immune responses in COVID-19 and the rationale of multi-organ injuries. Currently, such systematic exploration remains limited. Here, we conduct multi-omic analysis of protein binding affinities, transcriptomic expressions, and single-cell atlases to characterize the molecular susceptibility of receptors to SARS-CoV-2 spike protein. Initial affinity analysis explains the domination of delta and omicron variants and demonstrates the strongest affinities between BSG (CD147) receptor and most variants. Further transcriptomic data analysis on 4100 experimental samples and single-cell atlases of 1.4 million cells suggest the potential involvement of BSG in multi-organ injuries and long COVID, and explain the high prevalence of COVID-19 in elders as well as the different risks for patients with underlying diseases. Correlation analysis validated moderate associations between BSG and viral RNA abundance in multiple cell types. Moreover, similar patterns were observed in primates and validated in proteomic expressions. Overall, our findings implicate important therapeutic targets for the development of receptor-specific vaccines and drugs for COVID-19.

Healthcare Costs and Healthcare Utilization Outcomes of Vitamin D3 Supplementation at 5000 IU Daily during a 10.9 Month Observation Period within a Pragmatic Randomized Clinical Trial

Vitamin D insufficiency has been linked to multiple conditions including bone disease, respiratory disease, cardiovascular disease, diabetes, and cancer. Observational studies indicate lower healthcare costs and healthcare utilization with sufficient vitamin D levels. The secondary aims of our previously published pragmatic clinical trial of vitamin D3 supplementation were comparisons of healthcare costs and healthcare utilization. Comparisons were made between the vitamin D3 at 5000 IU supplementation group and a non-supplemented control group. Costs of care between the groups differed but were not statistically significant. Vitamin D3 supplementation reduced healthcare utilization in four major categories: hospitalizations for any reason (rate difference: -0.19 per 1000 person-days, 95%-CI: -0.21 to -0.17 per 1000 person-days, p < 0.0001); ICU admissions for any reason (rate difference: -0.06 per 1000 person-days, 95%-CI: -0.08 to -0.04 per 1000 person-days, p < 0.0001); emergency room visits for any reason (rate difference: -0.26 per 1000 person-days, 95%-CI: -0.46 to -0.05 per 1000 person-days, p = 0.0131; and hospitalizations due to COVID-19 (rate difference: -8.47 × 10-3 per 1000 person-days, 95%-CI: -0.02 to -1.05 × 10-3 per 1000 person-days, p = 0.0253). Appropriately powered studies of longer duration are recommended for replication of these utilization findings and analysis of cost differences.

Neuroimmunological Effect of Vitamin D on Neuropsychiatric Long COVID Syndrome: A Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the coronavirus disease 2019 (COVID-19). COVID-19 is now recognized as a multiorgan disease with a broad spectrum of manifestations. A substantial proportion of individuals who have recovered from COVID-19 are experiencing persistent, prolonged, and often incapacitating sequelae, collectively referred to as long COVID. To date, definitive diagnostic criteria for long COVID diagnosis remain elusive. An emerging public health threat is neuropsychiatric long COVID, encompassing a broad range of manifestations, such as sleep disturbance, anxiety, depression, brain fog, and fatigue. Although the precise mechanisms underlying the neuropsychiatric complications of long COVID are presently not fully elucidated, neural cytolytic effects, neuroinflammation, cerebral microvascular compromise, breakdown of the blood-brain barrier (BBB), thrombosis, hypoxia, neurotransmitter dysregulation, and provoked neurodegeneration are pathophysiologically linked to long-term neuropsychiatric consequences, in addition to systemic hyperinflammation and maladaptation of the renin-angiotensin-aldosterone system. Vitamin D, a fat-soluble secosteroid, is a potent immunomodulatory hormone with potential beneficial effects on anti-inflammatory responses, neuroprotection, monoamine neurotransmission, BBB integrity, vasculometabolic functions, gut microbiota, and telomere stability in different phases of SARS-CoV-2 infection, acting through both genomic and nongenomic pathways. Here, we provide an up-to-date review of the potential mechanisms and pathophysiology of neuropsychiatric long COVID syndrome and the plausible neurological contributions of vitamin D in mitigating the effects of long COVID.

