Association between prehospital vitamin D status and incident acute respiratory failure in critically ill patients: a retrospective cohort study

Obesity, Hypovitaminosis D, and COVID-19: the Bermuda Triangle in Public Health

PURPOSE OF REVIEW

The COVID-19 pandemic has challenged public health to a significant extent by markedly increasing morbidity and mortality. Evidence suggests that obesity and hypovitaminosis D constitute important risk factors for SARS-CoV-2 infection, severity of disease, and poor outcomes. Due to their high prevalence globally, obesity and hypovitaminosis D are considered pandemics. This review presents current epidemiologic and genetic data linking obesity, hypovitaminosis D, and COVID-19, highlighting the importance of the convergence of three pandemics and their impact on public health. We also briefly summarize potential mechanisms that could explain these links.

RECENT FINDINGS

Epidemiologic data have shown that obesity is an independent risk factor for COVID-19, severe disease and death, and genetic evidence has suggested a causal association between obesity-related traits and COVID-19 susceptibility and severity. Additionally, obesity is independently associated with hypovitaminosis D, which is highly prevalent in subjects with obesity. Hypovitaminosis D is independently associated with a higher risk for COVID-19, severity, hospitalization, infectious complications, acute respiratory distress syndrome, and poor outcomes. However, genome-wide association studies have not revealed any causal association between vitamin D levels and the risk for COVID-19, while there is no robust evidence for a beneficial role of vitamin D supplementation in the prevention and treatment of COVID-19. In the context of the ongoing COVID-19 pandemic, the epidemiologic impact of obesity and hypovitaminosis D is emphasized. Efforts to increase public awareness and reinforce preventive and therapeutic measures against obesity and hypovitaminosis D are strongly required.

Positive Effects of Vitamin D Supplementation in Patients Hospitalized for COVID-19: A Randomized, Double-Blind, Placebo-Controlled Trial

Retrospective studies showed a relationship between vitamin D status and COVID-19 severity and mortality, with an inverse relation between SARS-CoV-2 positivity and circulating calcifediol levels. The objective of this pilot study was to investigate the effect of vitamin D supplementation on the length of hospital stay and clinical improvement in patients with vitamin D deficiency hospitalized with COVID-19. The study was randomized, double blind and placebo controlled. A total of 50 subjects were enrolled and received, in addition to the best available COVID therapy, either vitamin D (25,000 IU per day over 4 consecutive days, followed by 25,000 IU per week up to 6 weeks) or placebo. The length of hospital stay decreased significantly in the vitamin D group compared to the placebo group (4 days vs. 8 days; p = 0.003). At Day 7, a significantly lower percentage of patients were still hospitalized in the vitamin D group compared to the placebo group (19% vs. 54%; p = 0.0161), and none of the patients treated with vitamin D were hospitalized after 21 days compared to 14% of the patients treated with placebo. Vitamin D significantly reduced the duration of supplemental oxygen among the patients who needed it (4 days vs. 7 days in the placebo group; p = 0.012) and significantly improved the clinical recovery of the patients, as assessed by the WHO scale (p = 0.0048). In conclusion, this study demonstrated that the clinical outcome of COVID-19 patients requiring hospitalization was improved by administration of vitamin D.

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

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

Vitamin D for Recovery of COVID-19 in Patients With Chronic Kidney Disease

The severity of coronavirus disease 2019 (COVID-19) is determined not only by viral damage to cells but also by the immune reaction in the host. In addition to therapeutic interventions that target the viral infection, immunoregulation may be helpful in the management of COVID-19. Vitamin D exerts effects on both innate and adaptive immunity and subsequently modulates immune responses to bacteria and viruses. Patients with chronic kidney disease (CKD) frequently have vitamin D deficiency and increased susceptibility to infection, suggesting a potential role of vitamin D in this vulnerable population. In this paper, we review the alterations of the immune system, the risk of COVID-19 infections and mechanisms of vitamin D action in the pathogenesis of COVID-19 in CKD patients. Previous studies have shown that vitamin D deficiency can affect the outcomes of COVID-19. Supplementing vitamin D during treatment may be protective against COVID-19. Future studies, including randomized control trials, are warranted to determine the effect of vitamin D supplementation on the recovery from COVID-19 in CKD patients.

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.

Association of Vitamin D receptor gene polymorphisms and clinical/severe outcomes of COVID-19 patients

Introduction

Growing evidence documented the critical impacts of vitamin D (VD) in the prognosis of COVID-19 patients. The functions of VD are dependent on the vitamin D receptor (VDR) in the VD/VDR signaling pathway. Therefore, we aimed to assess the association of VDR gene polymorphisms with COVID-19 outcomes.

Methods

In the present study, eight VDR single nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 500 COVID-19 patients in Iran, including 160 asymptomatic, 250 mild/moderate, and 90 severe/critical cases. The association of these polymorphisms with severity, clinical outcomes, and comorbidities were evaluated through the calculation of the Odds ratio (OR).

Results

Interestingly, significant associations were disclosed for some of the SNP-related alleles and/or genotypes in one or more genetic models with different clinical data in COVID-19 patients. Significant association of VDR-SNPs with signs, symptoms, and comorbidities was as follows: ApaI with shortness of breath (P ˂ 0.001) and asthma (P = 0.034) in severe/critical patients (group III); BsmI with chronic renal disease (P = 0.010) in mild/moderate patients (group II); Tru9I with vomiting (P = 0.031), shortness of breath (P = 0.04), and hypertension (P = 0.030); FokI with fever and hypertension (P = 0.027) in severe/critical patients (group III); CDX2 with shortness of breath (P = 0.022), hypertension (P = 0.036), and diabetes (P = 0.042) in severe/critical patients (group III); EcoRV with diabetes (P ˂ 0.001 and P = 0.045 in mild/moderate patients (group II) and severe/critical patients (group III), respectively). However, the association of VDR TaqI and BglI polymorphisms with clinical symptoms and comorbidities in COVID-19 patients was not significant.

Conclusion

VDR gene polymorphisms might play critical roles in the vulnerability to infection and severity of COVID-19, probably by altering the risk of comorbidities. However, these results require further validation in larger studies with different ethnicities and geographical regions.

The role of vitamin D deficiency on COVID-19: a systematic review and meta-analysis of observational studies

OBJECTIVES

Although vaccination has started, coronavirus disease 2019 (COVID-19) poses a continuing threat to public health. Therefore, in addition to vaccination, the use of supplements to support the immune system may be important. The purpose of this study was to synthesize evidence on the possible effect of low serum vitamin D levels (25[OH]D<20 ng/mL or 50 nmol/L) on COVID-19 infection and outcomes.

METHODS

We searched Google Scholar, PubMed, Scopus, Web of Science, and ScienceDirect without any language restrictions for articles published between January 1 and December 15, 2020. We performed 3 meta-analyses (called vitamin D and COVID-19 infection meta-analysis [D-CIMA], vitamin D and COVID-19 severity meta-analysis [D-CSMA], and vitamin D and COV ID-19 mortality meta-analysis [D-CMMA] for COVID-19 infection, severity, and mortality, respectively) to combine odds ratio values according to laboratory measurement units for vitamin D and the measured serum 25(OH)D level.

