Effect of vitamin D3 on asthma treatment failures in adults with symptomatic asthma and lower vitamin D levels: the VIDA randomized clinical trial

U-shaped association between 25-hydroxyvitamin D concentration and the prevalence of asthma in the overweight and obese U.S. population

INTRODUCTION

Vitamin D supplementation has shown promise in averting asthma. However, the association between 25(OH)D levels and asthma prevention in various demographic groups remains inconclusive. Here, we explore this relationship in the context of overweight and obese individuals in the United States.

METHODS

We scrutinized cross-sectional data derived from the National Health and Nutrition Examination Survey conducted between 2007 and 2018. This dataset encompasses comprehensive information about asthma patients with a body mass index greater than 25 kg/m2, in addition to data regarding 25(OH)D concentration and other pertinent variables. Among the 3889 participants, 16.2% (631/3889) reported a history of asthma, constituting 1765 (45.4%) males and 2124 (54.6%) females. The median age was 56.0 years, with a standard deviation of 16.0 years. We conducted restricted cubic spline (RCS) regression analysis to assess the correlation between 25(OH)D levels and asthma.

RESULTS

After adjusting for confounders, compared to individuals with lower 25-hydroxyvitamin D concentration (group1 ≤ 46.6 nmol/L), the adjusted odds ratios (OR) for asthma in group2 (46.7-62 nmol/L), group3 (62.1-78.2 nmol/L), and group4 (≥78.3 nmol/L) were 0.68 (95% CI: 0.49-0.94, p < 0.021), 0.65 (95% CI: 0.47-0.88, p < 0.006), and 0.83 (95% CI: 0.61-1.12, p < 0.22), respectively. Restricted cubic spline (RCS) regression analysis revealed a nonlinear U-shaped curve (p = 0.017) with an inflection point at approximately 84.95 nmol/L.

CONCLUSIONS

High levels of 25(OH)D are correlated with a diminished prevalence of asthma among overweight and obese individuals in the United States.

The effects of vitamin D supplementation on inflammatory biomarkers in patients with asthma: a systematic review and meta-analysis of randomized controlled trials

Background

While the association between vitamin D and several inflammatory biomarkers in asthma patients has been extensively reported, it remains unclear whether supplementation modifies these biomarkers. This review aims to evaluate the impact of vitamin D supplementation on inflammatory biomarkers measured in vivo in individuals with asthma.

Methods

We conducted a systematic review of randomized controlled trials (RCTs) published until November 2022 in six electronic databases evaluating the impact of vitamin D supplementation (any dose, form, administration route, frequency, or duration) compared to placebo in children or adults. The two co-primary outcomes were serum IgE and blood eosinophils reported at the endpoint. Secondary outcomes included other markers of type 2 inflammation (e.g., sputum eosinophils, fractional exhaled nitric oxide, etc.), anti-inflammatory biomarkers (e.g., interleukin (IL)-10, etc.), markers of non-type 2 inflammation (e.g., high-sensitivity C-reactive protein, etc.), and non-specific biomarkers (e.g., macrophages, etc.). Data were aggregated using fixed or random effect models.

Results

Thirteen RCTs (5 in adults, 5 in pediatric patients, and 3 in mixed age groups) testing doses of vitamin D supplementation ranging from 800 to 400,000 IU over periods of 6 weeks to 12 months were included. Eight studies provided data on serum IgE and four on blood eosinophils. As secondary outcomes, three studies reported on sputum eosinophils, four on FeNO, five on serum IL-10, and two on airway IL-10. Compared to placebo, vitamin D supplementation had no significant effect on serum IgE (Mean difference [MD] [95% CI]: 0.06 [-0.13, 0.26] IU/mL), blood eosinophils (MD [95% CI]: - 0.02 [-0.11, 0.07] 103/μL), or FeNO (MD [95% CI]: -4.10 [-10.95, 2.75] ppb) at the endpoint. However, the vitamin D supplementation group showed higher serum IL-10 levels compared to placebo (MD [95% CI]: 18.85 [1.11, 36.59] pg/ml) at the endpoint. Although data could not be aggregated, narrative synthesis suggested no significant effect of supplementation on sputum eosinophils and IL-10 in both sputum and exhaled breath condensate, at the endpoint.

Conclusion

Vitamin D supplementation in individuals with asthma was not associated with lower inflammatory biomarkers related to type 2 inflammation. However, it was significantly associated with higher serum IL-10 compared to placebo.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022365666.

Vitamin D Oral Replacement in Children With Obesity Related Asthma: VDORA1 Randomized Clinical Trial

Children with asthma and obesity are more likely to have lower vitamin D levels, but the optimal replacement dose is unknown in this population. The objective of this study is identifying a vitamin D dose in children with obesity-related asthma that safely achieves serum vitamin D levels of ≥ 40 ng/mL. This prospective multisite randomized controlled trial recruited children/adolescents with asthma and body mass index ≥ 85% for age/sex. Part 1 (dose finding), evaluated 4 oral vitamin D regimens for 16 weeks to identify a replacement dose that achieved serum vitamin D levels ≥ 40 ng/mL. Part 2 compared the replacement dose calculated from part 1 (50,000 IU loading dose with 8,000 IU daily) to standard of care (SOC) for 16 weeks to identify the proportion of children achieving target serum 25(OH)D level. Part 1 included 48 randomized participants. Part 2 included 64 participants. In Part 1, no SOC participants achieved target serum level, but 50-72.7% of participants in cohorts A-C achieved the target serum level. In part 2, 78.6% of replacement dose participants achieved target serum level compared with none in the SOC arm. No related serious adverse events were reported. This trial confirmed a 50,000 IU loading dose plus 8,000 IU daily oral vitamin D as safe and effective in increasing serum 25(OH)D levels in children/adolescents with overweight/obesity to levels ≥ 40 ng/mL. Given the critical role of vitamin D in many conditions complicating childhood obesity, these data close a critical gap in our understanding of vitamin D dosing in children.

