Vitamin D level and risk of community-acquired pneumonia and sepsis

25-hydroxyvitamin D and parathyroid hormone in new onset sepsis: A prospective study in critically ill patients

Hypovitaminosis D is highly prevalent in critically ill patients, and it has been suggested to be a risk factor for infections, sepsis and higher mortality. We sought to investigate whether serum 25-hydroxyvitamin D (25(OH)D) and parathyroid hormone (PTH) in critically ill patients with new onset sepsis are associated with severity and outcome. We prospectively included 50 consecutive critically ill adult cases with new onset sepsis and 50 healthy controls matched for age and sex. PTH and 25(OH)D were determined in serum via electrochemiluminescence immunoassays at inclusion in the study in all cases and controls, and one week after sepsis onset in cases. Patients had reduced 25(OH)D compared to controls at sepsis onset (7.9 ± 3 vs 24.6 ± 6.7 ng/mL, p < 0.001), whilst PTH was similar (median (range): 34.5 (5.7-218.5) vs 44.2 (14.2-98.1) pg/mL, p = 0.35). In patients, 25(OH)D upon enrollment and one week after did not differ significantly (7.9 ± 3 vs 7 ± 4.3 ng/mL, p = 0.19). All patients presented with hypovitaminosis D (25(OH)D < 20 ng/mL), while 40 patients (80 %) had vitamin D deficiency (25(OH)D < 12 ng/mL) at sepsis onset, including all ten (20 %) nonsurvivors, who died within 28 days from sepsis onset. Patients with sepsis (N = 28) and septic shock (N = 22) as well as survivors (N = 40) and nonsurvivors (N = 10) had similar 25(OH)D at enrollment (p > 0.05). 25(OH)D was positively correlated with ionized calcium (r = 0.46, p < 0.001) and negatively with PTH (p < 0.05), while inflammatory biomarkers or the severity scores exhibited no correlation with 25(OH)D. Patients with septic shock and nonsurvivors had lower PTH than patients with sepsis and survivors respectively (42.2 ± 42.9 vs 73.4 ± 61.9 pg/mL, p = 0.04, and 18.3 ± 10.7 vs 69.9 ± 58.8 pg/mL, p = 0.001, respectively). C-reactive protein was negatively associated with PTH (r = -0.44, p = 0.001). In conclusion, vitamin D deficiency was present in 80 % of critically ill patients at sepsis onset, while nonsurvivors exhibited lower PTH than survivors. Additional, larger and multicenter studies are warranted to elucidate the contribution of vitamin D and PTH to the pathogenesis of sepsis and its outcomes.

The Vitamin D Serum Levels in Pregnant Women Affected by COVID-19: A Systematic Review and Meta-Analysis

Vitamin D can modulate immune responses, and its deficiency is linked to increased autoimmunity and susceptibility to infection. In the general population, it has been observed that serum vitamin D levels are connected with the risk of COVID-19 and its severity. Our study aims to examine reported findings on the effect of vitamin D serum levels on infection of COVID-19 during pregnancy. PubMed, Web of Science, Embase, and Cochrane Library were searched for relevant studies. Serum vitamin D serum levels in COVID-19-positive and COVID-19-negative pregnant women were 24.61 ± 20.86 ng/mL and 24.12 ± 17.33 ng/mL, respectively. In mild vs. moderate to critical COVID-19 pregnant women, vitamin D serum levels were 16.71 ± 9.04 ng/mL vs. 10.7 ± 9.37 ng/mL and severe vs. non-severe were 13.21 ± 11.47 ng/mL vs. 15.76 ± 10.0 ng/mL. Only one study reported vitamin D serum levels in the placenta of COVID-19-positive pregnant women compared with the control and results varied and amounted to 14.06 ± 0.51 ng/mL vs. 12.45 ± 0.58 ng/mL, respectively. Vitamin D deficiency tends to be common in pregnant women who have COVID-19, and the level of this vitamin has been demonstrated to have a strong correlation with the severity of the illness. As vitamin D serum levels correlate with COVID-19 symptoms and even with its occurrence, appropriate vitamin D supplementation in the prenatal period is suggested.

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.

Serum Vitamin D Level and Risk of Community-Acquired Pneumonia: A Case-Control Study

Introduction

Recent research has shown conflicting evidence on the connection between vitamin D deficiency and community-acquired pneumonia (CAP) in children. Thus, we hypothesized that vitamin D deficiency could be a risk factor for CAP.

Methods

Hospitalized children between 2 and 60 months with physician-diagnosed, radiologically confirmed severe community-acquired pneumonia (CAP) were enrolled as cases. Age-matched controls were enrolled from immunization and weighing clinics. A blood sample was collected to assess serum 25-(OH)D concentration. Unconditional logistic regression was done to examine the independent association of vitamin D level with community-acquired pneumonia.

