Relationship between serum vitamin D concentrations and clinical outcome of community-acquired pneumonia

Increased susceptibility to complicated pneumonia among egyptian children with FokI (rs2228570), not TaqI (rs731236), vitamin D receptor gene polymorphism in association with vitamin D deficiency: a case-control study

BACKGROUND

Determining a genetic contribution to the development of complicated community-acquired pneumonia in children may help understand underlying pathogenesis. We aimed to investigate the association between two vitamin D receptor (VDR) gene polymorphisms, FokI and TaqI, and susceptibility to complicated pneumonia in Egyptian children compared to uncomplicated pneumonia. Associations with 25 hydroxy-vitamin D serum level were studied.

METHODS

This was a case-control study that included 320 participants divided into 2 groups: patients and controls. The patients' group included 100 children hospitalized with complicated pneumonia and 100 with uncomplicated pneumonia. 120 age and sex-matched apparently healthy children served as controls. The VDR FokI and TaqI polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. 25 hydroxy-vitamin D level was estimated in serum using ELISA.

RESULTS

Regarding FokI, homozygous CC genotype was more common in complicated (52%) than uncomplicated pneumonia (28%) and controls (10%) (OR = 65; 95%CI (5.13-822.63), p < 0.001) and (OR = 4.3; 95%CI (0.7-27.16), p = 0.003), respectively. Children carrying C allele possessed 3 higher odds for complicated than uncomplicated pneumonia (OR = 3.08; 95%CI (1.33-7.14), p < 0.001). Heterozygous CT genotype increased susceptibility to complicated pneumonia (OR = 13.7; 95%CI (4.6-40.1), p < 0.001), not uncomplicated pneumonia (OR = 1.56; 95%CI (0.86-2.85), p = 0.145). Among complicated pneumonia, vitamin D level was lower in CC (6.92 ± 2.6ng/ml) than CT (9.55 ± 3.2 ng/ml) and TT genotype carriers (13.13 ± 3.6ng/ml) (p < 0.001). There was no significant difference between patients and controls as regards TaqI genotypes and alleles.

CONCLUSION

In association with vitamin D deficiency, VDR gene FokI polymorphism, not TaqI, is a genetic risk factor for complicated pneumonia in Egyptian children.

Prevalence of vitamin D deficiency and associated risk of all-cause and cause-specific mortality among middle-aged and older adults in the United States

Introduction

The prevalence of vitamin D deficiency varied among populations and regions worldwide. In addition, the association between vitamin D deficiency and health outcomes remained controversial. Our study aimed to investigate the prevalence of vitamin D deficiency and its association with mortality risk among non-institutional middle-aged and older adults in the United States.

Method

The study population included 11,119 adult participants aged between 50 and 79 years in the 2007-2016 National Health and Nutrition Examination Survey (NHANES). Vitamin D status was divided as ≤ 30 (severely deficient), 30.1-50 (moderately deficient), 50.1-75 (insufficient), 75.1-100 (sufficient), and > 100 nmol/L (very sufficient). NHANES data were linked to National Death Index to ascertain the survival status and cause of death.

Results

The population aged 61.5 years (survey-weighted) and 47.9% were men. Among them, 4.6% were severely vitamin D deficient, 15.2% moderately deficient, and 33.6% insufficient. Individuals with higher vitamin D levels tended to be female, older, white people, non-smoker, non-single, more educated, with higher family income, and lower body mass index. During a median follow-up of 97.0 months, a total of 1,585 participants died (15.9 per 10,000 person-months). The crude analysis showed that vitamin D deficiency, but not vitamin D insufficiency, correlated to higher all-cause mortality risk. The association remained similar after adjusting for potential confounders, showing that vitamin D deficiency (HR: 1.38, 95% CI 1.15-1.66), but not vitamin D insufficiency (HR: 1.03, 95% CI 0.88-1.20), correlated to higher all-cause mortality risk. In addition, we showed that vitamin D deficiency was an independent risk factor for death from pneumonia (HR: 3.82, 95% CI 1.14-12.86) but not from cardiovascular diseases, cancer, or cerebrovascular diseases.

Conclusion

In summary, among middle-aged and older adults in the United States, nearly 20% were vitamin D deficient. Vitamin D deficiency, but not vitamin D insufficiency, correlated to increased mortality risk.