Effect of dietary interventions on markers of type 2 inflammation in asthma: A systematic review

INTRODUCTION

Type 2 (T2) inflammation is a key mechanism in the pathophysiology of asthma. Diet may have immunomodulatory effects, and a role for diet in T2 inflammation has been suggested in the literature. Indeed, diet and food allergies play a role in children with atopic asthma, but less is known about diet in relation to adult asthma, which is often non-atopic.

OBJECTIVE

To review the effect of dietary interventions on markers of T2 inflammation in adults with asthma.

METHODS

The databases PubMed, Embase, Cochrane Library, and CINAHL were searched for eligible studies until December 2022. We included studies of all types of foods, nutrients, diets or supplements, either as an exposure or as an intervention, in adults and adolescents with asthma. Outcomes of interest included the T2 biomarkers FeNO, eosinophils, IL-4, IL-5, IL-13, eosinophil cationic protein and eosinophil peroxidase. The methodological quality of eligible studies was systematically evaluated, and the results were summarised according to dietary clusters.

RESULTS

The systematic search identified studies on the dietary clusters antioxidants (n = 14), fatty acids, (n = 14), Mediterranean-style diets (n = 5), phytotherapy (n = 7), prebiotics & probiotics (n = 8), vitamin D (n = 7), and other dietary factors (n = 5). Studies within the phytotherapy and omega-3 poly-unsaturated fatty acids (PUFA) clusters showed possible improvements in T2 inflammation. Furthermore, we found little evidence for an effect of antioxidants, prebiotics & probiotics, and Mediterranean-style diets on T2 inflammation. However, heterogeneity in study protocols, methodological shortcomings and limited power of almost all studies make it difficult to fully determine the impact of different dietary approaches on T2 inflammation in asthma.

CONCLUSIONS

Overall, the current evidence does not support a specific dietary intervention to improve T2 inflammation in asthma. Interventions involving phytotherapy and omega-3 PUFA currently have the best evidence and warrant further evaluation in well-designed and adequately powered studies, while taking into account T2-high phenotypes of asthma.

Management of the pediatric patient with asthma and obesity

Asthma and obesity are 2 of the most significant chronic diseases of childhood. Both are major public health problems that have been increasing in prevalence. Obesity increases the risk of developing asthma in children, and in children with asthma, obesity increases asthma severity and morbidity. The nature of this relationship is complex and not fully understood, but some pediatric patients with "obesity-related asthma" may represent a phenotype that differs from the more classical, atopic pediatric asthma. In this review, we investigate and discuss some of the currently available literature regarding treatment for asthma complicated by obesity in the pediatric population. We cover the importance of healthy lifestyle modifications, management of obesity-related comorbidities, and the potential role of nutritional supplementation or modification. We then review recent literature, mostly in adults, investigating the potential role of obesity or diabetes medications in the management of patients with asthma who have obesity. Finally, we discuss some of the necessary next steps before these potential new treatments can be considered as part of the standard clinical management of asthma.

Vitamin D and idiopathic pulmonary fibrosis: a two-sample mendelian randomization study

BACKGROUND

A prospective study of multiple small samples found that idiopathic pulmonary fibrosis (IPF) is often accompanied by a deficiency in Vitamin D levels. However, the causal relationship between the two remains to be determined. Therefore, our study aims to investigate the causal effect of serum 1,25-hydroxyvitamin D (25(OH)D) on the risk of IPF through a two-sample Mendelian randomization (MR) analysis.

METHODS

Through data analysis from two European ancestry-based genome-wide association studies (GWAS), including 401,460 individuals for 25(OH)D levels and 1028 individuals for IPF, we primarily employed inverse-variance weighted (IVW) to assess the causal effect of 25(OH)D levels on IPF risk. MR-Egger regression test was used to determine pleiotropy, and Cochran's Q test was conducted for heterogeneity testing. Leave-one-out analysis was conducted to examine the robustness of the results.

RESULTS

158 SNPs related to serum 25(OH)D were used as instrumental variables (IVs). The MR analyses revealed no evidence supporting a causal association between the level of circulating 25(OH)D and the risk of IPF. The IVW method [OR 0.891, 95%CI (0.523-1.518), P = 0.670]; There was no significant level of heterogeneity, pleiotropy and bias in IVs. Cochran's Q test for heterogeneity (MR Egger P = 0.081; IVW P = 0.089); MR-Egger regression for pleiotropy (P = 0.774).

CONCLUSIONS

This MR Study suggests that genetically predicted circulating vitamin D concentrations in the general population are not causally related to IPF.

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.]