Essentials to Improve the Effectiveness of Healthy Aging Programming: Consideration of Social Determinants and Utilization of a Theoretical Model

Older adult health, while partially determined by genetics, is mostly determined by behavioral and lifestyle choices. Researchers and interventionists develop and administer behavioral health interventions with older adults, and interventions are advertised in any number of settings, for example, by providers in healthcare settings and by activity directors in senior centers or assisted living facilities. However, previous studies and metanalyses indicate that many interventions targeting older adults are unsuccessful in recruitment or in retention. While providers and activity directors may assume older adults are unwilling to participate in behavioral change, in reality, low participation may be caused by erroneous design and administration. The objective of this manuscript is to recommend to creators and implementers of behavioral interventions for older adults that they focus on two critical considerations: the contextual perspective pertaining to healthy aging as well as an appropriately employed theoretical model that most effectively informs program design and implementation. In this commentary, we discuss how Prochaska and DiClemente's Transtheoretical Model of Health Behavior Change may lead to more desirable outcomes as it considers that a person may be at any one of six stages of change, from pre-contemplation to maintenance. Currently, many behavioral interventions are targeted at individuals who are poised for action or in maintenance phases, ignoring those in earlier phases, resulting in limited overall success. Regarding viewing healthy aging in a contextual manner, determinants external to the individual may remain unnoted and unconsidered when designing or recruiting for a behavioral intervention. In conclusion, the integration of an intrapersonal health behavior model such as the Transtheoretical Model of Health Behavior Change, coupled with clearer considerations of the interplay of contextual factors operating in the lives of older adults, may allow for more effective design and implementation, as well as resulting in higher participation in behavioral interventions targeted toward older adults.

Low vitamin D levels predict outcomes of COVID-19 in patients with both severe and non-severe disease at hospitalization

PURPOSE

Low vitamin D in COVID-19 have been related to worse outcomes. However, most of the studies conducted so far were not-controlled and retrospective, including biases potentially influencing this association. We evaluated 25(OH)vitamin D levels of patients with both severe and non-severe disease at hospital-admission, and in a cohort of control subjects. Moreover, we evaluated sACE-2 levels to investigate the mechanisms underlying the association between vitamin D and COVID-19.

METHODS

COVID-19 patients were enrolled in a matched for age, sex and comorbidities 1:1-ratio based on the presence/or not of respiratory-distress/severe-disease at hospital-admission. Control matched subjects were enrolled from an outpatient-setting.

RESULTS

Seventy-three COVID-19 patients (36 severe and 37 non-severe) and 30 control subjects were included. We observed a higher vitamin D deficiency (<20 ng/mL) prevalence in COVID-19 patients than control subjects (75% vs 43%). No differences were found regarding 25(OH)vitamin D and sACE-2 levels between patients with and without severe-disease at study entry. During the disease-course, in the severe group a life-threatening disease occurred in 17 patients (47.2%), and, in the non-severe group, a worsening disease occurred in 10 (27%). 25(OH)vitamin D levels, at admission, were negatively correlated with sACE-2 levels, and were lower in patients whose disease worsened as compared to those in whom it did not, independently from the disease severity at admission. In multivariate-analysis, lower 25(OH)vitamin D resulted as an independent risk factor for disease worsening.

CONCLUSIONS

25(OH)vitamin D levels at hospital-admission strongly predicted the occurrence of worsening outcomes in COVID-19 independently of the disease severity at presentation.

The association between vitamin D intake with inflammatory and biochemical indices and mortality in critically ill patients with COVID-19: A case-control study

BACKGROUND

The coronavirus disease-2019 (COVID-19) has become a worldwide health issue with widespread hospitalization and dependence on the intensive care unit (ICU). Vitamin D has a key role in modulating immune cells and modulating the inflammatory responses. This study aimed to investigate the association of vitamin D supplementation with inflammatory, biochemical, and mortality indices in critically ill patients with COVID-19.

METHODS

This case-control study was conducted on critically ill COVID-19 patients hospitalized in the ICU including the survived >30 day patients as the case group and dead patients as the control group. The status of vitamin D supplementation and inflammatory and biochemical indices of the patients were retrieved from the medical records. Logistic regression method was used to assess the association between 30 days survival and vitamin D supplement intake.

RESULTS

Compared to the group of COVID-19 patients who died in <30 day, the survived patients had a lower eosinophile level (2.2 ± 0.5 vs. 6 ± 0.0, p < .001) and higher vitamin D supplementation duration (9 ± 4.4 vs. 3.3 ± 1.9 day, p = .001). Vitamin D supplementation had a positive association with survival in COVID-19 patients (OR: 1.98, 95% CI: 1.15-3.40, p < .05). The association remained significant after adjustments fot age, sex, underlying diseases, and smoking.

CONCLUSION

Vitamin D supplementation in critically ill patients with COVID-19 has the potential to increase survivability within the first 30 days of hospitalization.