Results

Seventy-four children (females: 68%) were included. Overall, 27% had vitamin D deficiency (<20 ng/mL) and 37.8% had insufficiency (20-29 ng/mL). The vitamin D level ranged from 8.67 to 46.2 ng/mL. There was no statistically significant difference in 25(OH)D levels in controls and cases (p=0.694). In unconditional logistic regression, 25(OH)D concentration was not a determinant of CAP (OR: 0.99, CI: 0.937-1.044, p=0.689). This lack of association remained after adjustment for age, gender, income, crowding, and exposure to passive smoke (OR: 0.99, CI: 0.937-1.065, p=0.973). Household income was significantly associated with CAP (OR: 0.11, 95% CI: 0.021-0.567, p=0.008).

Conclusion

Two-thirds of the children with CAP had vitamin D deficiency/insufficiency. In comparison with healthy controls, vitamin D level was not a significant determinant of community-acquired pneumonia. It informs that further multisite research is required using more rigorous scientific methods for conclusive evidence on the relationship between vitamin D and CAP.

Correlation between 25-hydroxy vitamin D levels and COVID-19 severity in pregnant women: a cross-sectional study

OBJECTIVE

To evaluate the relationship between 25-hydroxy vitamin D (25(OH)D) levels and disease severity in hospitalized COVID-19 positive pregnant women.

METHODS

The COVID-19 (+) pregnant women (confirmed by PCR test) were classified as asymptomatic, mild symptomatic, and severe disease according to their symptoms and laboratory results. Severe COVID-19 criteria were respiratory symptoms and/or findings. The following laboratory results were considered as poor prognostic factors: the number of lymphocytes <800/µl and/or CRP value >10 times the upper limit of the normal range and/or ferritin value >500 ng/ml and/or D-Dimer value >1000 µg/l. The patients were divided into two groups; asymptomatic or mild symptomatic group (Group 1), and severe disease and/or poor prognostic factor group (Group 2). The 25(OH)D levels were compared between groups. ROC curve analysis was used to analyze the cutoff value for vitamin D to predict the severity of COVID-19.

RESULTS

25(OH)D levels were found to be statistically significantly lower in group 2 (15.5 (10.25) ng/ml in Group 1, 13 (12) ng/ml in Group 2, p = .010). The 25(OH)D level under 14.5 ng/ml was associated with severe COVID-19 and/or poor prognostic factors (p = .010). The risk of severe COVID-19 and/or having poor prognostic factors was 1.87 times higher among pregnant women who had 25(OH)D levels below 14.5 ng/ml. This value was found to have 54.1% sensitivity and 61.3% specificity in predicting severe COVID-19 and/or poor prognostic laboratory findings in pregnant women.

CONCLUSION

There is a relationship between vitamin D status and the severity of COVID-19 in pregnant women. During the pandemic period, vitamin D supplementation for pregnant women should gain more importance.

Challenges and Opportunities for Osteoporosis Care During the COVID-19 Pandemic

PURPOSE

The coronavirus disease 2019 (COVID-19) has both directly and indirectly affected osteoporosis diagnosis and treatment throughout the world.

METHODS

This mini-review summarizes the available evidence regarding the effects of COVID-19, its treatment, and the consequences of the pandemic itself on bone health. Additionally, we review evidence and expert recommendations regarding putative effects of osteoporosis medications on COVID-19 outcomes and vaccine efficacy and summarize recommendations for continuation of osteoporosis treatment during the pandemic.

RESULTS

The use of standard screening procedures to assess for osteoporosis and fracture risk declined dramatically early in the pandemic, while rates of fragility fractures were largely unchanged. COVID-19, its treatments, and public health measures to prevent viral spread are each likely to negatively affect bone health. Osteoporosis treatments are not known to increase risk of adverse events from COVID-19, and preclinical data suggest possible beneficial effects of some therapies. Vitamin D deficiency is clearly associated with adverse outcomes from COVID-19, but it remains unclear whether vitamin D supplementation may improve outcomes. Osteoporosis treatment should be continued whenever possible, and recommendations for substituting therapies, if required, are available.

CONCLUSION

The COVID-19 pandemic has decreased screening and disrupted treatment for osteoporosis. Osteoporosis medications are safe and effective during the pandemic and should be continued whenever possible. Further studies are needed to fully understand the impact of the COVID-19 pandemic on long-term bone health.

Role of vitamin D, serum zinc, and serum iron deficiency in community-acquired pneumonia in children

Background

Community-acquired pneumonia is a major cause of death among children. Inadequate nutrition disrupts the immune system and increases the susceptibility to infections. We aimed to evaluate the association between vitamin D, serum zinc, and iron, and pneumonia. A case-control study was conducted at the outpatient clinic and emergency room of Children’s Hospital. Thirty-one patients with community-acquired pneumonia and 36 healthy children (control group) underwent serum sampling for vitamin D, zinc, and iron.