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Therapeutic Potential of Vitamin D in Management of Asthma: A Literature Review

Asthma, a prevalent chronic respiratory illness, affects a substantial number of individuals worldwide, with an estimated occurrence of 358 million cases. Evidence for the benefits of vitamin D in treating asthma is ambiguous and contradictory. The goal of this review article is to emphasize the value of vitamin D supplementation for people with asthma. Medical subject headings (MeSH) terminology was used to search the PubMed Central, MEDLINE, and PubMed databases for articles on vitamin D supplementation in asthma patients. We selected a comprehensive range of academic writing examples published in English, encompassing various types of texts. The study included a total of 37 papers, of which 18 were randomized controlled trials (RCTs) and five were meta-analyses. The use of a corticosteroid, with or without the inclusion of an adrenergic receptor agonist, improves the disease's symptoms, but it is unable to halt the long-term decline in lung function. Over the past 20 years, vitamin D has developed into a potent immunomodulator, influencing both immunological and structural cells, most notably airway smooth muscle cells. Among adults with low 25-hydroxyvitamin D levels, the administration of vitamin D supplements was found to have positive effects in a reduction in the likelihood of asthma exacerbations requiring systemic corticosteroids. The provision of vitamin D supplements during pregnancy significantly reduces the risk of asthma in babies. Both children and adults with inadequate vitamin D levels who have been given vitamin D supplements have shown evident preventive effects against asthma. Therefore, we conclude there should be a lower threshold for prescribing vitamin D to patients with asthma who are vitamin D deficient.

Vitamin D Role in Childhood Mite Allergy and Allergen Immunotherapy (AIT)

The post hoc analysis presented here aimed to address the influence of endogenous vitamin D in the immunological mechanism underlying effective mite allergoid immunotherapy (AIT). Previously, we have shown that in allergic children, after 12 months of this immunoactive treatment, functionally potentiated memory regulatory T cells are identified. Indeed, AIT is the only known treatment that is able to reshape the detrimental immune response against the allergen into a non-noxious one. Besides, VD is widely considered an immunoregulatory molecule that is endogenously produced and exogenously provided by foods and supplements that might interact with the AIT mechanism, thus affecting its outcome. Therefore, a post hoc analysis of the clinical and immunological data from three different cohorts of allergic patients was performed. One cohort (N = 70) was on a standard symptom-controlling pharmacological treatment, while the other two (N = 60 and N = 35) were treated with AIT for 12 months. In the first cohort, a lower mean endogenous VD level (<22 ng/mL) was observed along with worse symptoms and a greater use of medications. Remarkably, the comparison between two sub-cohorts of patients with a serum VD level above (N = 32) or below (N = 28) a cut-off value set at the mean value (27 ng/mL) revealed that optimal improvement of all clinical and immune parameters was achieved (as expected from effective AIT), irrespective of the VD level. Notably, the third analysis, carried out on one cohort of AIT patients that were also concomitantly taking VD3 as a food supplement (N = 19), was distinguished by an uppermost overall treatment outcome (the amelioration of symptoms, the lowest medication requirements, and a reduction in the total and allergen-specific IgE levels), as well as an increase in the allergen-specific tolerogenic memory T regulatory cells. These findings suggest that the endogenous VD level affects the allergy severity and allergen immunotherapy effectiveness. In addition, VD3 might be investigated as an add-on supplement to obtain the best out of immunotherapy in VD-deficient/-insufficient allergic patients. The immunogenic, but low-allergenic, mite allergoid used as the bioactive agent might have contributed to minimizing the allergic response and highlighting the immunological effects described here.

Prevention of COVID-19 with oral vitamin D supplemental therapy in essential healthcare teams (PROTECT): protocol for a multicentre, triple-blind, randomised, placebo-controlled trial

INTRODUCTION

In the COVID-19 pandemic, healthcare workers (HCWs) were at high risk of infection due to their exposure to COVID infections. HCWs were the backbone of our healthcare response to this pandemic; every HCW withdrawn or lost due to infection had a substantial impact on our capacity to deliver care. Primary prevention was a key approach to reduce infection. Vitamin D insufficiency is highly prevalent in Canadians and worldwide. Vitamin D supplementation has been shown to significantly decrease the risk of respiratory infections. Whether this risk reduction would apply to COVID-19 infections remained to be determined. This study aimed to determine the impact of high-dose vitamin D supplementation on incidence of laboratory-confirmed COVID-19 infection rate and severity in HCWs working in high COVID incidence areas.

METHODS AND ANALYSIS

PROTECT was a triple-blind, placebo-controlled, parallel-group multicentre trial of vitamin D supplementation in HCWs. Participants were randomly allocated in a 1:1 ratio in variable block size to intervention (one oral loading dose of 100 000 IU vitamin D₃+10 000 IU weekly vitamin D₃) or control (identical placebo loading dose+weekly placebo). The primary outcome was the incidence of laboratory-confirmed COVID-19 infection, documented by RT-qPCR on salivary (or nasopharyngeal) specimens obtained for screening or diagnostic purposes, as well as self-obtained salivary specimens and COVID-19 seroconversion at endpoint. Secondary outcomes included disease severity; duration of COVID-19-related symptoms; COVID-19 seroconversion documented at endpoint; duration of work absenteeism; duration of unemployment support; and adverse health events. The trial was terminated prematurely, due to recruitment difficulty.

ETHICS AND DISSEMINATION

This study involves human participants and was approved by the Research Ethics Board (REB) of the Centre hospitalier universitaire (CHU) Sainte-Justine serving as central committee for participating institutions (#MP-21-2021-3044). Participants provided written informed consent to participate in the study before taking part. Results are being disseminated to the medical community via national/international conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

https://clinicaltrials.gov/ct2/show/NCT04483635.