Investigation of Vitamin a and 25(OH)D3 Levels in Cattle with Pneumonia Detected Mycoplasma bovis

This study investigated the presence of Mycoplasma bovis in nasal swabs taken from cattle with pneumonia, to reveal the clinical and biochemical findings of positive animals, and determine the levels of vitamin A and 25(OH)D3. In the study were included 103 infected cattle and 10 healthy cattle, all aged 1-4 years, as the control group. Quantitative clinical evaluations and clinical examinations were performed on each animal, and 5 ml blood samples and nasal swabs were taken. Serum biochemistry, vitamin A and 25(OH)D3 levels were determined in both positive and control samples. The clinical signs were identified by qualitative scoring in M. bovis positive animals. Regarding the clinical findings, respiratory frequency, heart rate, and rectal temperature were significantly higher in positive than control group animals (p<0.001). Regarding the biochemistry findings, albumin (ALB) and glucose (GLU) levels were lower in cattle infected with M. bovis (p<0.001) whereas total protein (TP) and alkaline phosphatase (ALP) levels were higher (p<0.001). While serum 25(OH)D3 levels were lower in infected animals (p<0.001), there was no significant difference (p>0.05) in serum vitamin A levels. In this study, clinical findings in cattle naturally infected with M. bovis were expressed qualitatively and quantitatively. In addition, it has been revealed that the disease does not only cause lung involvement, but also causes changes in biochemical and vitamin levels. Although these parameters cannot be used as a biomarker in the diagnosis of pneumonia, they are thought to provide benefits in terms of diagnosis, treatment and prophylaxis in practice.

A novel LC-MS/MS method for the simultaneous analysis of selected fat-soluble vitamins in serum obtained from pediatric patients with pneumonia

Several observational studies have reported associations between low levels of fat-soluble vitamins (A, D and E) and the incidence of pneumonia. Whether infection affects or negatively regulates serum vitamin levels remains controversial. Our aims were to develop and validate a simple-pretreatment and fast method to determine the serum levels of selected fat-soluble vitamins, namely vitamin A (retinol), vitamin D (25-OH-D₃, 25-OH-D₂, and 3-epi-25-OH-D₃), and vitamin E (α-tocopherol), in children suffering from pneumonia during the acute phase and after inflammatory marker recovery. The sample preparation procedure involving protein precipitation and filtration was finished in one step, and separation took 8 min per sample. The calibrations were linear, with R² > 0.99. Both the intra-run (n = 6) and inter-run (n = 3) precision (relative standard deviation, RSD%) values were below 14.61%. The spiked recoveries at 3 concentrations ranged from 80.97 to 111.91%. Accuracies were calibrated using both National Institute of Standards and Technology serum (NIST 968f) and external quality assurance (EQA) samples offered by the National Center of Clinical Laboratories of China, and the relative error (RE%) values ranged from -13.17% to 12.53%. Clinical sample analysis revealed that infection did alter the serum retinol concentration and it did not alter the 25-OH-D and α-tocopherol levels in young children with pneumonia.

The long-term prognostic value of serum 25(OH)D, albumin, and LL-37 levels in acute respiratory diseases among older adults

Background

Older adults are more susceptible to respiratory tract infection than healthy working age adults. The increased susceptibility of older adults is thought to be interlinked with vitamin D status, nourishment, and immunological state in general. Data are scarce whether these parameters could serve as prognostic markers.

Aim

To study whether serum 25(OH)D, albumin, and LL-37 level could give prognostic value of long-term survival in the older adults with multimorbidity and acute respiratory infection.

Methods

Consecutive episodes of hospital care of patients 65 years and older with respiratory symptoms were prospectively studied as a cohort. Standard clinical questionnaire was filled by the study physician. Laboratory markers included serum levels of 25(OH)D, albumin and LL-37, C-reactive protein (CRP), white blood cell count (WBC) and polymerase chain reaction diagnostics for 14 respiratory viruses. Pneumonia was confirmed by chest radiographs. Respiratory illness severity, death at ward, length of hospital stays, and 5-year survival were used as outcomes.

Results

In total, 289 older adult patients with mean age of 83 years were included in the study. Serum 25(OH)D deficiency (< 50 nmol/liter) was present in 59% and hypoalbuminemia (< 3.5 g/dL) in 55% of the study patients. Low serum albumin level was associated to one, two- and five-year mortality after hospital stay (all P < .05). In addition, it was associated with pneumonia, dyspnea, over 13-night long stay at ward and death at ward (all P < .05). No associations were seen between serum 25(OH)D and LL-37 levels and disease severity, short-term clinical outcome, or long-term survival. Associations between serum 25(OH)D, albumin, and LL-37 levels and respiratory virus presence were not seen.

Conclusions

Serum albumin level on admission seems to give valuable information about the patients’ general health and recovery potential in treating older adults with respiratory symptoms. Serum 25(OH)D and LL-37 had no associations with disease severity or long- and short-term prognosis among older adults hospitalized with respiratory symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02836-8.