Interaction of Vitamin D with Peptide Hormones with Emphasis on Parathyroid Hormone, FGF23, and the Renin-Angiotensin-Aldosterone System

The seminal discoveries that parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) are major endocrine regulators of vitamin D metabolism led to a significant improvement in our understanding of the pivotal roles of peptide hormones and small proteohormones in the crosstalk between different organs, regulating vitamin D metabolism. The interaction of vitamin D, FGF23 and PTH in the kidney is essential for maintaining mineral homeostasis. The proteohormone FGF23 is mainly secreted from osteoblasts and osteoclasts in the bone. FGF23 acts on proximal renal tubules to decrease production of the active form of vitamin D (1,25(OH)₂D) by downregulating transcription of 1α-hydroxylase (CYP27B1), and by activating transcription of the key enzyme responsible for vitamin D degradation, 24-hydroxylase (CYP24A1). Conversely, the peptide hormone PTH stimulates 1,25(OH)₂D renal production by upregulating the expression of 1α-hydroxylase and downregulating that of 24-hydroxylase. The circulating concentration of 1,25(OH)₂D is a positive regulator of FGF23 secretion in the bone, and a negative regulator of PTH secretion from the parathyroid gland, forming feedback loops between kidney and bone, and between kidney and parathyroid gland, respectively. In recent years, it has become clear that vitamin D signaling has important functions beyond mineral metabolism. Observation of seasonal variations in blood pressure and the subsequent identification of vitamin D receptor (VDR) and 1α-hydroxylase in non-renal tissues such as cardiomyocytes, endothelial and smooth muscle cells, suggested that vitamin D may play a role in maintaining cardiovascular health. Indeed, observational studies in humans have found an association between vitamin D deficiency and hypertension, left ventricular hypertrophy and heart failure, and experimental studies provided strong evidence for a role of vitamin D signaling in the regulation of cardiovascular function. One of the proposed mechanisms of action of vitamin D is that it functions as a negative regulator of the renin-angiotensin-aldosterone system (RAAS). This finding established a novel link between vitamin D and RAAS that was unexplored until then. During recent years, major progress has been made towards a more complete understanding of the mechanisms by which FGF23, PTH, and RAAS regulate vitamin D metabolism, especially at the genomic level. However, there are still major gaps in our knowledge that need to be filled by future research. The purpose of this review is to highlight our current understanding of the molecular mechanisms underlying the interaction between vitamin D, FGF23, PTH, and RAAS, and to discuss the role of these mechanisms in physiology and pathophysiology.

Association of Serum Vitamin D level and COVID-19 infection: A Case-control Study

BACKGROUND

Vitamin D is considered a potent modulator of the immune system, albeit its role in COVID-19 infection is a matter of debate. The present study aimed to estimate the association between serum vitamin D levels and COVID-19 among people in Qatar.

METHODS

This case-control study, approved by the Institutional Review Board of Primary Health Care Corporation (PHCC) Qatar, retrospectively evaluated the principal public healthcare sector population data repository retrieved from the cloud-based Electronic Health Record (EHR) software-Cerner, during April 2020-2021. The health records of all adult patients aged >18 years who had undergone the reverse transcription-polymerase chain reaction (RT-PCR) test and whose medical records had documented serum 25-hydroxyvitamin D [25 (OH)D] levels were analyzed.

RESULTS

A total of 924,173 EHRs were extracted, of which 62,451 EHR comprised of 16,446 (26.3%) COVID-19 patients and 46,005 (73.7%) negative-control group patients met the inclusion criteria. The odds ratio (OR) among different categories of vitamin D deficiency (VDD) revealed that people with mild/moderate VDD were 1.18 times (95% CI 1.126-1.258) and those with severe VDD were 1.90 times (95% CI 1.116-1.251) more likely to have COVID-19 infection when compared to the people with optimal serum vitamin D level. On applying multiple logistic regression, the odds of having COVID-19 infection were found to be 1.27 times (95% CI 1.184-1.371) higher among those with mild/moderate VDD and 1.32 times (95% CI 1.206-1.405) higher among those with severe VDD when compared to people with optimal vitamin D level (p < 0.001).

CONCLUSION

Our findings demonstrated a significant association between the suboptimal serum vitamin D level and COVID-19 infection. Further studies are required to determine the effects of VDD on the severity and outcomes of COVID-19 infections.

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

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

Serum vitamin D levels and COVID-19 during pregnancy: A systematic review and meta-analysis

Background

Serum vitamin D levels are reported to be associated with the risk of incidence and severity of COVID-19 in the general population. During pregnancy, immune system alterations in line with changes in vitamin D metabolism may affect the course of COVID-19. Thus, we aimed to systematically review the association between vitamin D, pregnancy, and COVID-19.