Normal 24-hour Urine Calcium Concentrations after Long-term Daily Oral Intake of Vitamin D in Doses Ranging from 5000 to 50,000 International Units in 14 Adult Hospitalized Psychiatric Patients

Many controversies exist regarding vitamin D₃ supplementation. These include not only diseases that are responsive to vitamin D supplementation, but also the long-term safety of prolonged daily oral vitamin D₃ intake above 4000 to 10,000 International Units (IU). In particular, supplementation levels that do not result in adverse events, and the upper limits of safe serum 25-hydroxyvitamin D (25OHD) concentrations. Adverse reactions reported to occur with excessive vitamin D intake include hypercalcemia, renal failure, calcium crystal formation, undetectable parathyroid hormone concentrations, and hypercalciuria, all of which are reported to be reversible. To address the long-term safety of vitamin D supplementation, we previously reported data from patients in our hospital who have been voluntarily supplemented with vitamin D₃ ranging from 5,000 to 10,000 IU/day since July 2011 as a standard of care for the prevention and treatment of vitamin D deficiency. Historically 90% of patients have agreed to daily supplementation, with most taking 10,000 IU/day. These data indicate no evidence for hypercalcemia, renal failure, calcium crystal formation, nephrolithiasis. or undetectable parathyroid hormone concentrations in patients taking 5,000 or 10,000 IU/day for extended periods of time. As another measure for potential vitamin D toxicity, we retrospectively assessed 24-hour urine calcium excretion in 14 individuals on long-term daily oral vitamin D intake ranging from 5,000 to 50,000 IU/day to further assess the safety of supplementation using these doses. This included patients taking either 5,000 (4), 10,000 (9), or 50,000 (1) IU/day. Time on supplementation ranged from 10 to 102 months. A patient taking 400 IU/day and getting frequent sun exposure was also included. All fifteen 24-hour urine calcium measurements were normal. The current findings complement our experience with over 7000 patients in the past 13 years, indicating that prolonged daily oral intake of vitamin D₃ ranging from 5000 to 10,000 IU/day is safe.

Effects of Oxidative Stress on Airway Epithelium Permeability in Asthma and Potential Implications for Patients with Comorbid Obesity

20 million adults and 4.2 million children in the United States have asthma, a disease resulting in inflammation and airway obstruction in response to various factors, including allergens and pollutants and nonallergic triggers. Obesity, another highly prevalent disease in the US, is a major risk factor for asthma and a significant cause of oxidative stress throughout the body. People with asthma and comorbid obesity are susceptible to developing severe asthma that cannot be sufficiently controlled with current treatments. More research is needed to understand how asthma pathobiology is affected when the patient has comorbid obesity. Because the airway epithelium directly interacts with the outside environment and interacts closely with the immune system, understanding how the airway epithelium of patients with asthma and comorbid obesity is altered compared to that of lean asthma patients will be crucial for developing more effective treatments. In this review, we discuss how oxidative stress plays a role in two chronic inflammatory diseases, obesity and asthma, and propose a mechanism for how these conditions may compromise the airway epithelium.

Pathogenesis of Nasal Polyposis: Current Trends

Chronic Rhinosinusitis (CRS) is characterized by edema of the sub-epithelial layers, but, only specific types of CRS are developing polyps. Nasal polyposis may develop under different pathogenetic mechanisms rendering the typical macroscopic classification of CRS, with or without nasal polyps, rather deficient. Currently, we approach nasal polyposis, in terms of diagnosis and treatment, according to its endotype, which means that we focus on the specific cells and cytokines that are participating in its pathogenesis. It appears that the molecular procedures that contribute to polyp formation, initiating with a Th-2 response of the adaptive immune system, are local phenomena occurring in the sub-epithelial layers of the mucosa. Several hypotheses are trying to approach the etiology that drives the immune response towards Th-2 type. Extrinsic factors, like fungi, Staphylococcus superantigens, biofilms, and altered microbiome can contribute to a modified and intense local reaction of the immune system. Some hypotheses based on intrinsic factors like the elimination of Treg lymphocytes, low local vitamin-D levels, high levels of leukotrienes, epithelial to mesenchymal transition (EMT) induced by hypoxia, and altered levels of NO, add pieces to the puzzle of the pathogenesis of nasal polyposis. Currently, the most complete theory is that of epithelial immune barrier dysfunction. Intrinsic and extrinsic conditions can damage the epithelial barrier rendering sub-epithelial layers more vulnerable to invasion by pathogens that trigger a Th-2 response of the adaptive immune system. Th2 cytokines, subsequently, induce the accumulation of eosinophils and IgE together with the remodeling of the stroma in the sub-epithelial layers leading, eventually, to the formation of nasal polyps.