Effects of 1,25-Dihydroxyvitamin D3 and 25-Hydroxyvitamin D3 on PBMCs From Dairy Cattle Naturally Infected With Mycobacterium avium subsp. paratuberculosis

The role of vitamin D₃ in modulating immune responses has been well-established for over two decades; however, its specific functions have not been extensively detailed in cattle, particularly cattle in different stages of infection with Mycobacterium avium subspecies paratuberculosis (MAP). Consistent with previous work in our lab, the present study showed that infected cattle in the clinical stage of disease have reduced serum 25-hydroxyvitamin D₃ [25(OH)D₃]. Additionally, effects of vitamin D₃ on peripheral blood mononuclear cells (PBMCs) from naturally infected dairy cattle in subclinical (n = 8) or clinical (n = 8) stages of infection were compared to non-infected control cows (n = 8). Briefly, PBMCs were isolated and cultured in vitro with 4 ng/ml 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] or 100 ng/ml 25(OH)D₃. Treatment with 1,25(OH)₂D₃ resulted in decreased secretion for some pro-inflammatory cytokines in clinical animals, including IL-1β, IL-6, and IFN-γ. Similar responses for IL-1β and IL-6 were noted with the addition of 25(OH)D₃. Additionally, pro-inflammatory cytokine gene expression tended to be upregulated in PBMCs from clinical animals after treatment with 1,25(OH)₂D₃. In contrast, PBMCs from clinical animals treated with 25(OH)D₃ showed downregulation of pro-inflammatory cytokine gene expression, although only significant for IL1B. Following 25(OH)D₃ treatment, clinical animals showed significant reduction in CD4+CD25+ T cells. CYP27B1 gene expression was notably decreased in clinical and control animals following 25(OH)D₃ treatment but increased in subclinical cows. 1,25(OH)₂D₃ treatment reduced CYP24A1 gene expression in all groups, while 25(OH)D₃ treatment only significantly reduced expression for control cows. Lastly, serum 25(OH)D₃ levels were significantly lower in clinical animals. Taken together, these data show vitamin D₃ modulates cytokine signaling in cattle at different stages of MAP infection and, therefore, may have implications on disease progression.

Evidences suggesting a possible role of Vitamin D in COVID 19: The missing link

The severe acute respiratory syndrome coronavirus 2 is spreading like wildfire with no specific recommended treatment in sight. While some risk factors such as the presence of comorbidities, old age, and ethnicity have been recognized, not a lot is known about who the virus will strike first or impact more. In this hopeless scenario, exploration of time-tested facts about viral infections, in general, seems to be a sound basis to prop further research upon. The fact that immunity and its various determinants (e.g., micronutrients, sleep, and hygiene) have a crucial role to play in the defense against invading organisms, may be a good starting point for commencing research into these as yet undisclosed territories. Herein, the excellent immunomodulatory, antiviral, and anti-inflammatory roles of Vitamin D necessitate thorough investigation, particularly in COVID-19 perspective. This article reviews mechanisms and evidence suggesting the role Vitamin D plays in people infected by the newly identified COVID-19 virus. For this review, we searched the databases of Medline, PubMed, and Embase. We studied several meta-analyses and randomized controlled trials evaluating the role of Vitamin D in influenza and other contagious viral infections. We also reviewed the circumstantial and anecdotal evidence connecting Vitamin D with COVID-19 emerging recently. Consequently, it seems logical to conclude that the immune-enhancing, antiviral, anti-inflammatory, and lung-protective role of Vitamin D can be potentially lifesaving. Hence, Vitamin D deserves exhaustive exploration through rigorously designed and controlled scientific trials. Using Vitamin D as prophylaxis and/or chemotherapeutic treatment of COVID-19 infection is an approach worth considering. In this regard, mass assessment and subsequent supplementation can be tried, especially considering the mechanistic evidence in respiratory infections, low potential for toxicity, and widespread prevalence of the deficiency of Vitamin D affecting many people worldwide.

Serum 25-hydroxyvitamin D concentrations and mortality in dogs with blastomycosis

Blastomycosis is a prominent fungal disease in the United States. Vitamin D status has been found to be altered in critical illness and various infectious diseases. The objectives of this study were to compare serum 25-hydroxyvitamin D (25[OH]D) concentrations in dogs with blastomycosis and healthy controls, to assess the change in serum 25(OH)D concentrations in dogs with blastomycosis after 30 days of treatment, and to determine if baseline serum 25(OH)D concentrations in dogs with blastomycosis were associated with in-hospital, 30-day, or end-of-study mortality. In this prospective cohort study, 19 dogs newly diagnosed with blastomycosis had serum 25(OH)D concentrations measured with a commercially available validated radioimmunoassay at the time of diagnosis and 30 days after start of treatment. These values were compared to 24 healthy control dogs. Serum 25(OH)D concentrations at the time of diagnosis were lower in dogs with blastomycosis (median, 203 nmol/L; range, 31-590 nmol/L) than in clinically healthy control dogs (259.5 nmol/L, 97-829 nmol/L; P = 0.01). Despite clinical improvement, there was no significant change in serum 25(OH)D concentrations from baseline to 30-day follow-up. Dogs with baseline serum 25(OH)D concentrations <180.5nmol/L had a greater odds of death during hospitalization (odds ratio [OR], 15.0; 95% confidence interval [CI], 1.4-191.3; P = 0.04) and at 30 days follow-up (OR, 30.0; 95% CI, 2.5-366.7; P = 0.006). These findings highlight the need for further studies evaluating the prognostic value of vitamin D status in dogs with blastomycosis at diagnosis and throughout treatment and remission.