Results

Most patients had mild form (n = 17, 54.8%). All patients survived and were discharged. The serum iron level showed a non-significant difference between pneumonia and control groups (p ˃ 0.05). TIBC, vitamin D, and serum zinc were significantly lower in the patient group than the control group (P value = 0.04, < 0.001, and 0.03, respectively). Vitamin D deficiency was highly associated with the severity of pneumonia (P value = 0.008).

Conclusion

Adequate serum zinc and vitamin D levels may be protective against infection with community-acquired pneumonia in children aged from 2 months to 5 years old, but not iron.

Baseline Levels of Vitamin D in a Healthy Population from a Region with High Solar Irradiation

The use of vitamin D (VitD) supplements has become widespread in the last decade due not only to the dissociation between the blood levels recommended as "optimal" and those shown by the healthy population but also to its presumed beneficial effects on multiple disorders. This work evaluated the levels of 25-hydroxyvitamin D (25(OH)D) in a healthy population of European origin living in a region with high solar irradiation. In serum samples from a population-based study conducted in the Canary Islands, levels of 25(OH)D were analyzed. In 876 individuals who had no history of kidney or malabsorption disorders and, who had not been treated with calcium and/or VitD supplementation, the median 25(OH)D level was 26.3 (5th; 95th percentile, 14.3; 45.8) ng/mL. Notably, 65.4% of the population had 25(OH)D blood levels below 30 ng/mL, 23.4% below 20 ng/mL and 6.4% below 15 ng/mL. Based on the lack of evidence supporting causality between 25(OH)D levels below what is recommended as optimal (≥20 ng/mL, or even ≥30 ng/mL) and major skeletal and non-skeletal diseases, and in light of the distribution of the concentration of this vitamin in healthy adults living under optimal conditions of solar irradiation, it seems reasonable to consider 25(OH)D levels below 20 ng/mL and close to 15 ng/mL as adequate for the general population.

Vitamin D and Hospital Admission in Older Adults: A Prospective Association

The health effects of vitamin D are well documented, with increasing evidence of its roles beyond bone. There is, however, little evidence of the effects of vitamin D on hospitalisation among older adults. This study aimed to prospectively determine the relationship of vitamin D status in older adults with hospital admission and emergency department (ED) attendance. Trinity University of Ulster Department of Agriculture (TUDA) is a large cross-sectional study of older adults with a community population from three disease-defined cohorts (cognitive dysfunction, hypertension, and osteoporosis). Participants included in this analysis were recruited between 2008 and 2012. ED and hospital admission data were gathered from the date of TUDA participation until June 2013, with a mean follow up of 3.6 years. Of the 3093 participants, 1577 (50.9%) attended the ED during the period of follow-up. Attendees had lower mean serum 25(OH)D concentrations than non-attendees (59.1 vs. 70.6 nmol/L). Fully adjusted models showed an inverse association between vitamin D and ED attendance (Hazard Ratio (HR) 0.996; 95% Confidence Interval (CI) 0.995-0.998; p < 0.001). A total of 1269 participants (41%) were admitted to hospital during the follow-up. Those admitted had lower mean vitamin D concentrations (58.4 vs. 69.3 nmol/L, p < 0.001). In fully adjusted models, higher vitamin D was inversely associated with hospital admission (HR 0.996; 95% CI 0.994-0.998; p < 0.001) and length of stay (LOS) (β = -0.95, p = 0.006). This study showed independent prospective associations between vitamin D deficiency and increased hospitalisation by older adults. The need for further evaluation of current recommendations in relation to vitamin D supplementation, with consideration beyond bone health, is warranted and should focus on randomised controlled trials.

Low vitamin D and risk of bacterial pneumonias: Mendelian randomisation studies in two population-based cohorts

BACKGROUND

Vitamin D may regulate the innate immune system, and randomised controlled trials suggest a beneficial effect of vitamin D supplementation against acute respiratory tract infections. By using a Mendelian randomisation approach, we tested the hypothesis that low 25-hydroxyvitamin D is associated with increased risk of bacterial pneumonia in observational and genetic analyses.

METHODS

We genotyped 116 335 randomly chosen white Danes aged 20 to 100 from the Copenhagen City Heart Study and Copenhagen General Population Study for plasma 25-hydroxyvitamin D decreasing genetic variants around CYP2R1 (rs117913124, rs12794714 and rs10741657), DHCR7 (rs7944926 and rs11234027), GEMIN2 (rs2277458) and HAL (rs3819817). Information on plasma 25-hydroxyvitamin D was available on 35 833 individuals. Individuals were followed from 1981 through 2018 for hospital diagnoses of bacterial pneumonias.