Methods

A systematic literature search was conducted in PubMed, Scopus, Web of Science, Embase, and Google Scholar until the end of May 2022. Mean differences (MD) with 95% CI were used as desired effect sizes to assess the association of serum vitamin D levels with the risk of incidence and severity of COVID-19 in pregnant women.

Results

Among 259 records, 7 and 6 studies were included in the systematic review and meta-analysis, respectively. All included studies had acceptable quality. Our results demonstrated an insignificant difference between infected women and non-infected controls (MD = -2.55 ng/ml, 95% CI: −6.85 – 1.74). But serum vitamin D levels in severe/moderate cases compared to mild ones (MD = −2.71 ng/ml, 95% CI: −4.18 to −1.24) are significantly lower.

Conclusion

Based on the current evidence, serum vitamin D level does not associate with the risk of SARS-CoV-2 infection among pregnant women, but we find a significant association with the severity of the disease. These findings may be helpful in similar conditions and future studies to better understand the complex immune alterations during pregnancy.

Recent advances in vitamin D implications in chronic respiratory diseases

Chronic airway inflammatory and infectious respiratory diseases are the most common medical respiratory conditions, associated with significant morbidity and mortality. Vitamin D (1,25(OH)₂D₃) deficiency has been shown to be highly prevalent in patients with chronic airway inflammatory and infectious diseases, correlated with increased disease severity. It has been established that vitamin D modulates ongoing abnormal immune responses in chronic respiratory diseases and is shown to restrict bacterial and viral colonization into the lungs. On the contrary, other studies revealed controversy findings regarding vitamin D efficacy in respiratory diseases. This review aims to update the current evidence regarding the role of vitamin D in airway inflammation and in various respiratory diseases. A comprehensive search of the last five years of literature was conducted using MEDLINE and non-MEDLINE PubMed databases, Ovid MEDLINE, SCOPUS-Elsevier, and data from in vitro and in vivo experiments, including clinical studies. This review highlights the importance of understanding the full range of implications that vitamin D may have on lung inflammation, infection, and disease severity in the context of chronic respiratory diseases.

Antibody dynamics post-Comirnaty and CoronaVac vaccination in Malaysia

Several vaccines have been fast-tracked through clinical trials to mitigate the progression of the SARS‑CoV‑2 pandemic. We analyzed sequential blood samples from 314 recipients of Comirnaty and CoronaVac in East Malaysia for the spike-binding IgG (IgG-S), nucleocapsid-binding IgG (IgG-N), spike-binding IgM (IgM-S) and serum vitamin D (VitD). A subset of samples was analyzed for the neutralizing antibodies (Ig-RBD). Results showed that IgG-S due to Comirnaty was significantly higher than CoronaVac. IgM-S was detected in 80.0% Comirnaty and 69.5% CoronaVac recipients, while IgG-N was detected in 58.1% CoronaVac but not in Comirnaty recipients. All IgG-S-positive vaccines possessed detectable Ig-RBD after the second dose but with a weak to moderate correlation. The serum VitD levels did not influence the antibody magnitude in both vaccines. In essence, SARS-CoV-2 vaccination is an IgG-S-dominant event, Comirnaty was more effective than CoronaVac in mounting IgG-S and Ig-RBD responses, independent of the patient’s VitD level.

Angiotensin-converting enzyme 2 rs2285666 polymorphism and clinical parameters as the determinants of COVID-19 severity in Iranian population

Host genetic factors may be correlated with the severity of coronavirus disease 2019 (COVID-19). Angiotensin-converting enzyme 2 (ACE2) plays a vital role in viral cell entrance. The current study aimed to evaluate the association of ACE2 rs2285666 polymorphism and clinical parameters with COVID-19 mortality. The ACE2 rs2285666 polymorphism was genotyped using the polymerase chain reaction-restriction fragment length polymorphism in 556 recovered and 522 dead patients. In this study, the frequency of ACE2 rs2285666 CC was significantly higher than TT genotype in dead patients. The multivariate logistic regression analysis results showed that the higher levels of alanine aminotransferase, alkaline phosphatase, creatinine, erythrocyte sedimentation rate, and C-reactive protein and the low levels of uric acid, cholesterol, low density lipoprotein, 25-hydroxyvitamin D, real-time PCR Ct values, and ACE2 rs2285666 CC genotype were associated with increased mortality rates after COVID-19. In conclusion, our findings demonstrated a possible link between COVID-19 mortality, clinical parameters, and ACE2 rs2285666 CC. Further research is required to confirm these results.