Role of vitamin D in treating COVID-19-associated coagulopathy: problems and perspectives

Aggressive inflammatory response leading to hypercoagulability has been found to be associated with disease severity in COVID-19 patients and portends bad treatment outcome. A state of acute disseminated intravascular coagulation (DIC), along with pulmonary embolism and/or deep vein thrombosis, has been observed in critically ill ICU patients. Autopsy reports of COVID-19 patients demonstrated microthrombi in lungs and in other organs, as well as marked inflammatory changes, characteristic clinicopathological features that exacerbate disease severity. Vitamin D supplementation was recommended by many clinicians across the globe to improve clinical symptoms of COVID-19 patients, mainly because of its immunomodulatory roles on immune cells. Furthermore, vitamin D and its associated molecules are also known to directly or indirectly regulate various thrombotic pathways. We propose that vitamin D supplementation not only attenuates the risk of Acute Respiratory Disease Syndrome (ARDS) but it also may have a role in reducing coagulation abnormalities in critically ill COVID-19 patients. The overarching goal of this review is to discuss the effects of vitamin D on coagulation pathways and other intertwined processes leading to thrombosis. Many clinical trials are currently investigating the efficacy of vitamin D supplementation in reducing the risk of COVID-19 infection. However, randomized placebo control clinical trials are also necessary to ascertain the effect of vitamin D supplementation on reducing the risk of coagulopathy in COVID-19 patients.

Vitamin D and Immune Regulation: Antibacterial, Antiviral, Anti-Inflammatory

Regulation of immune function continues to be one of the most well-recognized extraskeletal actions of vitamin D. This stemmed initially from the discovery that antigen presenting cells such as macrophages could actively metabolize precursor 25-hydroxyvitamin D (25D) to active 1,25-dihydroxyvitamin D (1,25D). Parallel observation that activated cells from the immune system expressed the intracellular vitamin D receptor (VDR) for 1,25D suggested a potential role for vitamin D as a localized endogenous modulator of immune function. Subsequent studies have expanded our understanding of how vitamin D exerts effects on both the innate and adaptive arms of the immune system. At an innate level, intracrine synthesis of 1,25D by macrophages and dendritic cells stimulates expression of antimicrobial proteins such as cathelicidin, as well as lowering intracellular iron concentrations via suppression of hepcidin. By potently enhancing autophagy, 1,25D may also play an important role in combatting intracellular pathogens such as M. tuberculosis and viral infections. Local synthesis of 1,25D by macrophages and dendritic cells also appears to play a pivotal role in mediating T-cell responses to vitamin D, leading to suppression of inflammatory T helper (Th)1 and Th17 cells, and concomitant induction of immunotolerogenic T-regulatory responses. The aim of this review is to provide an update on our current understanding of these prominent immune actions of vitamin D, as well as highlighting new, less well-recognized immune effects of vitamin D. The review also aims to place this mechanistic basis for the link between vitamin D and immunity with studies in vivo that have explored a role for vitamin D supplementation as a strategy for improved immune health. This has gained prominence in recent months with the global coronavirus disease 2019 health crisis and highlights important new objectives for future studies of vitamin D and immune function. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

COVID-19 Disease and Vitamin D: A Mini-Review

Novel coronavirus disease (COVID-19) pandemic caused by SARS-CoV-2, for which there is no effective treatment except employing prevention strategies, has already instituted significant number of deaths. In this review, we provide a scientific view on the potential role of vitamin D in SARS-CoV-2 virus/COVID-19 disease. Vitamin D is well-known to play a significant role in maintaining the immune health of an individual. Moreover, it induces antimicrobial peptide expression that can decrease viral replication and regulate the levels of pro-inflammatory/anti-inflammatory cytokines. Therefore, supplementation of vitamin D has the potential to reduce the incidence, severity and the risk of death from pneumonia resulting from the cytokine storm of many viral infections including COVID-19. We suggest that supplementation of subjects at high risk of COVID-19 with vitamin D (1.000 to 3.000 IU) to maintain its optimum serum concentrations may be of significant benefit for both in the prevention and treatment of the COVID-19.