RESULTS

Twenty-one eligible studies were found to be relevant to the relationship between vitamin D and COVID-19 infection/outcomes (n=205,869). The D-CIMA meta-analysis showed that individuals with low serum vitamin D levels were 1.64 times (95% confidence interval [CI], 1.32 to 2.04; p<0.001) more likely to contract COVID-19. The D-CSMA meta-analysis showed that people with serum 25(OH)D levels below 20 ng/mL or 50 nmol/L were 2.42 times (95% CI, 1.13 to 5.18; p=0.022) more likely to have severe COVID-19. The D-CMMA meta-analysis showed that low vitamin D levels had no effect on COVID-19 mortality (OR, 1.64; 95% CI, 0.53 to 5.06, p=0.390).

CONCLUSIONS

According to our results, vitamin D deficiency may increase the risk of COVID-19 infection and the likelihood of severe disease. Therefore, we recommend vitamin D supplementation to prevent COVID-19 and its negative outcomes.

Low Circulating Vitamin D in Intensive Care Unit-Admitted COVID-19 Patients as a Predictor of Negative Outcomes

BACKGROUND

Vitamin D deficiency has been associated with an increased risk of respiratory infections.

OBJECTIVES

The study aimed to evaluate the serum 25-hydroxyvitamin D [25(OH)D] concentration in patients admitted to the intensive care unit (ICU) as a predictor of coronavirus disease 2019 (COVID-19) mortality.

METHODS

A single-center retrospective observational study was conducted. Forty adult patients (50% men) with confirmed COVID-19 who were admitted to the ICU were enrolled. The primary endpoint was mortality at day 60. Serum 25(OH)D concentration was measured on the day of admission to the ICU. We used the Mann-Whitney test, Fisher's exact test, Kaplan-Meier analysis, and receiver operator characteristic (ROC) analysis to assess serum 25(OH)D concentration as a predictor of COVID-19 mortality.

RESULTS

All 40 patients had a low median (IQR) serum 25(OH)D concentration at admission [12 (9-15) ng/mL]. The median (IQR) serum 25(OH)D concentration was greater in survivors [13.3 (10.0-17.1) ng/mL, n = 22] than in nonsurvivors [9.6 (7.9-14.2) ng/mL; n = 18], P = 0.044. The area under the ROC curve was 0.69 (95% CI: 0.52, 0.86; P = 0.044). The 60-d mortality rate of those with serum 25(OH)D concentrations ≤9.9 ng/mL (n = 14, 71%) tended to be greater than that of those with concentrations >9.9 ng/mL (n = 26, 31%) (P = 0.065), and they had a 5.6-fold higher risk of death (OR: 5.63; 95% CI: 1.35, 23.45; P = 0.018).

CONCLUSIONS

The ICU patients had a low serum 25(OH)D concentration. Serum 25(OH)D concentrations ≤9.9 ng/mL on admission can be used to predict in-hospital mortality in patients with COVID-19.This trial was registered at clinicaltrials.gov as NCT04450017.

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

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

Coronavirus disease 2019, vitamin D and kidney function

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Calcifediol Treatment and Hospital Mortality Due to COVID-19: A Cohort Study

Context. Calcifediol has been proposed as a potential treatment for COVID-19 patients. Objective: To compare the administration or not of oral calcifediol on mortality risk of patients hospitalized because of COVID-19. Design: Retrospective, multicenter, open, non-randomized cohort study. Settings: Hospitalized care. Patients: Patients with laboratory-confirmed COVID-19 between 5 February and 5 May 2020 in five hospitals in the South of Spain. Intervention: Patients received calcifediol (25-hydroxyvitamin D₃) treatment (0.266 mg/capsule, 2 capsules on entry and then one capsule on day 3, 7, 14, 21, and 28) or not. Main Outcome Measure: In-hospital mortality during the first 30 days after admission. Results: A total of 537 patients were hospitalized with COVID-19 (317 males (59%), median age, 70 years), and 79 (14.7%) received calcifediol treatment. Overall, in-hospital mortality during the first 30 days was 17.5%. The OR of death for patients receiving calcifediol (mortality rate of 5%) was 0.22 (95% CI, 0.08 to 0.61) compared to patients not receiving such treatment (mortality rate of 20%; p < 0.01). Patients who received calcifediol after admission were more likely than those not receiving treatment to have comorbidity and a lower rate of CURB-65 score for pneumonia severity ≥ 3 (one point for each of confusion, urea > 7 mmol/L, respiratory rate ≥ 30/min, systolic blood pressure < 90 mm Hg or diastolic blood pressure ≤ 60 mm Hg, and age ≥ 65 years), acute respiratory distress syndrome (moderate or severe), c-reactive protein, chronic kidney disease, and blood urea nitrogen. In a multivariable logistic regression model, adjusting for confounders, there were significant differences in mortality for patients receiving calcifediol compared with patients not receiving it (OR = 0.16 (95% CI 0.03 to 0.80). Conclusion: Among patients hospitalized with COVID-19, treatment with calcifediol, compared with those not receiving calcifediol, was significantly associated with lower in-hospital mortality during the first 30 days. The observational design and sample size may limit the interpretation of these findings.

Vitamin D Status and COVID-19 Clinical Outcomes in Hospitalized Patients

Context: Populations severely affected by COVID-19 are also at risk for vitamin D deficiency. Common risk factors include older age, chronic illness, obesity, and non-Caucasian race. Vitamin D deficiency has been associated with risk for respiratory infections and failure, susceptibility and response to therapy for enveloped virus infection, and immune-mediated inflammatory reaction.Objective: To test the hypothesis that 25-hydroxyvitamin D[25(OH)D] deficiency is a risk factor for severity of COVID-19 respiratory and inflammatory complications.Design: We examined the relationship between prehospitalization 25(OH)D levels (obtained 1-365 days prior to admission) and COVID-19 clinical outcomes in 700 COVID-19 positive hospitalized patients.Primary Outcomes: Discharge status, mortality, length of stay, intubation status, renal replacement.Secondary Outcomes: Inflammatory markers.Results: 25(OH)D levels were available in 93 patients [25(OH)D:25(IQR:17-33)ng/mL]. Compared to those without 25(OH)D levels, those with measurements did not differ in age, BMI or distribution of sex and race, but were more likely to have comorbidities. Those with 25(OH)D < 20 ng/mL (n = 35) did not differ from those with 25(OH)D ≥ 20 ng/mL in terms of age, sex, race, BMI, or comorbidities. Low 25(OH)D tended to be associated with younger age and lower frequency of preexisting pulmonary disease. There were no significant between-group differences in any outcome. Results were similar in those ≥50 years, in male/female-only cohorts, and when differing 25(OH)D thresholds were used (<15 ng/mL and <30 ng/mL). There was no relationship between 25(OH)D as a continuous variable and any outcome, even after controlling for age and pulmonary disease.Conclusions: These preliminary data do not support a relationship between prehospitalization vitamin D status and COVID-19 clinical outcomes.

Covid-19 Susceptibility and Severity Might be Modified by Vitamin D Status: Theoretical and Practical Considerations

Background:

The recently identified SARS-CoV-2 coronavirus has resulted in the Covid-19 pandemic with severe morbidity and high mortality, particularly in certain sections of the population. The co-morbidity patterns associated with adverse outcomes are multiple and complex and there is emerging epidemiological, nutritional and molecular biological evidence that an inadequate vitamin D status is a contributing factor.