Pregnancy and COVID-19: The Possible Contribution of Vitamin D

Background: Vitamin D deficiency has been associated with the severity of COVID-19. The role of vitamin D in pregnant women with COVID-19 has been poorly investigated to date. The aim of this study was to evaluate the influence of vitamin D in affecting some clinical features in pregnancy between SARS-CoV-2 positive and negative patients. Methods: Vitamin D pathway related polymorphisms and 25-hydroxyvitamin D levels were quantified in pregnant women followed from the first to the third trimester of pregnancy. Vitamin D deficiency was considered with values ≤ 30 ng/mL. Results: In total, 160 women were enrolled: 23 resulted positive for at least one SARS-CoV-2 related test (molecular swab or antibody tests). Vitamin D-associated polymorphisms were able to affect vitamin D levels in SARS-CoV-2 negative and positive subjects: remarkably, all the VDR TaqICC genotype patients were negative for SARS-CoV-2. In a sub-population (118 patients), vitamin D levels correlated with pregnancy-related factors, such as alpha-fetoprotein levels. Third-trimester vitamin D levels were lower in preterm births compared to full-term pregnancy: this trend was highlighted for SARS-CoV-2 positive patients. Conclusions: This is the first study demonstrating a role of vitamin D in affecting the clinical characteristics of pregnant women during the COVID-19 era. Further studies in larger and different cohorts of patients are required to confirm these findings.

Immunohistochemical expression of angiotensin-converting enzyme 2 in superficial and deep maxillofacial tissues: A cross-sectional study

Background and Aims

The involvement of maxillofacial tissues in SARS-CoV-2 infections ranges from mild dysgeusia to life-threatening tissue necrosis, as seen in SARS-CoV-2-associated mucormycosis. Angiotensin-converting enzyme 2 (ACE2) which functions as a receptor for SARS-CoV-2 was reported in the epithelial surfaces of the oral and nasal cavities; however, a complete understanding of the expression patterns in deep oral and maxillofacial tissues is still lacking.

Methods

The immunohistochemical expression of ACE2 was analyzed in 95 specimens from maxillofacial tissues and 10 specimens of pulmonary alveolar tissue using a semiquantitative immunohistochemical scoring procedure, taking into account all superficial and deep maxillofacial tissue cells. We also explored the associations of age, gender, and anatomical site with expression scores.

Results

ACE2 was detected in keratinized epithelia (57.34%), non-keratinized epithelia (46.51%), nasal respiratory epithelial cells (73.35%), pulmonary alveolar cells (82.54%), fibroblasts (63.69%), vascular endothelial cells (58.43%), mucous acinar cells (59.88%), serous acinar cells (79.49%), salivary duct cells (86.26%) skeletal muscle fibers (71.01%), neuron support cells (94.25%), and bone marrow cells (72.65%). Age and gender did not affect the expression levels significantly in epithelial cells (p = 0.76, and p = 0.7 respectively); however, identical cells expressed different protein levels depending on the site from which the specimens were obtained. For example, dorsal tongue epithelia expressed significantly lower ACE2 scores than alveolar epithelia (p < 0.001). A positive correlation was found between ACE2 expression in fibroblasts and epithelial cells (r = 0.378, p = 0.001), and between vascular endothelial and epithelial cells (r = 0.395, p = 0.001).

Conclusion

ACE2 is expressed by epithelial cells and subepithelial tissues including fibroblasts, vascular endothelia, skeletal muscles, peripheral nerves, and bone marrow. No correlation was detected between ACE2 expression and patient age or sex while the epithelial expression scores were correlated with stromal scores.

"Don't Look Up" Your Science-Herd Immunity or Herd Mentality?

This analysis piece will attempt to examine some of the critical pandemic-related measures implemented in the United States from an immunological perspective and pinpoint caveats that should have been considered before their implementation. I also discuss alternative measures grounded in scientific data that were not thoroughly explored and likely could have helped fight the pandemic.

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.

The association of ACE1, ACE2, TMPRSS2, IFITM3 and VDR polymorphisms with COVID-19 severity: A systematic review and meta-analysis

Genes involved in the regulation of viral recognition and its entry into a host cell have been identified as candidates for genetic association studies on COVID-19 severity. Published findings on the effects of polymorphisms within ACE1, ACE2, TMPRSS2, IFITM3 and VDR genes remained inconclusive, so we conducted a systematic review and meta-analysis in order to elucidate their potential involvement in the genetic basis underlying the severity of COVID-19 and/or an outcome of SARS-CoV-2 infection. Identification of potentially eligible studies was based on PubMed, Scopus and Web of Science database search. Relevant studies (n=29) with a total number of 8247 SARS-CoV-2-positive participants were included in qualitative synthesis, while results of 21 studies involving 5939 were pooled in meta-analysis. Minor allele I of rs1799752 located within ACE1 was identified as a protective variant against severe COVID-19, while its effect on mortality rate was opposite. Similarly, minor allele A of ACE2 polymorphism, rs2285666, was found to associate with a decreased risk of severe COVID-19 (P = 0.003, OR = 0.512, 95 % CI = 0.331-0.793). Statistical significance was also seen for the association between COVID-19 severity and rs12329760 located within TMPRSS2. Our results did not support the supposed association of rs12252 in IFITM3 and polymorphisms within VDR with disease severity. We conclude that genetic variants within ACE1, ACE2 and TMPRSS2 may be potential biomarkers of COVID-19 severity, which needs to be further confirmed in a larger set of studies.