Association Between Vitamin D Deficiency and COVID-19 Incidence, Complications, and Mortality in 46 Countries: An Ecological Study

Each patient's immune defenses play a major role in mitigating the impact (ie, morbidity and mortality) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). Vitamin D is an important modulator of the immune system. Although serum 25-hydroxyvitamin D levels can be raised through diet or supplements, most vitamin D in the body is the result of dermal synthesis from ultraviolet radiation. The production of vitamin D in the skin, however, can be limited by latitude, skin-covering clothes, the use of sunblock, and skin pigmentation. Vitamin D deficiency affects a high percentage of the world population. Serum 25-hydroxyvitamin D levels are suboptimal, not only in specific risk groups but also in adults from many countries. Low vitamin D levels, therefore, represent a risk factor for several different pathologies, including SAR-CoV-2. This study used an ecological design to assess the association between vitamin D deficiency and COVID-19 incidence, complications, and mortality across 46 countries. All data were obtained from published sources. The results of the study suggest an association at the population level between the prevalence of vitamin D deficiency and the risk of being infected with COVID-19, severity of the disease, and risk of dying from it.

Serum level of vitamin D as a predictor for severity and outcome of pneumonia

BACKGROUND AND AIM

of the study: Pneumonia is the most common medical illness causing hospital admissions and the most common cause of sepsis and septic shock. Vitamin D deficiency is a global health problem that affects several populations worldwide. Unfortunately, data regarding the relationship between vitamin D concentrations and outcomes of pneumonia in adult patients are sparse. Thus, we aimed to assess the prevalence of vitamin D deficiency among pneumonia patients and to correlate its levels with patients' outcomes.

PATIENTS AND METHODS

This is a prospective study of 100 patients with pneumonia admitted to Al-Azhar University hospital at New Damietta City. Data from history, Physical examination and biochemical analyses were collected. Grouping was based on vitamin D status. A comparison was made between groups regarding pneumonia severity and outcome. Also, correlation between Vit D level and outcome was studied.

RESULTS

Our study showed that 63% of patients had vitamin D level below 12 ng/mL, and patients with vitamin D level below 20 was 84%. We found an association between vitamin D deficiency and pneumonia severity. The severity of pneumonia was significantly higher among the deficient group. We also found that there was statistically significant increase of complications in deficient group. The patients improved without complications had the highest levels of vitamin D, while ARDS and septicemia complicated patients had the lowest levels of vitamin D. In addition, there was a difference between the two groups regarding to mortality. The mortality rate was higher in the deficient group as compared to non-deficient group.

CONCLUSION

Vitamin D deficiency is a common problem among critically ill patients. Its status affects pneumonia severity and outcome.

Antirheumatic drugs for COVID-19 treatment based on the phases of the disease: Current concept

COVID-19 disease is the most recent pandemic, since it has affected more than four and a half million people and caused more than 300,000 deaths. It is a very complex systemic disease in terms of pathogenesis, treatment, and prognosis. Pharmacological treatment may include antiviral and antimalarial drugs, antibiotics, monoclonal antibodies, corticosteroids as well as low-molecular-weight heparins to prevent the evolution of the disease from reaching the severe inflammatory phase that can lead to respiratory complications, multiple organ failure, disseminated intravascular coagulation (DIC), and finally death. Therefore, pending the development of the much sought-after vaccine, there needs to be a multidisciplinary approach to tackling this disease, and it is essential to use different medical treatments at the correct pathogenic moment. The aim of this article is to evaluate the rationale and reason behind the use of antirheumatic drugs, by expert point of view, in the various phases of the disease. Another important aspect in the management of the disease is to identify patients at high risk, both to change their lifestyle and to correct the state of their health through non-pharmacological measures for improving their immuno-balance. Our literature review reveals the important role and the therapeutic potential of antirheumatic agents in preventing the progression of the disease and aiding recovery from the disease. However, there is a lack of clinical evidence to support the use of these agents, indicating that further randomized controlled studies are required.

Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths

The world is in the grip of the COVID-19 pandemic. Public health measures that can reduce the risk of infection and death in addition to quarantines are desperately needed. This article reviews the roles of vitamin D in reducing the risk of respiratory tract infections, knowledge about the epidemiology of influenza and COVID-19, and how vitamin D supplementation might be a useful measure to reduce risk. Through several mechanisms, vitamin D can reduce risk of infections. Those mechanisms include inducing cathelicidins and defensins that can lower viral replication rates and reducing concentrations of pro-inflammatory cytokines that produce the inflammation that injures the lining of the lungs, leading to pneumonia, as well as increasing concentrations of anti-inflammatory cytokines. Several observational studies and clinical trials reported that vitamin D supplementation reduced the risk of influenza, whereas others did not. Evidence supporting the role of vitamin D in reducing risk of COVID-19 includes that the outbreak occurred in winter, a time when 25-hydroxyvitamin D (25(OH)D) concentrations are lowest; that the number of cases in the Southern Hemisphere near the end of summer are low; that vitamin D deficiency has been found to contribute to acute respiratory distress syndrome; and that case-fatality rates increase with age and with chronic disease comorbidity, both of which are associated with lower 25(OH)D concentration. To reduce the risk of infection, it is recommended that people at risk of influenza and/or COVID-19 consider taking 10,000 IU/d of vitamin D₃ for a few weeks to rapidly raise 25(OH)D concentrations, followed by 5000 IU/d. The goal should be to raise 25(OH)D concentrations above 40-60 ng/mL (100-150 nmol/L). For treatment of people who become infected with COVID-19, higher vitamin D₃ doses might be useful. Randomized controlled trials and large population studies should be conducted to evaluate these recommendations.

Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths

The world is in the grip of the COVID-19 pandemic. Public health measures that can reduce the risk of infection and death in addition to quarantines are desperately needed. This article reviews the roles of vitamin D in reducing the risk of respiratory tract infections, knowledge about the epidemiology of influenza and COVID-19, and how vitamin D supplementation might be a useful measure to reduce risk. Through several mechanisms, vitamin D can reduce risk of infections. Those mechanisms include inducing cathelicidins and defensins that can lower viral replication rates and reducing concentrations of pro-inflammatory cytokines that produce the inflammation that injures the lining of the lungs, leading to pneumonia, as well as increasing concentrations of anti-inflammatory cytokines. Several observational studies and clinical trials reported that vitamin D supplementation reduced the risk of influenza, whereas others did not. Evidence supporting the role of vitamin D in reducing risk of COVID-19 includes that the outbreak occurred in winter, a time when 25-hydroxyvitamin D (25(OH)D) concentrations are lowest; that the number of cases in the Southern Hemisphere near the end of summer are low; that vitamin D deficiency has been found to contribute to acute respiratory distress syndrome; and that case-fatality rates increase with age and with chronic disease comorbidity, both of which are associated with lower 25(OH)D concentration. To reduce the risk of infection, it is recommended that people at risk of influenza and/or COVID-19 consider taking 10,000 IU/d of vitamin D₃ for a few weeks to rapidly raise 25(OH)D concentrations, followed by 5000 IU/d. The goal should be to raise 25(OH)D concentrations above 40-60 ng/mL (100-150 nmol/L). For treatment of people who become infected with COVID-19, higher vitamin D₃ doses might be useful. Randomized controlled trials and large population studies should be conducted to evaluate these recommendations.

Acute Respiratory Tract Infection and 25-Hydroxyvitamin D Concentration: A Systematic Review and Meta-Analysis

Observational studies and randomised controlled studies suggest that vitamin D plays a role in the prevention of acute respiratory tract infection (ARTI); however, findings are inconsistent and the optimal serum 25-hydroxyvitamin D (25(OH)D) concentration remains unclear. To review the link between 25(OH)D concentration and ARTI, we searched PubMed and EMBASE databases to identify observational studies reporting the association between 25(OH)D concentration and risk or severity of ARTI. We used random-effects meta-analysis to pool findings across studies. Twenty-four studies were included in the review, 14 were included in the meta-analysis of ARTI risk and five in the meta-analysis of severity. Serum 25(OH)D concentration was inversely associated with risk and severity of ARTI; pooled odds ratios (95% confidence interval) were 1.83 (1.42-2.37) and 2.46 (1.65-3.66), respectively, comparing the lowest with the highest 25(OH)D category. For each 10 nmol/L decrease in 25(OH)D concentration, the odds of ARTI increased by 1.02 (0.97-1.07). This was a non-linear trend, with the sharpest increase in risk of ARTI occurring at 25(OH)D concentration < 37.5 nmol/L. In conclusion, there is an inverse non-linear association between 25(OH)D concentration and ARTI.

Effect of vitamin D deficiency in Korean patients with acute respiratory distress syndrome

BACKGROUND/AIMS

Vitamin D modulates innate and adaptive immune responses, and vitamin D deficiency is associated with increased mortality in hospitalized patients with pneumonia. We evaluated the prevalence of vitamin D deficiency in Korean patients with acute respiratory distress syndrome (ARDS) and its effect on the clinical outcomes of ARDS.