RESULTS

During up to 38 years follow-up, we observed 6342 bacterial pneumonias in observational analyses and 13 916 in genetic analyses. In observational analyses, multivariable adjusted HR for bacterial pneumonias was 1.27 (95% CI: 1.16 to 1.40) for individuals with 25-hydroxyvitamin D<25 nmol/L compared with those with ≥25 nmol/L. In genetic analyses, the OR for bacterial pneumonia per 10 nmol/L lower plasma 25-hydroxyvitamin D was 1.12 (95% CI: 1.02 to 1.23) in Wald's ratio, 1.12 (95% CI: 1.04 to 1.20) in inverse-variance weighted, 1.63 (95% CI: 0.96 to 2.78) in MR-Egger and 1.15 (95% CI: 1.05 to 1.26) in weighted median instrumental variable analysis. This association was strongest for genetic variants around CYP2R1. There was no observational or genetic evidence to support that 25-hydroxyvitamin D is associated with risk of urinary tract infections, skin infections, sepsis or gastroenteritis, which were used as negative control outcomes.

CONCLUSIONS

Low vitamin D is associated observationally and genetically with increased risk of bacterial pneumonias.

Efficacy of High-Dose Vitamin D Supplementation as an Adjuvant Treatment on Pneumonia: Systematic Review and a Meta-Analysis of Randomized Controlled Studies

The purpose of this meta-analysis was to summarize randomized controlled trial (RCT) evidence and evaluate the efficacy and safety of vitamin D (VD) supplementation as an adjunct to antibiotics for the treatment of pneumonia. Data sources published from the inception dates up to January 2020 were searched. RCTs of VD supplementation of any duration, age, and dosing regimen type were eligible for inclusion if data on pneumonia were collected. Thirteen studies (4786 randomized participants) fulfilled eligibility criteria. VD supplementation significantly increased levels of serum 25(OH)D (mean difference = 15.97; 95% CI, 7.49-24.44; P = .002) and reduced incidence of repeat episodes of pneumonia (risk ratio [RR] = 0.68; 95% CI, 0.50-0.93; P = .02). Subgroup analysis revealed VD supplementation had more reducing effects on repeat episodes of pneumonia among participants in trials in which the population were children (RR = 0.66; 95% CI, 0.48-0.90), duration <3 months (RR = 0.55; 95% CI, 0.33-0.91), or dose of VD <300,000 IU (RR = 0.51; 95% CI, 0.29-0.89). Although our results suggested that VD supplementation had a positive effect on recovery rate of pneumonia (RR = 1.28; 95% CI, 0.94-1.74; I² = 13%), there was no statistical difference (P = .12). High-dose VD intervention may have an effect on reducing the incidence rate of repeat episodes of pneumonia by enhancing immune efficacy, although more population studies are needed to support that VD supplementation has therapeutic effects on pneumonia itself.

Plasma vitamin D, past chest illness, and risk of future chest illness in chronic spinal cord injury (SCI): a longitudinal observational study

STUDY DESIGN

Observational study.

OBJECTIVE

Assess associations between vitamin D levels and other risk factors on future chest illness in a chronic spinal cord injury (SCI) cohort.

SETTING

Veterans Affairs Boston and the Boston, MA community.

METHODS

Between August 2009 and August 2017, 253 participants with chronic SCI were followed over a median of 3.2 years (up to 7.4 years) with two to four visits a median of 1.7 years apart. At each visit, plasma 25-hydroxyvitamin D level was obtained, spirometry performed, and a respiratory questionnaire assessing chest illnesses since last visit was completed. Repeated measures negative binomial regression was used to assess chest illness risk longitudinally.

RESULTS

At entry, 25% had deficient vitamin D levels (<20 nanograms/milliliter (ng/ml)), 52% were insufficient (20 to <30 ng/ml), and 23% were sufficient (≥30 ng/ml). Over 545 study visits, chest illnesses (n = 106) were reported by 60 participants. In multivariable models (including previous chest illness history), deficient vitamin D levels (compared with those with sufficient levels) were associated with future chest illness though with wide confidence limits (relative risk (RR) = 1.36, 95% confidence intervals (CI) = 0.74, 2.47). The strongest association with chest illness during the follow-up period was in persons who reported pneumonia/bronchitis after injury and a chest illness in the three years before study entry (RR = 7.62; 95% CI = 3.70, 15.71).

CONCLUSION

Assessed prospectively in chronic SCI, there was a suggestive association between deficient vitamin D levels and future chest illness. Past chest illness history was also strongly associated with future chest illness.

Reduced Vitamin D Levels are Associated with Stroke-Associated Pneumonia in Patients with Acute Ischemic Stroke

Background and aim

Stroke-associated pneumonia (SAP) is a common complication in patients with acute ischemic stroke (AIS). This study explored the potential relationship between serum vitamin D levels and SAP.

Methods

This study recruited 863 consecutive AIS patients. In-hospital SAP was defined as a complication that occurred after stroke, during hospitalization, that was confirmed radiographically. Serum vitamin D levels were measured within 24 hrs of admission and the patients were divided into vitamin D sufficient (>50 nmol/L), insufficient (25–50 nmol/L), and deficient (<25 nmol/L) groups.