Objective:

The aim was to review the role of vitamin D in immune function with particular reference to the mechanisms whereby it supports immune efficiency, host protection and immune modulation. The evidence for the possible benefit of vitamin D supplementation to ameliorate the severity of respiratory infection by SARS-CoV-2 and other pathogens was also reviewed with a view to making a recommendation.

Methods:

PubMed, MEDLINE and Google Scholar were searched using the terms: Covid-19, coronavirus, SARS-CoV-2, vitamin D, calcitriol, deficiency, adaptive immunity, innate immunity, ventilation, critical care, intensive care, acute respiratory distress syndrome, cytokine storm, respiratory viruses, respiratory tract infection, respiratory syncytial virus, influenza, supplementation. Papers for inclusion were selected on the basis of relevance and quality.

Findings:

Vitamin D insufficiency is widespread in many parts of the world. Vitamin D is needed for normal protective and surveillance immune function and there is evidence that deficiency increases the risk of some respiratory infections, probably including Covid-19. By binding with dedicated receptors on immune cells vitamin D influences several strands of immune function, including the production of anti-microbial peptides and several cytokines that promote an appropriate immune response. Vitamin D supplementation probably reduces the risk of respiratory infection, with persuasive biological, epidemiological and observational evidence for possible benefit against Covid-19.

Conclusion:

Despite the lack of direct evidence specific to Covid-19 a cogent theoretical case can be made for giving adults from selected groups, and arguably all adults, routine supplementation with vitamin D to improve immune efficiency and reduce the incidence and severity of respiratory infections. This could be particularly important in sections of the population with a high prevalence of vitamin D insufficiency. Targeted research is required to provide firm evidence to guide practice.

Can Optimum Solar Radiation Exposure or Supplemented Vitamin D Intake Reduce the Severity of COVID-19 Symptoms?

The foremost mortality-causing symptom associated with COVID-19 is acute respiratory distress syndrome (ARDS). A significant correlation has been identified between the deficiency in vitamin D and the risk of developing ARDS. It has been suggested that if we can reduce or modify ARDS in COVID-19 patients, we may significantly reduce the severity of COVID-19 symptoms and associated mortality rates. The increased mortality of dark-skinned people, who have a reduced UV absorption capacity, may be consistent with diminished vitamin D status. The factors associated with COVID-19 mortality, such as old age, ethnicity, obesity, hypertension, cardiovascular diseases, and diabetes, are all found to be linked with vitamin D deficiency. Based on this review and as a precautionary measure, it is suggested that the adoption of appropriate and safe solar exposure and vitamin D enriched foods and supplements should be considered to reduce the possible severity of COVID-19 symptoms. Safe sun exposure is deemed beneficial globally, specifically in low and middle-income countries, as there is no cost involved. It is also noted that improved solar exposure and vitamin D levels can reduce the impact of other diseases as well, thus assisting in maintaining general human well-being.

Association Between Vitamin D and Novel SARS-CoV-2 Respiratory Dysfunction - A Scoping Review of Current Evidence and Its Implication for COVID-19 Pandemic

OBJECTIVES

To assess the association between vitamin D deficiency and increased morbidity/mortality with COVID-19 respiratory dysfunction.

DESIGN

Scoping review.

DATA SOURCES

Ovid MEDLINE (1946 to 24 of April 2020) and PubMed (2020 to 17 of September 2020).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

A search using the search terms: [(cholecalciferol or ergocalciferol or vitamin D2 or vitamin D3 or vitamin D or 25OHD) and (SARS-CoV-2 or coronavirus or COVID or betacoronavirus or MERS-CoV or SARS-CoV or respiratory infection or acute respiratory distress syndrome or ARDS)]m.p. was conducted on the 24/04/2020 (Search A) and 17/09/2020 (Search B).

RESULTS

91 studies were identified as being concerned with Acute Respiratory Infection (ARI)/Acute Respiratory Distress Syndrome (ARDS) and vitamin D, and 25 publications specifically explored the role of vitamin D deficiency in the development and progression of SARS-CoV-2/COVID-19 related ARDS. Search "A" identified three main themes of indirect evidence supporting such an association. Consistent epidemiological evidence exists linking low vitamin D levels to increased risk and severity of respiratory tract infections. We also report on plausible biological processes supporting such an association; and present weaker evidence supporting the benefit of vitamin D supplementation in reducing the risk and severity of ARIs. Uncertainty remains about what constitutes an appropriate dosing regimen in relation to reducing risk/severity of ARI/ARDS. More recent evidence (Search B) provided new insights into some direct links between vitamin D and COVID-19; with a number of cohort and ecological studies supporting an association with PCR-positivity for SARS-CoV-2 and vitamin D deficiency. The exact efficacy of the vitamin D supplementation for prevention of, or as an adjunct treatment for COVID-19 remains to be determined; but a number of randomized control trials (RCTs) currently underway are actively investigating these potential benefits.

CONCLUSION

Our rapid review of literature supports the need for observational studies with COVID-19 infected populations to measure and assess vitamin D levels in relation to risk/severity and outcomes; alongside RCTs designed to evaluate the efficacy of supplementation both in preventive and therapeutic contexts. The overlap in the vitamin D associated biological pathways with the dysregulation reported to drive COVID-19 outcomes warrants further investigation.

Are Adequate Vitamin D Levels Helpful in Fighting COVID-19? A Look at the Evidence

COVID-19 is a global pandemic with high mortality in vulnerable groups. Given the current lack of definitive treatment or vaccine that significantly reduces mortality rate, governments, researchers and healthcare providers are racing to find possible solutions to the crisis. Vitamin D and its analogues have been previously studied for their non-skeletal benefits. In particular, questions regarding their role in the modulation of immunity have re-surfaced, in view of possible epidemiological links observed between COVID-19 and vitamin D levels in selected populations. In this review, we highlight potential mechanisms and summarise the evidence for and against the potential role of vitamin D supplementation in our fight against COVID-19.

Metabolic and Endocrine Challenges

This review aims to provide an overview of metabolic and endocrine challenges in the setting of intensive care medicine. These are a group of heterogeneous clinical conditions with a high degree of overlap, as well as nonspecific signs and symptoms. Several diseases involve multiple organ systems, potentially causing catastrophic dysfunction and death. In the majority of cases, endocrine challenges accompany other organ failures or manifest as a complication of prolonged intensive care unit stay and malnutrition. However, when endocrine disorders present as an isolated syndrome, they are a rare and extreme manifestation. As they are uncommon, these can typically challenge both with diagnosis and management. Acute exacerbations may be elicited by triggers such as infections, trauma, surgery, and hemorrhage. In this complex scenario, early diagnosis and prompt treatment require knowledge of the specific endocrine syndrome. Here, we review diabetic coma, hyponatremia, hypercalcemia, thyroid emergencies, pituitary insufficiency, adrenal crisis, and vitamin D deficiency, highlighting diagnostic tools and tricks, and management pathways through defining common clinical presentations.