METHODS

We retrospectively analyzed the data of 108 patients who had a measured serum level of 25-hydroxy vitamin D3 (25(OH)D3) at the time of diagnosis with ARDS. The clinical outcomes were evaluated based on 25(OH)D3 levels of 20 ng/mL and stratified by quartiles of 25(OH)D3 levels.

RESULTS

The mean age of patients was 59.4 years old; 77 (71.3%) were male. Vitamin D deficiency was found in 103 patients (95.4%). The mean 25(OH)D3 level was 8.3 ± 7.0 ng/mL. Neither in-hospital mortality (40.0% vs. 68.0%) nor 6-month mortality (40.0% vs. 71.8%) significantly differed between groups. There were no significant differences in 25(OH)D3 level between survivors (8.1 ± 7.6 ng/mL) and non-survivors (8.5 ± 6.8 ng/mL, p = 0.765). There were no trends toward a difference in mortality among quartiles of 25(OH)D3 levels. However, 25(OH)D3 levels were inversely related with length of hospital stay and intensive care unit stay among in-hospital survivors.

CONCLUSION

Vitamin D deficiency was prevalent in Korean patients with ARDS. However, levels of vitamin D were not associated with mortality. A large, prospective study is needed to evaluate the effects of vitamin D deficiency on clinical outcomes of ARDS.

Effect of adjunctive single high-dose vitamin D3 on outcome of community-acquired pneumonia in hospitalised adults: The VIDCAPS randomised controlled trial

Low vitamin D status is associated with increased risk of pneumonia, greater disease severity and poorer outcome. However, no trials have examined the effect of adjunctive vitamin D therapy on outcomes in adults with community-acquired pneumonia (CAP). We conducted a randomised, double-blind, placebo-controlled trial examining the effects of adjunctive vitamin D in adults hospitalised with CAP. Participants were randomised to either a single oral dose of 200,000 IU vitamin D₃ or placebo. The primary outcome was the complete resolution of chest radiograph infiltrate at 6 weeks post-study treatment. Secondary outcomes included length of hospital stay, intensive care admission and return to normal activity. Only participants who completed the study or died within the 6 week period were included in the analysis (n = 60 vitamin D, n = 57 placebo). Adjunctive vitamin D did not have any effect on the primary outcome (OR 0.78, 95% CI 0.31 to 1.86, p = 0.548). However, there was evidence it increased the complete resolution of pneumonia in participants with baseline vitamin D levels <25 nmol/L (OR 17.0, 95% CI 1.40-549.45, P = 0.043), but this did not reach statistical significance using exact methods (OR 13.0, 95%CI 0.7-960.4, P = 0.083). There were no significant effects for any secondary outcome.

Serum 25-hydroxyvitamin D levels in hospitalized adults with community-acquired pneumonia

INTRODUCTION

Community-acquired pneumonia (CAP) is the infectious disease with the highest number of deaths worldwide. Several studies have shown an association between vitamin D deficiency and increases susceptibility to respiratory tract infections.

OBJECTIVE

The aim of this study was to evaluate the serum 25-hydroxyvitamin D (25OHD) levels in hospitalized adults in general room with CAP.

MATERIALS AND METHODS

An observational study was carried out in 207 hospitalized adults of both sex with CAP (>18 years) from Rosario city, Argentina (32° 52' 18″S) between July 2015 and June 2016.

RESULTS

In total, 167 patients were included in the data analysis [59% women (57.4 ± 19.6 years), body mass index 27.2 ± 7.8 kg/m² ]. In brief, 63% showed unilobar infiltrate and 37% were multilobar. The CURB-65 index was 66.5% low risk, 16.0% intermediate risk and 17.5% high risk. According to Charlson comorbidity index (CCI) 53.5% had not comorbidity (CCI = 0) and 46.5% showed CCI ≥ 1. The 25OHD level was: 11.92 ± 7.6 ng/mL (51.5%: <10 ng/mL, 33.5%: 10-20 ng/mL, 13.2%: 20-30 ng/mL and 1.8%: >30 ng/mL). Higher 25OHD were found in male (female: 10.8 ± 6.7 ng/mL, male: 13.5 ± 8.5 ng/mL, P = .02) and 25OHD correlated with age (r = -.17; P = .02). 25-Hydroxyvitamin D was also correlated with CURB65 index (r = -.13; P = .049), CCI (r = -.20, P = .007) and with the 10 years of life expectative (%) (r = .19; P = .008). In addition, higher 25OHD were found with lower CCI (CCI 0 = 13.0 ± 8.2 ng/mL, CCI ≥ 1= 10.5 ± 6.7 ng/mL; P = .0093).

CONCLUSIONS

Hospitalized adults with CAP have lower 25OHD levels and would be associated with the severity of CAP.