Results

In this study, 102 (11.8%) patients were diagnosed with SAP. Compared to the patients without SAP, patients with SAP had significantly lower vitamin D levels (P = 0.023). The incidence of SAP was significantly higher in patients with vitamin D deficiency than in those with vitamin D insufficiency or sufficiency (21.2% vs 16.2% & 9.5%, P = 0.006). After adjusting for confounders, vitamin D deficiency and insufficiency were independently associated with SAP (OR = 3.034, 95% CI = 1.207–7.625, P = 0.018; OR = 1.921, 95% CI = 1.204–3.066, P = 0.006, respectively). In multiple-adjusted spline regression, vitamin D levels showed a linear association with the risk of SAP (P < 0.001 for linearity).

Conclusion

Reduced vitamin D is a potential risk factor of in-hospital SAP, which can help clinicians identify high-risk SAP patients.

Association between micronutrient deficiency and acute respiratory infections in healthy adults: a systematic review of observational studies

Background

Acute respiratory infections (ARI), including the common cold causes significant morbidity and economical losses globally. Micronutrient deficiency may increase ARI incidence risk and its associated duration and severity among healthy adults, but evidence are inconclusive. This study aims to systematically review all observations on the association between single micronutrient deficiency and ARI incidence, duration and severity in healthy adults.

Methods

Systematic literature searches were conducted in PubMed, Cochrane Library, Embase and Scopus databases. Eligible studies were assessed for the reporting and methodological quality. Adjusted summary statistics with their relevant 95% confidence intervals or interquartile ranges were extracted for the outcomes of interest.

Results

The literature search identified 423 unique studies. Of which, only eight studies were eligible and included in the final review. Only vitamin D deficiency (VDD) was observed among these eight studies. There were no eligible studies that focused on the association between other single micronutrient deficiency and ARI. The review found mixed observations on ARI incidence, and a lack of evidence on its associated severity to conclude the association between VDD and these outcomes. However, existing evidence consistently suggested that VDD is likely to lead to longer ARI duration (median duration in days: deficient group, 4 to 13; non-deficient groups, 2 to 8).

Conclusion

This review found that VDD may be associated to longer ARI duration, but its effect on ARI incidence and its associated severity among healthy adults remains inconclusive. This review also highlighted the lack of a consistent regional and/or global definition for micronutrient sufficiency, and that future studies should explore and conclude the association between other micronutrient deficiency and ARIs in healthy adults before considering supplementation for ARI prevention and management.

The association between vitamin D deficiency and community-acquired pneumonia: A meta-analysis of observational studies

Emerging evidence has shown that vitamin D deficiency may be related with community-acquired pneumonia (CAP), but individually published studies showed inconclusive results. The aim of this study was to quantitatively summarize the association between vitamin D and the CAP.We conducted this meta-analysis though a systematic literature search of PubMed, Medline, and EMBASE up to 31 September 2018 with the following keywords 'vitamin D' or 'cholecalciferol' or '25-hydroxyvitamin D' or '25(OH)D' in combination with 'community-acquired pneumonia' or 'CAP' or 'pneumonia' with no limitations. This meta-analysis was performed following the guidelines of Meta-analysis of Observational Studies in Epidemiology. The association between vitamin D levels and CAP were measured as odds ratio (OR) and weighted mean difference (WMD). Results were combined using a random-effect or a fix-effect meta-analysis, and sensitivity analyses were conducted to explore potential factors.Eight observational studies involving 20,966 subjects were included. In this meta-analysis, CAP patients with vitamin D deficiency (serum 25(OH)D levels <20 ng/mL) experienced a significantly increased risk of CAP (odds ratio (OR) = 1.64, 95% confidence intervals (CI): 1.00, 2.67), and an obvious decrease of -5.63 ng/mL (95% CI: -9.11, -2.14) in serum vitamin D was demonstrated in CAP patients. Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect.The evidence from this meta-analysis indicates an association between vitamin D deficiency and an increased risk of CAP patients. However, well-designed trails are required to determine the explicit effect of vitamin D supplementation.

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.

Vitamin D Deficiency is Associated with Increased Use of Antimicrobials among Preschool Girls in Ethiopia

Preschool children in Addis Ababa, Ethiopia, are highly exposed to influenza viruses. Factors related to infections, nutrition, and environmental conditions that might explain the burden of influenza among these children were investigated. Ninety-five preschool children, 48 girls and 47 boys, were followed clinically for 12 months. Illness and immune responses to influenza; three other respiratory viruses; five airway pathogenic bacteria; and levels of vitamins D, A, and B12 were assessed. Most of the children had antibodies to numerous respiratory viral and bacterial agents at study start, and many were infected during follow-up. Twenty-five girls and 25 boys fell ill during the study, and were treated with one or more courses of systemic antimicrobials. Ninety percent of both girls and boys had 25-hydroxyvitamin D [25(OH)D] levels below the recommended levels. While there was no overall difference in the levels of vitamins D, A, and B12 between girls and boys, treated girls had significantly lower 25(OH)D levels than non-treated girls and treated boys. There was a considerable number of short for age children, but only the short treated girls had significantly lower 25(OH)D levels than the non-treated children. Preschool girls with low 25(OH)D levels were more vulnerable to pathogenic microbes than boys.