Vitamin D receptor stimulation to reduce acute respiratory distress syndrome (ARDS) in patients with coronavirus SARS-CoV-2 infections: Revised Ms SBMB 2020_166

Coronavirus infection is a serious health problem awaiting an effective vaccine and/or antiviral treatment. The major complication of coronavirus disease 2019 (COVID-19), the Acute Respiratory Distress syndrome (ARDS), is due to a variety of mechanisms including cytokine storm, dysregulation of the renin-angiotensin system, neutrophil activation and increased (micro)coagulation. Based on many preclinical studies and observational data in humans, ARDS may be aggravated by vitamin D deficiency and tapered down by activation of the vitamin D receptor. Several randomized clinical trials using either oral vitamin D or oral Calcifediol (25OHD) are ongoing. Based on a pilot study, oral calcifediol may be the most promising approach. These studies are expected to provide guidelines within a few months.

Could Vitamins Help in the Fight Against COVID-19?

There are limited proven therapeutic options for the prevention and treatment of COVID-19. The role of vitamin and mineral supplementation or "immunonutrition" has previously been explored in a number of clinical trials in intensive care settings, and there are several hypotheses to support their routine use. The aim of this narrative review was to investigate whether vitamin supplementation is beneficial in COVID-19. A systematic search strategy with a narrative literature summary was designed, using the Medline, EMBASE, Cochrane Trials Register, WHO International Clinical Trial Registry, and Nexis media databases. The immune-mediating, antioxidant and antimicrobial roles of vitamins A to E were explored and their potential role in the fight against COVID-19 was evaluated. The major topics extracted for narrative synthesis were physiological and immunological roles of each vitamin, their role in respiratory infections, acute respiratory distress syndrome (ARDS), and COVID-19. Vitamins A to E highlighted potentially beneficial roles in the fight against COVID-19 via antioxidant effects, immunomodulation, enhancing natural barriers, and local paracrine signaling. Level 1 and 2 evidence supports the use of thiamine, vitamin C, and vitamin D in COVID-like respiratory diseases, ARDS, and sepsis. Although there are currently no published clinical trials due to the novelty of SARS-CoV-2 infection, there is pathophysiologic rationale for exploring the use of vitamins in this global pandemic, supported by early anecdotal reports from international groups. The final outcomes of ongoing trials of vitamin supplementation are awaited with interest.

Pathways in the Pathophysiology of Coronavirus 19 Lung Disease Accessible to Prevention and Treatment

Background: In COVID 19 related lung disease, which is a leading cause of death from this disease, cytokines like tumor necrosis factor-alpha (TNF alpha) may be pivotal in the pathogenesis. TNF alpha reduces fluid absorption due to impairment of sodium and chloride transport required for building an osmotic gradient across epithelial cells, which in the airways maintains airway surface liquid helping to keep airways open and enabling bacterial clearance and aids water absorption from the alveolar spaces. TNF alpha can, through Rho-kinase, disintegrate the endothelial and epithelial cytoskeleton, and thus break up intercellular tight junctional proteins, breaching the intercellular barrier, which prevents flooding of the interstitial and alveolar spaces with fluid. Hypotheses: (1) Preservation and restoration of airway and alveolar epithelial sodium and chloride transport and the cytoskeleton dependent integrity of the cell barriers within the lung can prevent and treat COVID 19 lung disease. (2) TNF alpha is the key mediator of pulmonary edema in COVID 19 lung disease. Confirmation of hypothesis and implications: The role of a reduction in the function of epithelial sodium and chloride transport could with regards to chloride transport be tested by analysis of chloride levels in exhaled breath condensate and levels correlated with TNF alpha concentrations. Reduced levels would indicate a reduction of the function of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel and a correlation with TNF alpha levels indicative of its involvement. Anti-TNF alpha treatment with antibodies is already available and needs to be tested in randomized controlled trials of COVID 19 lung disease. TNF alpha levels could also be reduced by statins, aspirin, and curcumin. Chloride transport could be facilitated by CFTR activators, including curcumin and phosphodiesterase-5 inhibitors. Sodium and chloride transport could be further regulated to prevent accumulation of alveolar fluid by use of Na(+)/K(+)/2Cl(-) cotransporter type 1 inhibitors, which have been associated with improved outcome in adults ventilated for acute respiratory distress syndrome (ARDS) in randomized controlled trials. Primary prevention of coronavirus infection and TNF alpha release in response to it could be improved by induction of antimicrobial peptides LL-37 and human beta defensin-2 and reduction of TNF alpha production by vitamin D prophylaxis for the population as a whole.

Early Nutritional Interventions with Zinc, Selenium and Vitamin D for Raising Anti-Viral Resistance Against Progressive COVID-19

OBJECTIVES

The novel coronavirus infection (COVID-19) conveys a serious threat globally to health and economy because of a lack of vaccines and specific treatments. A common factor for conditions that predispose for serious progress is a low-grade inflammation, e.g., as seen in metabolic syndrome, diabetes, and heart failure, to which micronutrient deficiencies may contribute. The aim of the present article was to explore the usefulness of early micronutrient intervention, with focus on zinc, selenium, and vitamin D, to relieve escalation of COVID-19.

METHODS

We conducted an online search for articles published in the period 2010-2020 on zinc, selenium, and vitamin D, and corona and related virus infections.

RESULTS

There were a few studies providing direct evidence on associations between zinc, selenium, and vitamin D, and COVID-19. Adequate supply of zinc, selenium, and vitamin D is essential for resistance to other viral infections, immune function, and reduced inflammation. Hence, it is suggested that nutrition intervention securing an adequate status might protect against the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome - coronavirus-2) and mitigate the course of COVID-19.

CONCLUSION

We recommended initiation of adequate supplementation in high-risk areas and/or soon after the time of suspected infection with SARS-CoV-2. Subjects in high-risk groups should have high priority as regards this nutritive adjuvant therapy, which should be started prior to administration of specific and supportive medical measures.

Novel coronavirus infection SARS-CoV-2 in elderly and senile patients: prevention, diagnosis and treatment. Expert Position Paper of the Russian Association of Gerontology and Geriatrics

A novel coronavirus infection SARS-CoV-2 (COVID19) is especially dangerous for elderly and senile patients. Preventive measures for elderly people should cover three areas: 1) direct prevention of the viral infection, 2) preservation of the functional status and prevention of geriatric syndromes, including the use of social support measures, 3) control of comorbidities. The clinical pattern of COVID-19 in older patients may be atypical, while the mildness of symptoms (no fever, cough, shortness of breath) may not correspond to the severity of the prognosis. Delirium may be the first manifestation of COVID-19, which requires special care in its screening. Management of elderly and senile patients with COVID19 should include measures for delirium prevention, the detection and improvement of nutrition. The risk of malnutrition with sarcopenia increases with hospitalization of a patient, especially when using artificial ventilation, is associated with an unfavorable prognosis during hospitalization, accelerates the progression of senile asthenia and reduces the quality of life. Geriatric assessment is the cornerstone of determining the management of an elderly patient.