Vitamin D: 100 years of discoveries, yet controversy continues

Over the past 100 years, many major breakthroughs and discoveries have occurred in relation to vitamin D research. These developments include the cure of rickets in 1919, the discovery of vitamin D compounds, advances in vitamin D molecular biology, and improvements in our understanding of endocrine control of vitamin D metabolism. Furthermore, recommended daily allowances for vitamin D have been established and large clinical trials of vitamin D, aimed at clarifying the effect of Vitamin D in the prevention of multiple diseases, have been completed. However, disappointingly, these clinical trials have not fulfilled the expectations many had 10 years ago. In almost every trial, various doses and routes of administration did not show efficacy of vitamin D in preventing fractures, falls, cancer, cardiovascular diseases, type 2 diabetes, asthma, and respiratory infections. Although concerns about side-effects of long-term high-dose treatments, such as hypercalcaemia and nephrocalcinosis, have been around for four decades, some trials from the past 5 years have had new and unexpected adverse events. These adverse events include increased fractures, falls, and hospitalisations in older people (aged >65 years). Several of these clinical trials were powered appropriately for a primary outcome but did not include dose response studies and were underpowered for secondary analyses. Furthermore, more attention should be paid to the safety of high doses of vitamin D supplementation, particularly in older people. In addition, despite universal recommendations by osteoporosis societies for combining calcium supplements with vitamin D there remains insufficient data about their efficacy and effect on fracture risk in the highest risk groups. More trials are needed for people with severe vitamin D deficiency (ie, serum 25-hydroxyvitamin D <25nmol/L [10ng/mL]). In this Personal View, we summarise and discuss some of the major discoveries and controversies in the field of vitamin D.

Apigenin ameliorates non-eosinophilic inflammation, dysregulated immune homeostasis and mitochondria-mediated airway epithelial cell apoptosis in chronic obese asthma via the ROS-ASK1-MAPK pathway

BACKGROUND

Obese asthma is one of the important asthma phenotypes that have received wide attention in recent years. Excessive oxidative stress and different inflammatory endotypes may be important reasons for the complex symptoms, frequent aggravation, and resistance to traditional treatments of obese asthma. Apigenin (API), is a flavonoid natural small molecule compound with good anti-inflammatory and antioxidant activity in various diseases and proved to have the potential efficacy to combat obese asthma.

METHODS

In vivo, this study fed C57BL/6 J mice with high-fat diets(HFD)for 12 weeks and then stimulated them with OVA for 6 weeks to establish a model of chronic obese asthma, while different doses of oral API or dexamethasone were used for therapeutic interventions. In vitro, this study used HDM to stimulate human bronchial cells (HBEs) to establish the model and intervened with API or Selonsertib (SEL).

RESULTS

This study clarified that OVAinduced a type of mixed granulocytic asthma with elevated neutrophils and eosinophils in obese male mice fed with long-term HFD, which also exhibited mixed TH17/TH1/TH2 inflammation. Apigenin effectively suppressed this complex inflammation and acted as a regulator of immune homeostasis. Meanwhile, apigenin reduced AHR, inflammatory cell infiltration, airway epithelial cell apoptosis, airway collagen deposition, and lung oxidative stress via the ROS-ASK1-MAPK pathway in an obese asthma mouse model. In vitro, this study found that apigenin altered the binding status of TRAF6 to ASK1, inhibited ASK1 phosphorylation, and protected against ubiquitin-dependent degradation of ASK1, suggesting that ROS-activated ASK1 may be an important target for apigenin to exert anti-inflammatory and anti-apoptotic effects. To further verify the intervention mechanism, this study clarified that apigenin improved cell viability and mitochondrial function and inhibited apoptosis by interfering with the ROS-ASK1-MAPK pathway.

CONCLUSIONS

This study demonstrates for the first time the therapeutic effect of apigenin in chronic obese asthma and further clarifies its potential therapeutic targets. In addition, this study clarifies the specificity of chronic obese asthma and provides new options for its treatment.

Long-term supplementation with 3200 to 4000 IU of vitamin D daily and adverse events: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

The upper tolerable intake level for vitamin D in the general population has been set at 4000 international units (IU) daily, but considerable uncertainty remains. We summarized reported harmful effects of a daily vitamin D supplement of 3200-4000 IU in trials lasting ≥ 6 months.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials in several databases and identified 22 trials reporting safety data. Parameters of calcium metabolism, falls, hospitalization, and mortality were assessed.

RESULTS

The selected trials comprised a total number of 12,952 participants. All trials used supplemental vitamin D₃. The relative risk (RR) of hypercalcemia in the vitamin D vs. control arm was 2.21 (95%CI: 1.26-3.87; 10 studies), with a vitamin D-induced frequency of hypercalcemia of 4 cases per 1000 individuals. Subgroup analysis in trials with > 100 and ≤ 100 study participants revealed an RR of 2.63 (95%CI: 1.30-5.30; 7 studies) and 0.80 (95%CI: 0.24-2.62; 3 studies), respectively (P_interaction = 0.06). Risks of falls and hospitalization were also significantly increased in the vitamin D arm with an RR of 1.25 (95%CI: 1.01-1.55; 4 studies) and 1.16 (95%CI: 1.01-1.33; 7 studies), respectively. Risks of hypercalciuria, kidney stones, and mortality did not differ significantly between study arms. Quality assessment revealed high risk of incomplete reporting of safety-related outcome data.

CONCLUSION

Supplemental vitamin D doses of 3200-4000 IU/d appear to increase the risk of hypercalcemia and some other adverse events in a small proportion of individuals, indicating that this dose is not completely safe. In future studies, rigorous reporting of safety-related outcomes is needed when using moderately high doses of vitamin D.

Vitamin D for the management of asthma

BACKGROUND

Since the previous Cochrane Review on this topic in 2016, debate has continued surrounding a potential role for vitamin D in reducing risk of asthma exacerbation and improving asthma control. We therefore conducted an updated meta-analysis to include data from new trials completed since this date.