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.

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.

Association between serum 25-hydroxyvitamin D concentration and pulmonary infection in children

We assessed the relationship between serum 25-hydroxyvitamin D (25(OH)D) level and community-acquired pneumonia (CAP) among Chinese children.This observational study examined children aged 3 days to 14 years (n = 1582) from the Capital Institute of Pediatrics in 2009 to 2011. There were 797 children in the CAP group and 785 controls. The CAP group was divided into 2 groups: a pneumonia group and pneumonia-induced sepsis group. The serum 25(OH)D level was estimated using micro whole blood chemiluminescence.The average serum 25(OH)D level in all samples was 25.32 ± 14.07 ng/mL, with the CAP group showing a lower value than the control group (P < .001). There were also significant differences between the pneumonia group and pneumonia-induced sepsis group (P < .001). In the pneumonia-induced sepsis group, significant differences in serum 25(OH)D levels were observed in children who received mechanical ventilation or presenting with multiple organ dysfunction (P < .01).All serum 25(OH)D levels in the pneumonia group and pneumonia-induced sepsis group were below normal levels, particularly in the sepsis group. A lower serum 25(OH)D level was associated with more serious symptoms in CAP children. Children with low serum 25(OH)D levels may be at higher risk of receiving mechanical ventilation and presenting with multiple organ dysfunction. These findings suggest that vitamin D supplements are beneficial for the treatment and prevention of CAP.

1,25-Dihydroxyvitamin D Inhibits LPS-Induced High-Mobility Group Box 1 (HMGB1) Secretion via Targeting the NF-E2-Related Factor 2-Hemeoxygenase-1-HMGB1 Pathway in Macrophages

1,25-Dihydroxyvitamin D [1,25(OH)₂D₃] is recognized as a key mediator of inflammatory diseases, including sepsis. Clinical studies demonstrate that 1,25 (OH)₂D₃ protects patients from sepsis, but clinical treatment with 1,25(OH)₂D₃ is rare. In this study, we report that 1,25(OH)₂D₃ treatment has beneficial effects and improves the survival rate in LPS-induced mouse sepsis model by blocking the secretion of high-mobility group box 1 (HMGB1), a key late regulator of sepsis. LPS-induced HMGB1 secretion is attenuated by 1,25(OH)₂D₃via blocking HMGB1 translocation from the nucleus to the cytoplasm in macrophages. 1,25(OH)₂D₃ can induce the expression of hemeoxygenase-1 (HO-1), which is essential for blocking HMBG1 nuclear translocation and its secretion. When siHO-1 or an HO-1 inhibitor are used, the effect of 1,25(OH)₂D₃ on inhibition of HMGB1 secretion is suppressed. Considering that HO-1 is a downstream gene of NF-E2-related factor 2 (Nrf2), we further confirm that Nrf2 activation can be activated by 1,25(OH)₂D₃ upon LPS exposure. Together, we provide evidence that 1,25(OH)₂D₃ attenuates LPS-induced HMGB1 secretion via the Nrf2/HO-1 pathway in macrophages.

25(OH)D and 1,25(OH)D vitamin D fails to predict sepsis and mortality in a prospective cohort study

The clinical role of vitamin D in sepsis and mortality prediction is controversially discussed. Therefore, we conducted a prospective cohort study on standard care wards, including 461 patients with suspected sepsis fulfilling two or more SIRS criteria. On the first and third day after onset of SIRS symptoms levels of 25(OH)D, 1,25(OH)D and sepsis biomarkers were analysed for their predictive capacity for identifying infection, bacteraemia and an elevated mortality risk. Additionally, several SNPs associated with vitamin D metabolism were evaluated. Bacteraemic patients (28.5%) presented with significantly lower 1,25(OH)D levels than SIRS patients without bacteraemia on the first and third day, while 25(OH)D did not show a predictive capacity. No significant differences of either 1,25(OH)D or 25(OH)D levels were found between SIRS patients with and without infections or between survivors and non-survivors. Sepsis biomarkers, including procalcitonin and CRP, showed a significantly higher discriminatory capacity for these classification tasks. The vitamin D metabolism-related SNPs analysed did not indicate any association with our outcome measures. In conclusion, 1,25(OH)D but not 25(OH)D showed a minor discriminatory value for the prediction of bacteraemia that was inferior to CRP and PCT but both failed to predict sepsis and mortality in a prospective cohort of SIRS patients.

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.