Association between serum concentration of 25-hydroxyvitamin D and community-acquired pneumonia: a case-control study

Background

Community-acquired pneumonia (CAP) is a common disease with significant morbidity and mortality. There is evidence that vitamin D deficiency can be associated with infectious diseases. The aim of this study was to compare the levels of vitamin D between patients with CAP and healthy controls.

Methods

In a case-control study on 73 patients with CAP and 76 healthy controls, the serum concentration of 25-hydroxyvitamin D (25[OH]D) was measured. Severity and outcomes of disease and also duration of hospital stay were compared in patients with different levels of 25(OH)D. The severity of CAP was assessed using the CURB-65 score (confusion, uremia, respiratory rate, low blood pressure, age ≥65 years) and was also reflected by the length of hospital stay, admission to intensive care unit (ICU), and 30-day mortality.

Results

In total, 81.2% of the study population had vitamin D levels <30 ng/dL. The risk of pneumonia among subjects with deficient vitamin D levels was 3.69 (95% CI: 1.46, 9.31) times of those with sufficient vitamin D level (P=0.006). Prevalence of severe deficiency of vitamin D in scores three and four of CURB-65 (59.38%), was far more than scores one and two (31.71%). Also, results indicated patients with severe deficiency had a higher risk for ICU admission, 30-day mortality, and longer hospitalization stay, but these were not statistically significant.

Conclusion

According to findings, a low level of 25(OH)D is associated with a higher incidence of CAP and more severe disease. It is recommended to pay more attention to vitamin D deficiency in infectious diseases, particularly in CAP patients.

Seasonal variations of U.S. mortality rates: Roles of solar ultraviolet-B doses, vitamin D, gene exp ression, and infections

Death rates in the U.S. show a pronounced seasonality. The broad seasonal variation shows about 25% higher death rates in winter than in summer with an additional few percent increase associated with the Christmas and New Year's holidays. A pronounced increase in death rates also starts in mid-September, shortly after the school year begins. The causes of death with large contributions to the observed seasonality include diseases of the circulatory system; the respiratory system; the digestive system; and endocrine, nutritional, and metabolic diseases. Researchers have identified several factors showing seasonal variation that could possibly explain the seasonal variations in mortality rate. These factors include seasonal variations in solar ultraviolet-B(UVB) doses and serum 25-hydroxyvitamin D [25(OH)D] concentrations, gene expression, ambient temperature and humidity, UVB effects on environmental pathogen load, environmental pollutants and allergens, and photoperiod (or length of day). The factors with the strongest support in this analysis are seasonal variations in solar UVB doses and 25(OH)D concentrations. In the U.S., population mean 25(OH)D concentrations range from 21ng/mL in March to 28ng/mL in August. Measures to ensure that all people had 25(OH)D concentrations >36ng/mL year round would probably reduce death rates significantly.

Vitamin D Status and Long-Term Mortality in Community-Acquired Pneumonia: Secondary Data Analysis from a Prospective Cohort

Background

Low vitamin D status has been associated with short-term (30-day) mortality in hospitalized adults with community-acquired pneumonia (CAP). Data on its prevalence in these patients are scarce, and impact on long-term prognosis is unknown. We examined the prevalence of vitamin D deficiency and inadequacy and their effect on long-term mortality in hospitalized adults with CAP.

Methods

Secondary follow-up analysis of data from a prospectively recruited (January 2008–January 2011) well-defined cohort of 241 hospital survivors of CAP (Norway, latitude 60°N). Serum 25-hydroxyvitamin D levels, demographic, clinical, and laboratory data were measured within 48 hours of admission. The etiology of CAP was established in 63% of patients through extensive microbiological investigations. Mortality data were obtained from the national Cause of Death Registry. Explanatory strategy and Cox regression models were used to explore the association between vitamin D status and all-cause mortality.

Results

Median age was 66 years. Eighty-seven (36%) patients were vitamin D deficient (<30 nmol/L), 81 (34%) were inadequate (30–49 nmol/L), and 73 (30%) were sufficient (≥50 nmol/L). Seventy-two patients died over a median of 1839 days (range 1–2520 days), corresponding to cumulative 5-year survival rates of 66.2% (95% CI 56.2–76.2%), 77.0% (67.6–86.4%), and 77.8% (67.8–87.8%) for vitamin D deficient, inadequate, and sufficient patients, respectively. After adjusting for confounders (age, chronic obstructive pulmonary disease, immunocompromization and season), vitamin D deficiency, but not inadequacy, was significantly associated with higher mortality compared to patients with sufficiency (HR 1.91, 95% CI 1.06–3.45; P = .031).

Conclusions

There is a high prevalence of vitamin D deficiency and inadequacy among hospitalized adults with CAP. The results of this study also suggest that vitamin D deficiency is associated with an increased risk of mortality way beyond the short-term in these patients.