High-dose vitamin D versus placebo to prevent complications in COVID-19 patients: Multicentre randomized controlled clinical trial

Background

The role of oral vitamin D₃ supplementation for hospitalized patients with COVID-19 remains to be determined. The study was aimed to evaluate whether vitamin D₃ supplementation could prevent respiratory worsening among hospitalized patients with COVID-19.

Methods and findings

We designed a multicentre, randomized, double-blind, sequential, placebo-controlled clinical trial. The study was conducted in 17 second and third level hospitals, located in four provinces of Argentina, from 14 August 2020 to 22 June 2021. We enrolled 218 adult patients, hospitalized in general wards with SARS-CoV-2 confirmed infection, mild-to-moderate COVID-19 and risk factors for disease progression. Participants were randomized to a single oral dose of 500 000 IU of vitamin D₃ or matching placebo. Randomization ratio was 1:1, with permuted blocks and stratified for study site, diabetes and age (≤60 vs >60 years). The primary outcome was the change in the respiratory Sepsis related Organ Failure Assessment score between baseline and the highest value recorded up to day 7. Secondary outcomes included the length of hospital stay; intensive care unit admission; and in-hospital mortality. Overall, 115 participants were assigned to vitamin D₃ and 105 to placebo (mean [SD] age, 59.1 [10.7] years; 103 [47.2%] women). There were no significant differences in the primary outcome between groups (median [IQR] 0.0 [0.0–1.0] vs 0.0 [0.0–1.0], for vitamin D₃ and placebo, respectively; p = 0.925). Median [IQR] length of hospital stay was not significantly different between vitamin D₃ group (6.0 [4.0–9.0] days) and placebo group (6.0 [4.0–10.0] days; p = 0.632). There were no significant differences for intensive care unit admissions (7.8% vs 10.7%; RR 0.73; 95% CI 0.32 to 1.70; p = 0.622), or in-hospital mortality (4.3% vs 1.9%; RR 2.24; 95% CI 0.44 to 11.29; p = 0.451). There were no significant differences in serious adverse events (vitamin D₃ = 14.8%, placebo = 11.7%).

Conclusions

Among hospitalized patients with mild-to-moderate COVID-19 and risk factors, a single high oral dose of vitamin D₃ as compared with placebo, did not prevent the respiratory worsening.

Trial registration

ClincicalTrials.gov Identifier: NCT04411446.

Interaction of Vitamin D and Corticosteroid Use in Hospitalized COVID-19 Patients: A Potential Explanation for Inconsistent Findings in the Literature

Vitamin D is an important immune-modulator with anti-inflammatory properties. While this prohormone has been studied extensively in the prevention and treatment of COVID-19, findings have been inconsistent regarding its overall benefit in patients hospitalized with COVID-19. Most studies to date have been observational in nature, not accounting for the use of corticosteroids. Furthermore, the few randomized clinical trials designed to examine the effect of vitamin D supplementation on COVID-19 outcomes have been relatively small and thus insufficiently powered to assure a balance of corticosteroid use between study arms. The current perspective addresses the interaction of vitamin D and corticosteroids as a potential explanation for the divergent results reported in the literature. Future research on vitamin D and COVID-19 will benefit by considering this interaction, especially among hospitalized patients requiring oxygen and mechanical ventilation.

Oxidative stress status and vitamin D levels of asymptomatic to mild symptomatic COVID‐19 infections during the third trimester of pregnancy: A retrospective study in Metz, France