OBJECTIVES

To evaluate the effectiveness and safety of administration of vitamin D or its hydroxylated metabolites in reducing the risk of severe asthma exacerbations (defined as those requiring treatment with systemic corticosteroids) and improving asthma symptom control.

SEARCH METHODS

We searched the Cochrane Airways Group Trial Register and reference lists of articles. We contacted the authors of studies in order to identify additional trials. Date of last search: 8 September 2022.

SELECTION CRITERIA

We included double-blind, randomised, placebo-controlled trials of vitamin D in children and adults with asthma evaluating exacerbation risk or asthma symptom control, or both.

DATA COLLECTION AND ANALYSIS

Four review authors independently applied study inclusion criteria, extracted the data, and assessed risk of bias. We obtained missing data from the authors where possible. We reported results with 95% confidence intervals (CIs). The primary outcome was the incidence of severe asthma exacerbations requiring treatment with systemic corticosteroids. Secondary outcomes included the incidence of asthma exacerbations precipitating an emergency department visit or requiring hospital admission, or both, end-study childhood Asthma Control Test (cACT) or Asthma Control Test (ACT) scores, and end-study % predicted forced expiratory volume in one second (FEV1). We performed subgroup analyses to determine whether the effect of vitamin D on risk of asthma exacerbation was modified by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, form of vitamin D given, and age of participants.

MAIN RESULTS

We included 20 studies in this review; 15 trials involving a total of 1155 children and five trials involving a total of 1070 adults contributed data to analyses. Participant ages ranged from 1 to 84 years, with two trials providing data specific to participants under five years (n = 69) and eight trials providing data specific to participants aged 5 to 16 (n = 766). Across the trials, 1245 participants were male and 1229 were female, with two studies not reporting sex distribution. Fifteen trials contributed to the primary outcome analysis of exacerbations requiring systemic corticosteroids. The duration of trials ranged from three to 40 months; all but two investigated effects of administering cholecalciferol (vitamin D3). As in the previous Cochrane Review, the majority of participants had mild to moderate asthma, and profound vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25 nmol/L) at baseline was rare. Administration of vitamin D or its hydroxylated metabolites did not reduce or increase the proportion of participants experiencing one or more asthma exacerbations treated with systemic corticosteroids (odds ratio (OR) 1.04, 95% CI 0.81 to 1.34; I2 = 0%; 14 studies, 1778 participants; high-quality evidence). This equates to an absolute risk of 226 per 1000 (95% CI 185 to 273) in the pooled vitamin D group, compared to a baseline risk of 219 participants per 1000 in the pooled placebo group. We also found no effect of vitamin D supplementation on the rate of exacerbations requiring systemic corticosteroids (rate ratio 0.86, 95% CI 0.62 to 1.19; I2 = 60%; 10 studies, 1599 participants; high-quality evidence), or the time to first exacerbation (hazard ratio 0.82, 95% CI 0.59 to 1.15; I2 = 22%; 3 studies, 850 participants; high-quality evidence). Subgroup analysis did not reveal any evidence of effect modification by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, or age. A single trial investigating administration of calcidiol reported a benefit of the intervention for the primary outcome of asthma control. Vitamin D supplementation did not influence any secondary efficacy outcome meta-analysed, which were all based on moderate- or high-quality evidence. We observed no effect on the incidence of serious adverse events (OR 0.89, 95% CI 0.56 to 1.41; I2 = 0%; 12 studies, 1556 participants; high-quality evidence). The effect of vitamin D on fatal asthma exacerbations was not estimable, as no such events occurred in any trial. Six studies reported adverse reactions potentially attributable to vitamin D. These occurred across treatment and control arms and included hypercalciuria, hypervitaminosis D, kidney stones, gastrointestinal symptoms and mild itch. In one trial, we could not ascertain the total number of participants with hypercalciuria from the trial report. We assessed three trials as being at high risk of bias in at least one domain; none of these contributed data to the analysis of the outcomes reported above. Sensitivity analyses that excluded these trials from each outcome to which they contributed did not change the null findings.

AUTHORS' CONCLUSIONS

In contrast to findings of our previous Cochrane Review on this topic, this updated review does not find evidence to support a role for vitamin D supplementation or its hydroxylated metabolites to reduce risk of asthma exacerbations or improve asthma control. Participants with severe asthma and those with baseline 25(OH)D concentrations < 25 nmol/L were poorly represented, so further research is warranted here. A single study investigating effects of calcidiol yielded positive results, so further studies investigating effects of this metabolite are needed.

Evaluating the effects of vitamin D Level on airway obstruction in two asthma endotypes in humans and in two mouse models with different intake of vitamin D during early-life

Introduction

Asthma is primarily divided into two categories: type 2 (T2-high) and non-type 2 (T2-low). A relationship between asthma severity and vitamin D deficiency has been identified, but its impact on each asthma endotype remains unknown.

Methods

We clinically examined the influence of vitamin D on patients with T2-high (n = 60) or T2-low asthma (n = 36) compared with controls (n = 40). Serum 25(OH)D levels, inflammatory cytokines and spirometry were measured. Mouse models were then used to further analyze the effects of vitamin D on both asthmatic endotypes. BALB/c mice were fed with vitamin D-deficient (LVD), -sufficient (NVD), or -supplemented diets (HVD) throughout lactation and offspring followed the same diet after weaning. Offspring were sensitized/challenged with ovalbumin (OVA) to establish "T2-high" asthma or OVA combined with ozone exposure (OVA + ozone) to induce "T2-low" asthma. Spirometry and serum, bronchoalveolar lavage fluid (BALF), and lung tissues were analyzed.