Vitamin D attenuates lung injury via stimulating epithelial repair, reducing epithelial cell apoptosis and inhibits TGF-β induced epithelial to mesenchymal transition

Vitamin D regulates cell proliferation, inhibits cytokines release at sites of inflammation and reduces inflammatory responses. In this study, the aim was to investigate whether exogenous vitamin D attenuates LPS-induced lung injury via modulating epithelial cell proliferation, migration, apoptosis and epithelial mesenchymal transition (EMT). Murine and in vitro primary type II alveolar epithelial cell work were included in this study. In vivo, mice were mildly vitamin D deficient, 0.1, 1.5, 10 mg/kg 1,25(OH)₂-vitamin D₃ or 25(OH)-vitamin D₃ was administrated by means of an intra-gastric injection for 14 days pre-intra-tracheal (IT) LPS, which remarkedly promoted alveolar epithelial type II cells proliferation, inhibited ATII cells apoptosis and inhibited EMT, with the outcome of attenuated LPS-induced lung injury. In vitro, vitamin D stimulated epithelial cell scratch wound repair, reduced primary ATII cells apoptosis as well. Vitamin D promoted primary human ATII cells proliferation through the PI3K/AKT signaling pathway and activation of vitamin D receptor (VDR). Moreover, vitamin D inhibited EMT in response to TGF-β, which was vitamin D receptor dependent. In conclusion, vitamin D attenuates lung injury via stimulating ATII cells proliferation and migration, reducing epithelial cell apoptosis and inhibits TGF-β induced EMT. Together, these results suggest that vitamin D has therapeutic potential for the resolution of ARDS.

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.

The effect of supplementation of vitamin D in neurocritical care patients: RandomizEd Clinical TrIal oF hYpovitaminosis D (RECTIFY)

OBJECTIVE

Hypovitaminosis D is prevalent in neurocritical care patients, but the potential to improve patient outcome by replenishing vitamin D has not been investigated. This single-center, double-blinded, placebo-controlled, randomized (1:1) clinical trial was designed to assess the effect on patient outcome of vitamin D supplementation in neurocritical care patients with hypovitaminosis D.

METHODS

From October 2016 until April 2018, emergently admitted neurocritical care patients with vitamin D deficiency (≤ 20 ng/ml) were randomized to receive vitamin D3 (cholecalciferol, 540,000 IU) (n = 134) or placebo (n = 133). Hospital length of stay (LOS) was the primary outcome; secondary outcomes included intensive care unit (ICU) LOS, repeat vitamin D levels, patient complications, and patient disposition. Exploratory analysis evaluated specific subgroups of patients by LOS, Glasgow Coma Scale (GCS) score, and Simplified Acute Physiology Score (SAPS II).

RESULTS

Two-hundred seventy-four patients were randomized (intent-to-treat) and 267 were administered treatment within 48 hours of admission (as-treated; 61.2% of planned recruitment) and monitored. The mean age of as-treated patients was 54.0 ± 17.2 years (56.9% male, 77.2% white). After interim analysis suggested a low conditional power for outcome difference (predictive power 0.12), the trial was halted. For as-treated patients, no significant difference in hospital LOS (10.4 ± 14.5 days vs 9.1 ± 7.9 days, p = 0.4; mean difference 1.3, 95% CI -1.5 to 4.1) or ICU LOS (5.8 ± 7.5 days vs 5.4 ± 6.4 days, p = 0.4; mean difference 0.4, 95% CI -1.3 to 2.1) was seen between vitamin D3 and placebo groups, respectively. Vitamin D3 supplementation significantly improved repeat serum levels compared with placebo (20.8 ± 9.3 ng/ml vs 12.8 ± 4.8 ng/ml, p < 0.001) without adverse side effects. No subgroups were identified by exclusion of LOS outliers or segregation by GCS score, SAPS II, or severe vitamin D deficiency (≤ 10 ng/ml).

CONCLUSIONS

Despite studies showing that vitamin D can predict prognosis, supplementation in vitamin D-deficient neurocritical care patients did not result in appreciable improvement in outcomes and likely does not play a role in acute clinical recovery.Clinical trial registration no.: NCT02881957 (clinicaltrials.gov).

Trying to identify who may benefit most from future vitamin D intervention trials: a post hoc analysis from the VITDAL-ICU study excluding the early deaths

Background

Vitamin D supplementation has shown promise for reducing mortality in the intensive care setting. As a steroid prohormone with pleiotropic effects, there may be a lag between administration and observing clinical benefit. This secondary analysis of the VITdAL-ICU study sought to explore whether the effect size of vitamin D on mortality was different when study participants who died or were discharged early were excluded.

Methods

The VITdAL-ICU study was a randomized, placebo-controlled trial in critically ill adults who received placebo or 540,000 IU cholecalciferol followed by monthly supplementation. The effect of vitamin D on 28-day mortality was evaluated after exclusion of participants who died or were discharged within 7 days from study drug administration, according to vitamin D concentrations on day 3, using a bivariate analysis adjusted for confounders and in a stepwise multiple analysis.

Results

Of 475 study participants, 65 died or were discharged within the first 7 days. In the remaining 410 patients, vitamin D supplementation was associated with a reduction in 28-day mortality [OR 0.58 (95% CI 0.35–0.97) p value = 0.035]. The effect on mortality was not significant after adjusting for age, severity scores, female gender, chronic liver and kidney disease, COPD, diagnosis of the tumor, mechanical ventilation, and vasopressors at enrollment (all p > 0.05). In a multiple model, the mortality reduction by vitamin D supplementation did not remain independently significant [OR 0.61 (95% CI 0.35–1.05) p = 0.075].

Vitamin D metabolite response, in the treatment group, demonstrated that survivors at 28 days, had higher levels of 25-hydroxyvitamin D (34.4 vs 25.4 ng/ml, p = 0.010) and 1,25-dihydroxyvitamin D (107.6 vs 70.3 pg/ml, p = 0.049) on day 3. The increase of plasma metabolites after vitamin D oral supplementation, independent of the baseline value, was associated with lower odds of death [OR 0.48 (95% CI 0.27–0.87) p value = 0.016].

Conclusions

High-dose vitamin D3 supplementation was associated with a reduction of 28-day mortality in a mixed population of critically ill adults with vitamin D deficiency when excluding patients who died or were discharged within 7 days after study inclusion. However, this survival benefit was not independently confirmed when adjusted for other factors strongly associated with mortality.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2472-z) contains supplementary material, which is available to authorized users.

Protein Intake, Nutritional Status and Outcomes in ICU Survivors: A Single Center Cohort Study

Background: We hypothesized that protein delivery during hospitalization in patients who survived critical care would be associated with outcomes following hospital discharge. Methods: We studied 801 patients, age ≥ 18 years, who received critical care between 2004 and 2012 and survived hospitalization. All patients underwent a registered dietitian formal assessment within 48 h of ICU admission. The exposure of interest, grams of protein per kilogram body weight delivered per day, was determined from all oral, enteral and parenteral sources for up to 28 days. Adjusted odds ratios for all cause 90-day post-discharge mortality were estimated by mixed- effects logistic regression models. Results: The 90-day post-discharge mortality was 13.9%. The mean nutrition delivery days recorded was 15. In a mixed-effect logistic regression model adjusted for age, gender, race, Deyo-Charlson comorbidity index, acute organ failures, sepsis and percent energy needs met, the 90-day post-discharge mortality rate was 17% (95% CI: 6–26) lower for each 1 g/kg increase in daily protein delivery (OR = 0.83 (95% CI 0.74–0.94; p = 0.002)). Conclusions: Adult medical ICU patients with improvements in daily protein intake during hospitalization who survive hospitalization have decreased odds of mortality in the 3 months following hospital discharge.