Maternal Vitamin D Level Is Associated with Viral Toll-Like Receptor Triggered IL-10 Response but Not the Risk of Infectious Diseases in Infancy

Reports on the effect of prenatal vitamin D status on fetal immune development and infectious diseases in childhood are limited. The aim of this study was to investigate the role of maternal and cord blood vitamin D level in TLR-related innate immunity and its effect on infectious outcome. Maternal and cord blood 25 (OH)D level were examined from 372 maternal-neonatal pairs and their correlation with TLR-triggered TNF-α, IL-6, and IL-10 response at birth was assessed. Clinical outcomes related to infection at 12 months of age were also evaluated. The result showed that 75% of the pregnant mothers and 75.8% of the neonates were vitamin deficient. There was a high correlation between maternal and cord 25(OH)D levels (r = 0.67, p < 0.001). Maternal vitamin D level was inversely correlated with IL-10 response to TLR3 (p = 0.004) and TLR7-8 stimulation (p = 0.006). However, none of the TLR-triggered cytokine productions were associated with cord 25(OH)D concentration. There was no relationship between maternal and cord blood vitamin D status with infectious diseases during infancy. In conclusion, our study had shown that maternal vitamin D, but not cord vitamin D level, was associated with viral TLR-triggered IL-10 response.

Community-onset sepsis and its public health burden: a systematic review

BACKGROUND

Sepsis is a life-threatening condition and major contributor to public health and economic burden in the industrialised world. The difficulties in accurate diagnosis lead to great variability in estimates of sepsis incidence. There has been even greater uncertainty regarding the incidence of and risk factors for community-onset sepsis (COS). We systematically reviewed the recent evidence on the incidence and risk factors of COS in high income countries (North America, Australasia, and North/Western Europe).

METHODS

Cohort and case-control studies were eligible for inclusion. Medline and Embase databases were searched from 2002 onwards. References of relevant publications were hand-searched. Two reviewers screened titles/abstracts and full-texts independently. One reviewer extracted data and appraised studies which were cross-checked by independent reviewers. Disagreements were resolved via consensus. Odds ratios (ORs) and 95 percent confidence intervals (95 % CIs) were ascertained by type of sepsis (non-severe, severe, and septic shock).

RESULTS

Ten cohort and 4 case-control studies were included. There was a wide variation in the incidence (# cases per 100,000 per year) of non-severe sepsis (range: 64-514), severe sepsis (range: 40-455), and septic shock (range: 9-31). Heterogeneity precluded statistical pooling. Two cohort and 4 case-control studies reported risk factors for sepsis. In one case-control and one cohort study, older age and diabetes were associated with increased risk of sepsis. The same case-control study showed an excess risk for sepsis in participants with clinical conditions (e.g., immunosuppression, lung disease, and peripheral artery disease). In one cohort study, higher risk of sepsis was associated with being a nursing home resident (OR = 2.60, 95 % CI: 1.20, 5.60) and in the other cohort study with being physically inactive (OR = 1.33, 95 % CI: 1.13, 1.56) and smoking tobacco (OR = 1.85, 95 % CI: 1.54, 2.22). The evidence on sex, ethnicity, statin use, and body mass index as risk factors was inconclusive.

CONCLUSIONS

The lack of a valid standard approach for defining sepsis makes it difficult to determine the true incidence of COS. Differences in case ascertainment contribute to the variation in incidence of COS. The evidence on COS is limited in terms of the number and quality of studies. This review highlights the urgent need for an accurate and standard method for identifying sepsis. Future studies need to improve the methodological shortcomings of previous research in terms of case definition, identification, and surveillance practice.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015023484.

Vitamin Status among Breastfed Infants in Bhaktapur, Nepal

Vitamin deficiencies are known to be common among infants residing in low- and middle-income countries but relatively few studies have assessed several biochemical parameters simultaneously. The objective of the study was to describe the status of vitamins (A, D, E, B₆, B₁₂ and folate) in breastfed infants. We measured the plasma concentrations of trans retinol, 25 hydroxy vitamin D, α-tocopherol, pyridoxal 5′-phosphate, cobalamin, folate, methylmalonic acid, homocysteine, hemoglobin and C-reactive protein from 467 randomly selected infants. One in five (22%) was deficient in at least one vitamin. Mean (SD) plasma folate concentration was 73 (35) nmol/L, and no infant in the sample was folate deficient. Vitamin B₆ deficiency and vitamin B₁₂ deficiency was found in 22% and 17% of the infants, respectively. Elevated plasma methylmalonic acid or total homocysteine concentration was found in 82% and 62% of infants, respectively. Fifteen percent of infants were vitamin A deficient and 65% were marginally deficient in vitamin A. Fewer than 5% of infants had low plasma vitamin D concentration or vitamin E concentration (α-tocopherol <9.3 µmol/L). Our results illustrate the importance of continued supplementation campaigns and support the expansion of food fortification and dietary diversification programs that target children and women in Nepal.