It is believed that the subtle equilibrium between tolerance and immunity during the unique biological state of pregnancy, which is characterized by further physiological and hormonal changes, rends pregnant women more vulnerable to coronavirus disease 2019 (COVID-19). In this retrospective study, confirmed COVID-19-positive pregnant women (n = 15) during their third trimester, comprising asymptomatic (n = 7) and mild symptomatic (n = 8), and healthy pregnant controls (n = 20), were enrolled between June 1, 2020 and  June 1, 2021 from the Hospital CHR Metz-Thionville in Metz, France. Vitamin D concentrations, C-reactive protein (CRP), and oxidative stress markers including superoxide dismutase (SOD), catalase (CAT), reduced (GSH) and oxidized (GSSG) glutathione levels, hydrogen peroxide (H₂ O₂ ), and the total antioxidant capacity, measured the ferric reducing ability of plasma (FRAP), were evaluated in the serum of patients and controls. Results showed that all pregnant women (patients and controls) enrolled in this study were vitamin D deficient (<20 ng/ml). However, mild COVID-19 pregnant women were severely vitamin D deficient (<12 ng/ml), which may suggest a link between vitamin D deficiency and the symptomatology of COVID-19 illness in singleton pregnancy. No differences between the levels of CRP and the majority of the studied oxidative stress markers in COVID-19-positive pregnant women (asymptomatic and/or mildly symptomatic patients) versus COVID-19-negative pregnant women were found, suggesting the absence or a low magnitude of oxidative stress in pregnant women with COVID-19. This may also explain the absence of severe courses of COVID-19 infection. More studies are warranted to investigate the role of vitamin D supplementation and antioxidant-rich diets in the prevention against severe forms of COVID-19 in pregnant women.

COVID-19 pneumonia patients with 25(OH)D levels lower than 12 ng/ml are at increased risk of death

Objectives

There is no consensus on specific serum 25-hydroxy vitamin D (25(OH) D) levels associated with higher risk of severe outcome in patients with coronavirus disease 2019 (COVID-19). According to the literature patients with serum 25(OH) D levels <12 ng/ml are clearly deficient at all ages. Our aim was to assess COVID-19 mortality in the settings of severe 25(OH) D deficiency. A cohort study of 357 patients with COVID-19 was conducted. Subjects were monitored until discharge or in-hospital death. At admission, severity parameters (C-reactive protein (CRP), IL-6, Charlson comorbidity index, etc.) were assessed. These parameters were compared regarding 25(OH) D levels threshold 12 ng/ml, where values below 12 ng/ml were considered absolute vitamin D deficiency.

Results

25(OH) D levels at the time of admission were independently associated with mortality (p <0.05). Nonsurvivors (N = 168) had lower 25(OH) D levels, SO2, higher age, CRP, viral load, and Charlson comorbidity index in comparison to survivors. Patients with serum 25(OH) D levels <12 ng/ml had higher mortality (55% vs 45 %), viral load (21.5 vs 23.1), and Charlson comorbidity index (5.3 vs 4.4) than those with serum 25(OH) D levels >12 ng/ml (p <0.05).

Conclusions

Patients with COVID-19 with serum 25(OH) D levels <12 ng/ml have higher mortality. Among other factors, severe vitamin D deficiency likely leads to poor outcome.

Mediterranean Diet a Potential Strategy against SARS-CoV-2 Infection: A Narrative Review

Mediterranean Diet represents the traditional eating habits of populations living around the Mediterranean Sea, and it is associated with a lower risk of overall mortality and cancer incidence and cardiovascular diseases. Severe acute respiratory syndrome coronavirus 2 is a new pandemic, and represents a significant and critical threat to global human health. In this study, we aimed to review the possible effects of Mediterranean Diet against the risk of the coronavirus disease 2019. Several vitamins, minerals, fatty acids, and phytochemicals with their potential anti-COVID-19 activity are presented. Different risk factors may increase or reduce the probability of contracting the disease. Mediterranean Diet has also a positive action on inflammation and immune system and could have a protective effect against severe acute respiratory syndrome coronavirus 2. Further studies are needed to corroborate the benefits of the Mediterranean Diet protective role on infection with SARS-CoV-2.

COVID-19, what could sepsis, severe acute pancreatitis, gender differences, and aging teach us?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a potentially life-threatening disease, defined as Coronavirus Disease 19 (COVID-19). The most common signs and symptoms of this pathological condition include cough, fever, shortness of breath, and sudden onset of anosmia, ageusia, or dysgeusia. The course of COVID-19 is mild or moderate in more than 80% of cases, but it is severe or critical in about 14% and 5% of infected subjects respectively, with a significant risk of mortality. SARS-CoV-2 related infection is characterized by some pathogenetic events, resembling those detectable in other pathological conditions, such as sepsis and severe acute pancreatitis. All these syndromes are characterized by some similar features, including the coexistence of an exuberant inflammatory- as well as an anti-inflammatory-response with immune depression. Based on current knowledge concerning the onset and the development of acute pancreatitis and sepsis, we have considered these syndromes as a very interesting paradigm for improving our understanding of pathogenetic events detectable in patients with COVID-19. The aim of our review is: 1)to examine the pathogenetic mechanisms acting during the emergence of inflammatory and anti-inflammatory processes in human pathology; 2)to examine inflammatory and anti-inflammatory events in sepsis, acute pancreatitis, and SARS-CoV-2 infection and clinical manifestations detectable in patients suffering from these syndromes also according to the age and gender of these individuals; as well as to analyze the possible common and different features among these pathological conditions; 3)to obtain insights into our knowledge concerning COVID-19 pathogenesis. This approach may improve the management of patients suffering from this disease and it may suggest more effective diagnostic approaches and schedules of therapy, depending on the different phases and/or on the severity of SARS-CoV-2 infection.