Effect of High-Dose Vitamin D on Duration of Mechanical Ventilation in ICU Patients

The relationship of vitamin D3 with the duration of mechanical ventilation and mortality is still unknown. Therefore, this study aimed to determine the effect of using high-dose vitamin D on the duration of mechanical ventilation among the patients admitted to the intensive care unit. The current double-blinded clinical trial was performed on 44 mechanically ventilated, adult patients. Using permuted block randomization, the patients were recruited in intervention and placebo arms. In the placebo group, four patients were excluded due to death before 72 h. The vitamin D level was measured in both groups on entrance and 7^th day of the study. The intervention and placebo groups received intramuscular injection of 300000 IU vitamin D and identical placebo, respectively. SOFA and CPIS score were evaluated daily for 7 days and on 14^th and 28^th days of the study. Also duration of mechanical ventilation and mortality rate were recorded. Fourteen males and 8 females were recruited in the intervention group, as well as 13 males and 5 females in the control group. There was no significant difference in baseline characteristics of the patients including gender and age. The mean duration of the mechanical ventilation was 17.63 ± 14 days in the intervention group versus 27.72 ± 22.48 days in the control group (p = 0.06). Mortality rate in control and intervention groups was 61.1% versus 36.3% (p = 0.00), respectively. Administration of high-dose vitamin D could reduce mortality in mechanically ventilated patients. Despite decrease of 10 days in duration of mechanical ventilation, the difference was not statistically significant. Larger studies are recommended.

Vitamin D to Prevent Lung Injury Following Esophagectomy-A Randomized, Placebo-Controlled Trial

OBJECTIVES

Observational studies suggest an association between vitamin D deficiency and adverse outcomes of critical illness and identify it as a potential risk factor for the development of lung injury. To determine whether preoperative administration of oral high-dose cholecalciferol ameliorates early acute lung injury postoperatively in adults undergoing elective esophagectomy.

DESIGN

A double-blind, randomized, placebo-controlled trial.

SETTING

Three large U.K. university hospitals.

PATIENTS

Seventy-nine adult patients undergoing elective esophagectomy were randomized.

INTERVENTIONS

A single oral preoperative (3-14 d) dose of 7.5 mg (300,000 IU; 15 mL) cholecalciferol or matched placebo.

MEASUREMENTS AND MAIN RESULTS

Primary outcome was change in extravascular lung water index at the end of esophagectomy. Secondary outcomes included PaO2:FIO2 ratio, development of lung injury, ventilator and organ-failure free days, 28 and 90 day survival, safety of cholecalciferol supplementation, plasma vitamin D status (25(OH)D, 1,25(OH)2D, and vitamin D-binding protein), pulmonary vascular permeability index, and extravascular lung water index day 1 postoperatively. An exploratory study measured biomarkers of alveolar-capillary inflammation and injury. Forty patients were randomized to cholecalciferol and 39 to placebo. There was no significant change in extravascular lung water index at the end of the operation between treatment groups (placebo median 1.0 [interquartile range, 0.4-1.8] vs cholecalciferol median 0.4 mL/kg [interquartile range, 0.4-1.2 mL/kg]; p = 0.059). Median pulmonary vascular permeability index values were significantly lower in the cholecalciferol treatment group (placebo 0.4 [interquartile range, 0-0.7] vs cholecalciferol 0.1 [interquartile range, -0.15 to -0.35]; p = 0.027). Cholecalciferol treatment effectively increased 25(OH)D concentrations, but surgery resulted in a decrease in 25(OH)D concentrations at day 3 in both arms. There was no difference in clinical outcomes.

CONCLUSIONS

High-dose preoperative treatment with oral cholecalciferol was effective at increasing 25(OH)D concentrations and reduced changes in postoperative pulmonary vascular permeability index, but not extravascular lung water index.

Vitamin D status and its influence on outcomes following major burn injury and critical illness

Vitamin D deficiency is common among the general population. It is also observed in up to 76% of critically ill patients. Despite the high prevalence of hypovitaminosis D in critical illness, vitamin D is often overlooked by medical staff as the clinical implications and consequences of vitamin D deficiency in acute contexts remain to be fully understood. Vitamin D has a broad range of pleotropic effects on various processes and systems including the immune-inflammatory response. 1α,25-dihydroxyvitamin D (1,25(OH)₂D), has been shown to promote a tolerogenic immune response limiting deleterious inflammatory effects, modulation of the innate immune system, and enhancement of anti-microbial peptides. Vitamin D deficiency is frequently observed in critically ill patients and has been related to extrinsic causes (i.e., limited sunlight exposure), magnitude of injury/illness, or the treatment started by medical doctors including fluid resuscitation. Low levels of vitamin D in critically ill patients have been associated with sepsis, organ failure, and mortality. Despite this, there are subpopulations of critical illness, such as burn patients, where the literature regarding vitamin D status and its influence on outcomes remain insufficient. Thermal injury results in damage to both burned and non-burned tissues, as well as induces an exaggerated and persistent immune-inflammatory and hypermetabolic response. In this review, we propose potential mechanisms in which burn injury affects the vitamin D status and summarizes current literature investigating the influence of vitamin D status on outcomes. In addition, we reviewed the literature and trials investigating vitamin D supplementation in critically ill patients and discuss the therapeutic potential of vitamin D supplementation in burn and critically ill patients. We also highlight current limitations of studies that have investigated vitamin D status and supplementation in critical illness. Thermal injury influences vitamin D status. More studies investigating vitamin D depletion in burn patients and its influence on prognosis, via standardized methodology, are required to reach definitive conclusions and influence clinical practice.

Malnutrition, Critical Illness Survivors, and Postdischarge Outcomes: A Cohort Study

BACKGROUND

We hypothesized that preexisting malnutrition in patients who survived critical care would be associated with adverse outcomes following hospital discharge.

METHODS

We performed an observational cohort study in 1 academic medical center in Boston. We studied 23,575 patients, aged ≥18 years, who received critical care between 2004 and 2011 and survived hospitalization.

RESULTS

The exposure of interest was malnutrition determined at intensive care unit (ICU) admission by a registered dietitian using clinical judgment and on data related to unintentional weight loss, inadequate nutrient intake, and wasting of muscle mass and/or subcutaneous fat. The primary outcome was 90-day postdischarge mortality. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by logistic regression models adjusted for age, race, sex, Deyo-Charlson Index, surgical ICU, sepsis, and acute organ failure. In the cohort, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8%, and 21.9% in patients without malnutrition, those at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition, respectively. The odds of 90-day postdischarge mortality in patients at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition fully adjusted were 1.77 (95% confidence interval [CI], 1.23-2.54), 2.51 (95% CI, 1.36-4.62), and 3.72 (95% CI, 2.16-6.39), respectively, relative to patients without malnutrition. Furthermore, the presence of malnutrition is a significant predictor of the odds of unplanned 30-day hospital readmission.

CONCLUSIONS

In patients treated with critical care who survive hospitalization, preexisting malnutrition is a robust predictor of subsequent mortality and unplanned hospital readmission.