Vitamin D deficiency at admission is not associated with 90-day mortality in patients with severe sepsis or septic shock: Observational FINNAKI cohort study

Introduction Low levels of vitamin D have been associated with increased mortality in patients that are critically ill. This study explored whether vitamin D levels were associated with 90-day mortality in severe sepsis or septic shock. Methods Plasma vitamin D levels were measured on admission to the intensive care unit (ICU) in a prospective multicentre observational study. Results 610 patients with severe sepsis were included; of these, 178 (29%) had septic shock. Vitamin D deficiency (<50 nmol/L) was present in 333 (55%) patients. The 90-day mortality did not differ among patients with or without vitamin D deficiency (28.3% vs. 28.5%, p = 0.789). Diabetes was more common among patients deficient compared to those not deficient in vitamin D (30% vs. 18%, p < 0.001). Hospital-acquired infections at admission were more prevalent in patients with a vitamin D deficiency (31% vs. 16%, p < 0.001). A multivariable adjusted Cox regression model showed that low vitamin D levels could not predict 90-day mortality (<50 nmol/L: hazard ratio (HR) 0.99 (95% CI: 0.72-1.36), p > 0.9; and <25 nmol/L: HR 0.44 (95% CI: 0.22-0.87), p = 0.018). Conclusions Vitamin D deficiency detected upon ICU admission was not associated with 90-day mortality in patients with severe sepsis or septic shock. Key messages In severe sepsis and septic shock, a vitamin D deficiency upon ICU admission was not associated with increased mortality. Compared to patients with sufficient vitamin D, patients with deficient vitamin D more frequently exhibited diabetes, elevated C-reactive protein levels, and hospital-acquired infections upon ICU admission, and they more frequently developed acute kidney injury.

The role of geographical ecological studies in identifying diseases linked to UVB exposure and/or vitamin D

Using a variety of approaches, researchers have studied the health effects of solar ultraviolet (UV) radiation exposure and vitamin D. This review compares the contributions from geographical ecological studies with those of observational studies and clinical trials. Health outcomes discussed were based on the author's knowledge and include anaphylaxis/food allergy, atopic dermatitis and eczema, attention deficit hyperactivity disorder, autism, back pain, cancer, dental caries, diabetes mellitus type 1, hypertension, inflammatory bowel disease, lupus, mononucleosis, multiple sclerosis, Parkinson disease, pneumonia, rheumatoid arthritis, and sepsis. Important interactions have taken place between study types; sometimes ecological studies were the first to report an inverse correlation between solar UVB doses and health outcomes such as for cancer, leading to both observational studies and clinical trials. In other cases, ecological studies added to the knowledge base. Many ecological studies include other important risk-modifying factors, thereby minimizing the chance of reporting the wrong link. Laboratory studies of mechanisms generally support the role of vitamin D in the outcomes discussed. Indications exist that for some outcomes, UVB effects may be independent of vitamin D. This paper discusses the concept of the ecological fallacy, noting that it applies to all epidemiological studies.

Significant association between vitamin D deficiency and sepsis: a systematic review and meta-analysis

Background

A number of observational studies have found an association between low vitamin D levels and risk of sepsis. We conducted a systematic review and meta-analysis to determine the overall estimate of risk.

Methods

This was a systematic review and meta-analysis conducted by online searches (CENTRAL, PubMed/MEDLINE, and EMBASE) was registered in PROSPERO (CRD42014014767). Primary outcome was incidence, prevalence, relative risk or odds ratio of having sepsis or bloodstream infection between patients with vitamin D deficiency and controls.

Results

The initial search yielded 647 articles. Twenty-one articles underwent full-length review and data were extracted from 10 observational studies. Pooled odds ratio of sepsis in participants with vitamin D deficiency was 1.78 (95 % confidence interval [CI] = 1.55 to 2.03, p < 0.01) compared with controls in studies that reported participant numbers and was 1.45 (95 % CI = 1.26 to 1.66, p < 0.01) in studies that reported an adjusted odds ratio of vitamin D deficiency for developing sepsis. Statistical between-study heterogeneity was low (I² = 0 % and 5 %, respectively). Standardized mean difference of 25-hydroxyvitamin D levels in patients with sepsis and controls was −0.24 (95 % CI = −0.49 to 0.00, p = 0.05) and lower in the sepsis group compared with non-sepsis or control participants. The statistical between-study heterogeneity (I²) was 0 %.

Conclusion

Vitamin D deficiency were associated with an increased susceptibility of sepsis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-015-0063-3) contains supplementary material, which is available to authorized users.

An update on the association of vitamin D deficiency with common infectious diseases

Vitamin D plays an important role in modulating the immune response to infections. Deficiency of vitamin D is a common condition, affecting both the general population and patients in health care facilities. Over the last decade, an increasing body of evidence has shown an association between vitamin D deficiency and an increased risk for acquiring several infectious diseases, as well as poorer outcomes in vitamin D deficient patients with infections. This review details recent developments in understanding the role of vitamin D in immunity, the antibacterial actions of vitamin D, the association between vitamin D deficiency and common infections (like sepsis, pneumonia, influenza, methicillin-resistant Staphylococcus aureus, human immunodeficiency virus type-1 (HIV), and hepatitis C virus (HCV)), potential therapeutic implications for vitamin D replacement, and future research directions.