Results

Serum 25(OH)D levels were decreased in asthmatic patients compared with controls. Patients with vitamin D deficiency (Lo) had varying degrees of elevation of the pro-inflammatory cytokines IL-5, IL-6, and IL-17A, decreased expression of the anti-inflammatory cytokine IL-10, and altered forced expiratory volume in the first second as a percentage of predicted value (FEV₁%pred) in both asthmatic endotypes. Vitamin D status had a stronger correlation with FEV₁%pred in T2-low asthma than T2-high asthma, and 25(OH)D level was only positively linked to maximal mid-expiratory flow as a percentage of predicted value (MMEF%pred) in the T2-low group. Inflammation, hyperresponsiveness, and airway resistance (R_L) was increased in both asthma models compared with controls while vitamin D deficiency further increased airway inflammation and airway obstruction. These findings were particularly prominent in T2-low asthma.

Discussion

The potential function and mechanisms of vitamin D and both asthma endotypes should be studied individually, and further analysis of the potential signaling pathways involved with vitamin D on T2-low asthma is warranted.

Efficacy of vitamin D supplementation on COPD and asthma control: A systematic review and meta-analysis

Background

The role of vitamin D (VD) in the management of chronic obstructive pulmonary disease (COPD) and asthma remains largely undetermined. In the present meta-analysis, we aimed to comprehensively investigate the efficacy of VD in the treatment of COPD and asthma according to the latest update.

Methods

The PubMed, Embase, and Cochrane Library databases were searched from their inception to June 2, 2022. Randomized controlled trials (RCTs) comparing the efficacy of VD with placebo against COPD or asthma were included.

Results

A total of 11 RCTs consisting of 1183 COPD patients and 19 RCTs consisting of 2025 asthmatic patients were finally included. As for pulmonary function, FEV1/FVC was not changed significantly, while FEV1% was improved in the VD group. In the asthma subgroup, FEV1% was not changed significantly, while FEV1/FVC was improved in the VD group. For the questionnaire and rating scale, the mMRC (modified Medical Research Council) dyspnoea scale score for COPD and ACT (Asthma Control Test) score for asthma were not significantly changed, while the SGRQ (St. George's Respiratory Questionnaire) score for COPD was improved in the VD group. For inflammation indicators, IL-6 and IL-10 were statistically equivalent between the VD and placebo groups, while IgE, IL-5, and IL-10 (baseline VD deficiency subgroup) were improved in the VD group. The exacerbation, length of hospital stays, and mortality were statistically equivalent between the two groups.

Conclusions

VD supplementation improved the indicators of asthma and COPD, especially in pulmonary function, SGRQ scores, IL-5, and IgE.

Registration

The protocol could be found at PROSPERO with the registration number of CRD42020218058.

Vitamin D status and asthma, lung function, and hospitalization among British adults

Background

Vitamin D has been known to be associated with asthma. However, the association between vitamin D status and asthma, lung function as well as hospitalization among adults remains unclear.

Objective

To investigate the role of serum vitamin D in asthma prevalence, lung function, and asthma control in adults.

Methods

Multivariable logistic regression was applied to assess the relationship between serum vitamin D and asthma prevalence, lung function (FEV1, FVC, and FEV1/FVC), current wheeze, and asthma-linked hospitalizations in a cross-sectional study of 435,040 adults aged 37-73 years old from the UK Biobank.

Results

Compared to vitamin D deficiency, the odds of asthma were decreased by 6.4% [adjusted odds ratio (aOR) = 0.936; 95% CI: 0.911-0.962; p < 0.001] and 9.8% (aOR = 0. 0.902; 95% CI: 0.877-0. 0.927; p < 0.001) in individuals with insufficient and optimal vitamin D concentration, respectively, in the fully adjusted model. In total asthmatic patients, serum vitamin D was obviously and positively related with FEV1 (β = 1.328 ml, 95% CI = 0.575-2.080), FVC (β = 2.018 ml, 95% CI = 1.127-2.908), and FEV1/FVC (β = 0.006%, 95% CI = 0.002-0.010). Asthmatic patients whose vitamin D level was in the deficient category had 9.3-19.9% higher odds of current wheeze than insufficient categories (aOR = 0.907; 95% CI: 0.861-0.957; p < 0.001) and optimal categories (aOR = 0.801; 95% CI: 0.759-0.845; p < 0.001), but the relationship between vitamin D and asthma hospitalization was not significant.

Conclusion

Vitamin D deficiency was related to higher odds of asthma and current wheeze, and lower lung function in a large sample size study of British adults. Our results indicate a potential positive impact of serum vitamin D on asthma occurrence and disease control in adults.

Asthma and Vitamin D Deficiency: Occurrence, Immune Mechanisms, and New Perspectives

Asthma, as a chronic inflammatory condition of the airways, has a considerable prevalence among children. Vitamin D might play a role in asthma pathogenesis by affecting the development of the lung, regulating the immune responses, and remodeling of airway smooth muscle (ASM). Study results on the association between the serum level of vitamin D and asthma severity have suggested a converse relationship between lower vitamin D levels and more severe clinical courses. However, they are not consistent in these findings and have shown insignificant correlations, as well. The possible effects of vitamin D on asthma have led researchers to consider this vitamin a potential prophylactic and therapeutic tool for managing children with variant degrees of asthma. Adding vitamin D to the routine corticosteroid therapy of asthmatic children is another field of interest that has shown promising results. In this narrative review study, we aim to elaborate on the existing knowledge on the role of vitamin D in asthma pathogenesis and prognosis, explain the controversies that exist on the effectiveness of treating patients with vitamin D supplements, and make a general conclusion about how vitamin D actually is linked to asthma in children.