Acute Kidney Injury After Craniotomy Is Associated With Increased Mortality: A Cohort Study

BACKGROUND

Acute kidney injury (AKI) is a serious postoperative complication.

OBJECTIVE

To determine whether AKI in patients after craniotomy is associated with heightened 30-day mortality.

METHODS

We performed a 2-center, retrospective cohort study of 1656 craniotomy patients who received critical care between 1998 and 2011. The exposure of interest was AKI defined as meeting RIFLE (Risk, Injury, Failure, Loss of Kidney Function, and End-stage Kidney Disease) class risk, injury, and failure criteria, and the primary outcome was 30-day mortality. Adjusted odds ratios were estimated by multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both AKI and mortality. Additionally, mortality in craniotomy patients with AKI was analyzed with a risk-adjusted Cox proportional hazards regression model and propensity score matching as a sensitivity analysis.

RESULTS

The incidences of RIFLE class risk, injury, and failure were 5.7%, 2.9%, and 1.3%, respectively. The odds of 30-day mortality in patients with RIFLE class risk, injury, or failure fully adjusted were 2.79 (95% confidence interval [CI], 1.76-4.42), 7.65 (95% CI, 4.16-14.07), and 14.41 (95% CI, 5.51-37.64), respectively. Patients with AKI experienced a significantly higher risk of death during follow-up; hazard ratio, 1.82 (95% CI, 1.34-2.46), 3.37 (95% CI, 2.36-4.81), and 5.06 (95% CI, 2.99-8.58), respectively, fully adjusted. In a cohort of propensity score-matched patients, RIFLE class remained a significant predictor of 30-day mortality.

CONCLUSION

Craniotomy patients who suffer postoperative AKI are among a high-risk group for mortality. The severity of AKI after craniotomy is predictive of 30-day mortality.

ABBREVIATIONS

AKI, acute kidney injuryAPACHE II, Acute Physiology and Chronic Health Evaluation IICI, confidence intervalCPT, Current Procedural TerminologyICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical ModificationRIFLE, risk, injury, failure, loss of kidney function, and end-stage kidney diseaseRPDR, Research Patient Data Registry.

Nucleated red blood cells, critical illness survivors and postdischarge outcomes: a cohort study

Background

Little is known about risk factors associated with out-of-hospital outcomes in survivors of critical illness. We hypothesized that the presence of nucleated red blood cells in patients who survived critical care would be associated with adverse outcomes following hospital discharge.

Methods

We performed a two-center observational cohort study of patients treated in medical and surgical intensive care units in Boston, Massachusetts. All data were obtained from the Research Patient Data Registry at Partners HealthCare. We studied 2878 patients, age ≥ 18 years, who received critical care between 2011 and 2015 and survived hospitalization. The exposure of interest was nucleated red blood cells occurring from 2 days prior to 7 days after critical care initiation. The primary outcome was mortality in the 90 days following hospital discharge. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both nucleated red blood cells and outcome. Adjustment included age, race (white versus nonwhite), gender, Deyo–Charlson Index, patient type (medical versus surgical), sepsis and acute organ failure.

Results

In patients who received critical care and survived hospitalization, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8% and 21.9% in patients with 0/μl, 1–100/μl, 101–200/μl and more than 200/μl nucleated red blood cells respectively. Nucleated red blood cells were a robust predictor of postdischarge mortality and remained so following multivariable adjustment. The fully adjusted odds of 90-day postdischarge mortality in patients with 1–100/μl, 101–200/μl and more than 200/μl nucleated red blood cells were 1.77 (95% CI, 1.23–2.54), 2.51 (95% CI, 1.36–4.62) and 3.72 (95% CI, 2.16–6.39) respectively, relative to patients without nucleated red blood cells. Further, the presence of nucleated red blood cells is a significant predictor of the odds of unplanned 30-day hospital readmission.

Conclusion

In critically ill patients who survive hospitalization, the presence of nucleated red blood cells is a robust predictor of postdischarge mortality and unplanned hospital readmission.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1724-z) contains supplementary material, which is available to authorized users.

Vitamin D Deficiency in Human and Murine Sepsis

Supplemental Digital Content is available in the text.

Objectives:

Vitamin D deficiency has been implicated as a pathogenic factor in sepsis and ICU mortality but causality of these associations has not been demonstrated. To determine whether sepsis and severe sepsis are associated with vitamin D deficiency and to determine whether vitamin D deficiency influences the severity of sepsis.

Design, Setting, and Patients:

Sixty-one patients with sepsis and severe sepsis from two large U.K. hospitals and 20 healthy controls were recruited. Murine models of cecal ligation and puncture and intratracheal lipopolysaccharide were undertaken in normal and vitamin D deficient mice to address the issue of causality.

Measurements and Main Results:

Patients with severe sepsis had significantly lower concentrations of 25-hydroxyvitamin D₃ than patients with either mild sepsis or age-matched healthy controls (15.7 vs 49.5 vs 66.5 nmol/L; p = 0.0001). 25-hydroxyvitamin D₃ concentrations were significantly lower in patients who had positive microbiologic culture than those who were culture negative (p = 0.0023) as well as those who died within 30 days of hospital admission (p = 0.025). Vitamin D deficiency in murine sepsis was associated with increased peritoneal (p = 0.037), systemic (p = 0.019), and bronchoalveolar lavage (p = 0.011) quantitative bacterial culture. This was associated with reduced local expression of the cathelicidin-related antimicrobial peptide as well as evidence of defective macrophage phagocytosis (p = 0.029). In the intratracheal lipopolysaccharide model, 1,500 IU of intraperitoneal cholecalciferol treatment 6 hours postinjury reduced alveolar inflammation, cellular damage, and hypoxia.

Conclusions:

Vitamin D deficiency is common in severe sepsis. This appears to contribute to the development of the condition in clinically relevant murine models and approaches to correct vitamin D deficiency in patients with sepsis should be developed.

Vitamin D Status and Supplementation in the Critically Ill

Vitamin D deficiency has recently been recognized as a widespread global disorder. Generally considered a direct extension of malnutrition, even subclinical hypovitaminosis D is now recognized in adequately nourished populations. Compared to the general population, the prevalence of hypovitaminosis D is greater in the critically ill population. In fact, several studies have shown poorer outcomes in critically ill patients discovered to be vitamin D deficient or insufficient. Controversy persists regarding vitamin D measurements, quantity of supplementation, and appropriate target level in various populations. Vitamin D has a vital role in calcium homeostasis and extra-skeletal health, such as immune function. Therefore, vitamin D supplementation may have a role for improving outcomes in critically ill patients. In this review, we will first discuss the metabolism and function of vitamin D under normal physiologic conditions. We will then explore the prevalence and prognostic value of vitamin D deficiency in critical illness. Finally, we will examine recent trials focusing on appropriate dosing, route of administration, and outcomes associated with vitamin D supplementation in the ICU.