Age-related cognitive decline in rats is sex and context dependent

Previously, we had observed age-related cognitive decline in male rats compared to adolescent and adult rats. This was shown in both a multi-branched maze test (MBM), as well as in the Morris water maze test (MWM). In the present study, we compared the behavior of similar age groups in both male and female rats using the same paradigms. The results confirmed the increase in errors and time spent in MBM in aged male rats compared to other age groups. However, no such differences were observed in female rats. In the acquisition phase of MWM, aged male rats did not differ significantly from the other two groups in terms of time spent in quadrants, whereas aged female rats spent significantly more time in quadrants compared to the other 2 age groups. Aged male rats also travelled significantly more than the other 2 age groups during the acquisition phase, whereas no such differences were observed in female rats. In both short term (30 min post acquisition) and long term (24 h after acquisition) retrieval phases of MWM, significant gender-related differences were also observed in all age groups. These findings suggest gender- and context-dependent alterations in cognitive functions during aging.

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.

Lower serum 25(OH)D levels associated with higher risk of COVID-19 infection in U.S. Black women

Objective

Limited evidence suggests that higher levels of serum vitamin D (25(OH)D) protect against SARS-CoV-2 virus (COVID-19) infection. Black women commonly experience 25(OH)D insufficiency and are overrepresented among COVID-19 cases. We conducted a prospective analysis of serum 25(OH)D levels in relation to COVID-19 infection among participants in the Black Women’s Health Study.

Methods

Since 1995, the Black Women’s Health Study has followed 59,000 U.S. Black women through biennial mailed or online questionnaires. Over 13,000 study participants provided a blood sample in 2013–2017. 25(OH)D assays were performed in a certified national laboratory shortly after collection of the samples. In 2020, participants who had completed the online version of the 2019 biennial health questionnaire were invited to complete a supplemental online questionnaire assessing their experiences related to the COVID-19 pandemic, including whether they had been tested for COVID-19 infection and the result of the test. We used logistic regression analysis to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association of 25(OH)D level with COVID-19 positivity, adjusting for age, number of people living in the household, neighborhood socioeconomic status, and other potential confounders.

Results

Among 5,081 eligible participants whose blood sample had been assayed for 25(OH)D, 1,974 reported having had a COVID-19 test in 2020. Relative to women with 25(OH)D levels of 30 ng/mL (75 nmol/l) or more, multivariable-adjusted ORs for COVID-19 infection in women with levels of 20–29 ng/mL (50–72.5 nmol/l) and <20 ng/mL (<50 nmol/l) were, respectively, 1.48 (95% CI 0.95–2.30) and 1.69 (95% CI 1.04–2.72) (p trend 0.02).

Conclusion

The present results suggest that U.S. Black women with lower levels of 25(OH)D are at increased risk of infection with COVID-19. Further work is needed to confirm these findings and determine the optimal level of 25(OH)D for a beneficial effect.

Just a Reflection: Does Drug Repurposing Perpetuate Sex-Gender Bias in the Safety Profile?

Vaccines constitute a strategy to reduce the burden of COVID-19, but the treatment of COVID-19 is still a challenge. The lack of approved drugs for severe COVID-19 makes repurposing or repositioning of approved drugs a relevant approach because it occurs at lower costs and in a shorter time. Most preclinical and clinical tests, including safety and pharmacokinetic profiles, were already performed. However, infective and inflammatory diseases such as COVID-19 are linked with hypoalbuminemia and downregulation of both phase I and phase II drug-metabolizing enzymes and transporters, which can occur in modifications of pharmacokinetics and consequentially of safety profiles. This appears to occur in a sex- and gender-specific way because of the sex and gender differences present in the immune system and inflammation, which, in turn, reflect on pharmacokinetic parameters. Therefore, to make better decisions about drug dosage regimens and to increases the safety profile in patients suffering from infective and inflammatory diseases such as COVID-19, it is urgently needed to study repurposing or repositioning drugs in men and in women paying attention to pharmacokinetics, especially for those drugs that are previously scarcely evaluated in women.