Is Low Serum Vitamin D Associated with Early Dental Implant Failure? A Retrospective Evaluation on 1625 Implants Placed in 822 Patients

Aim. To investigate whether there is a correlation between early dental implant failure and low serum levels of vitamin D. Methods. All patients treated with dental implants in a single centre, in the period 2003–2015, were considered for enrollment in this study. The main outcome was early implant failure. The influence of patient-related variables on implant survival was calculated using the Chi-square test. Results. 822 patients treated with 1625 implants were selected for this study; 27 early failures (3.2%) were recorded. There was no link between gender, age, smoking, history of periodontitis, and an increased incidence of early failures. Statistical analysis reported 9 early failures (2.2%) in patients with serum levels of vitamin D > 30 ng/mL, 16 early failures (3.9%) in patients with levels between 10 and 30 ng/mL, and 2 early failures (9.0%) in patients with levels <10 ng/mL. Although there was an increasing trend in the incidence of early implant failures with the worsening of vitamin D deficiency, the difference between these 3 groups was not statistically significant (P = 0.15). Conclusions. This study failed in proving an effective link between low serum levels of vitamin D and an increased risk of early implant failure. Further studies are needed to investigate this topic.

High Dose Vitamin D Administration in Ventilated Intensive Care Unit Patients: A Pilot Double Blind Randomized Controlled Trial

•

First double blind RCT of vitamin D therapy in mechanically ventilated patients.

•

Treatment with placebo, 250,000 IU or 500,000 IU enteral vitamin D3 was well tolerated.

•

Significant increase in plasma 25(OH)D from baseline to day 7.

•

Significant decrease in hospital length of stay for vitamin D3 treated subjects.

•

No change in plasma LL-37 according to treatment group.

Background

There is a high prevalence of vitamin D deficiency in the critically ill patient population. Several intensive care unit studies have demonstrated an association between vitamin D deficiency [25-hydroxyvitamin D (25(OH)D) < 20 ng/mL] and increased hospital length of stay (LOS), readmission rate, sepsis and mortality.

Material and Methods

Pilot, double blind randomized control trial conducted on mechanically ventilated adult ICU patients. Subjects were administered either placebo, 50,000 IU vitamin D₃ or 100,000 IU vitamin D₃ daily for 5 consecutive days enterally (total vitamin D₃ dose = 250,000 IU or 500,000 IU, respectively). The primary outcome was plasma 25(OH)D concentration 7 days after oral administration of study drug. Secondary outcomes were plasma levels of the antimicrobial peptide cathelicidin (LL37), hospital LOS, SOFA score, duration of mechanical ventilation, hospital mortality, mortality at 12 weeks, and hospital acquired infection.

Results

A total of 31 subjects were enrolled with 13 (43%) being vitamin D deficient at entry (25(OH)D levels < 20 ng/mL). The 250,000 IU and 500,000 IU vitamin D₃ regimens each resulted in a significant increase in mean plasma 25(OH)D concentrations from baseline to day 7; values rose to 45.7 ± 19.6 ng/mL and 55.2 ± 14.4 ng/mL, respectively, compared to essentially no change in the placebo group (21 ± 11.2 ng/mL), p < 0.001. There was a significant decrease in hospital length of stay over time in the 250,000 IU and the 500,000 IU vitamin D₃ group, compared to the placebo group (25 ± 14 and 18 ± 11 days compared to 36 ± 19 days, respectively; p = 0.03). There was no statically significant change in plasma LL-37 concentrations or other clinical outcomes by group over time.

Conclusions

In this pilot study, high-dose vitamin D3 safely increased plasma 25(OH)D concentrations into the sufficient range and was associated with decreased hospital length of stay without altering other clinical outcomes.

Nutritional Status and Mortality in the Critically Ill

OBJECTIVES

The association between nutritional status and mortality in critically ill patients is unclear based on the current literature. To clarify this relation, we analyzed the association between nutrition and mortality in a large population of critically ill patients and hypothesized that mortality would be impacted by nutritional status.

DESIGN

Retrospective observational study.

SETTING

Single academic medical center.

PATIENTS

Six thousand five hundred eighteen adults treated in medical and surgical ICUs between 2004 and 2011.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

All cohort patients received a formal, in-person, standardized evaluation by a registered dietitian. The exposure of interest, malnutrition, was categorized as nonspecific malnutrition, protein-energy malnutrition, or well nourished and determined by data related to anthropometric measurements, biochemical indicators, clinical signs of malnutrition, malnutrition risk factors, and metabolic stress. The primary outcome was all-cause 30-day mortality determined by the Social Security Death Master File. Associations between nutrition groups and mortality were estimated by bivariable and multivariable logistic regression models. Adjusted odds ratios were estimated with inclusion of covariate terms thought to plausibly interact with both nutrition status and mortality. We used propensity score matching on baseline characteristics to reduce residual confounding of the nutrition status category assignment. In the cohort, nonspecific malnutrition was present in 56%, protein-energy malnutrition was present in 12%, and 32% were well nourished. The 30-day and 90-day mortality rates for the cohort were 19.1% and 26.6%, respectively. Nutritional status is a significant predictor of 30-day mortality following adjustment for age, gender, race, medical versus surgical patient type, Deyo-Charlson index, acute organ failure, vasopressor use, and sepsis: nonspecific malnutrition 30-day mortality odds ratio, 1.17 (95% CI, 1.01-1.37); protein-energy malnutrition 30-day mortality odds ratio, 2.10 (95% CI, 1.70-2.59), all relative to patients without malnutrition. In the matched cohort, the adjusted odds of 30-day mortality in the group of propensity score-matched patients with protein-energy malnutrition was two-fold greater than that of patients without malnutrition.

CONCLUSION

In a large population of critically ill adults, an association exists between nutrition status and mortality.

Nutrition: A Primary Therapy in Pediatric Acute Respiratory Distress Syndrome

Appropriate nutrition is an essential component of intensive care management of children with acute respiratory distress syndrome (ARDS) and is linked to patient outcomes. One out of every two children in the pediatric intensive care unit (PICU) will develop malnutrition or have worsening of baseline malnutrition and present with specific micronutrient deficiencies. Early and adequate enteral nutrition (EN) is associated with improved 60-day survival after pediatric critical illness, and, yet, despite early EN guidelines, critically ill children receive on average only 55% of goal calories by PICU day 10. Inadequate delivery of EN is due to perceived feeding intolerance, reluctance to enterally feed children with hemodynamic instability, and fluid restriction. Underlying each of these factors is large practice variation between providers and across institutions for initiation, advancement, and maintenance of EN. Strategies to improve early initiation and advancement and to maintain delivery of EN are needed to improve morbidity and mortality from pediatric ARDS. Both, over and underfeeding, prolong duration of mechanical ventilation in children and worsen other organ function such that precise calorie goals are needed. The gut is thought to act as a "motor" of organ dysfunction, and emerging data regarding the role of intestinal barrier functions and the intestinal microbiome on organ dysfunction and outcomes of critical illness present exciting opportunities to improve patient outcomes. Nutrition should be considered a primary rather than supportive therapy for pediatric ARDS. Precise nutritional therapies, which are titrated and targeted to preservation of intestinal barrier function, prevention of intestinal dysbiosis, preservation of lean body mass, and blunting of the systemic inflammatory response, offer great potential for improving outcomes of pediatric ARDS. In this review, we examine the current evidence regarding dose, route, and timing of nutrition, current recommendations for provision of nutrition to children with ARDS, and the current literature for immune-modulating diets for pediatric ARDS. We will examine emerging data regarding the role of the intestinal microbiome in modulating the response to critical illness.