Role of C3a as a Novel Regulator of 25(OH)D3 to 1α,25-Dihydroxyvitamin D3 Metabolism in Upper Airway Epithelial Cells

In patients with chronic rhinosinusitis with nasal polyps, primary human sinonasal epithelial cell (HSNEC) 1α-hydroxylase levels are reduced, as is their ability to metabolize 25-hydroxycholecalciferol [25(OH)D₃] to its active metabolite, 1α,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃]. In this study, we sought to identify the factor responsible for the regulation of HSNEC metabolism of 25(OH)D₃, focusing on C3 and C3a. Multiple inhaled irritants trigger the release of complement components, C3 and C3a, leading to suppression of 1α-hydroxylase levels in HSNECs. Recombinant C3a was able to decrease 1α-hydroxylase and impair 25(OH)D₃ to 1,25(OH)₂D₃ metabolism, while addition of a C3a receptor antagonist restored conversion. Conversely, 1,25(OH)₂D₃ suppressed Aspergillus fumigatus-induced C3 and C3a levels in HSNEC supernatant. Given the ability of 1,25(OH)₂D₃ to modulate LL37 in other cell types, we examined its regulation in HSNECs and relationship to C3a. 1,25(OH)₂D₃ stimulated the secretion of LL37, whereas A. fumigatus and C3a suppressed it. Conversely, LL37 reduced the release of C3/C3a by HSNECs. Lastly, oral steroid use and in vitro dexamethasone application both failed to increase 1α-hydroxylase or reduce C3a levels. In summary, in this article, we describe for the first time a novel relationship between complement activation and local vitamin D metabolism in airway epithelial cells. The presence of elevated C3/C3a in patients with asthma and/or chronic rhinosinusitis with nasal polyps may account for their impaired HSNEC 25(OH)D₃ to 1,25(OH)₂D₃ metabolism and explain why they receive limited therapeutic benefit from oral vitamin D₃ supplementation.

A Meta-Analysis on Vitamin D Supplementation and Asthma Treatment

Background

Vitamin D, as an immunomodulator, may be related to the therapeutic effect of asthma patients, but the research in this area is still controversial. The aim of this meta-analysis was to analyze the role of vitamin D supplementation in the treatment of asthma patients.

Materials and Methods

Randomized Controlled Trials (RCTs) of vitamin D supplementation in asthma were searched in PubMed, EMBASE, and the Cochrane library. Primary outcomes were forced expiratory volume in one second (FEV1), asthma exacerbations, Asthma Control Test scores (ACT scores), and fractional exhaled nitric oxide (FENO).

Results

A total of 10 RCTs were included, including 1,349 patients. Vitamin D supplementation didn't affect the ACT scores (SMD = 0.04, 95% CI = -0.13 to 0.21, P = 0.87), FEV1 (SMD = 0.04, 95% CI = -0.35 to 0.43, P < 0.01) and FENO (SMD = -0.01, 95% CI = -0.22 to 0.20, P = 0.27), but reduced the rate of asthma exacerbations (RR = 0.69, 95% CI = 0.41 to 0.88, P < 0.01), especially in subgroups of children (RR = 0.46, 95% CI = 0.30 to 0.70, P = 0.83) and follow up time less than 6 months (RR = 0.45, 95% CI = 0.32 to 0.63, P = 0.95). Additionally, though there was only one study included in the subgroup, it significantly enhanced FEV1 at the last visit for patients whose FEV1 baseline value was less than 70% (SMD = 0.94, 95% CI = 0.47 to 1.41).

Conclusion

Vitamin D supplementation can reduce asthma exacerbations, especially in children, and within 6 months of follow up time. In addition, vitamin D has a positive effect on improving FEV1 of patients whose FEV1 baseline value is less than 70%, but more RCTs are still needed to support this conclusion.

Systematic Review Registration

[https://inplasy.com], identifier [10.37766/inplasy20 22.6.0049].

Calcifediol for Use in Treatment of Respiratory Disease

Calcifediol is the prohormone of the vitamin D endocrine system (VDES). It requires hydroxylation to move to 1,25(OH)2D3 or calcitriol, the active form that exerts its functions by activating the vitamin D receptor (VDR) that is expressed in many organs, including the lungs. Due to its rapid oral absorption and because it does not require first hepatic hydroxylation, it is a good option to replace the prevalent deficiency of vitamin D (25 hydroxyvitamin D; 25OHD), to which patients with respiratory pathologies are no strangers. Correcting 25OHD deficiency can decrease the risk of upper respiratory infections and thus improve asthma and COPD control. The same happens with other respiratory pathologies and, in particular, COVID-19. Calcifediol may be a good option for raising 25OHD serum levels quickly because the profile of inflammatory cytokines exhibited by patients with inflammatory respiratory diseases, such as asthma, COPD or COVID-19, can increase the degradation of the active metabolites of the VDES. The aim of this narrative revision is to report the current evidence on the role of calcifediol in main respiratory diseases. In conclusion, good 25OHD status may have beneficial effects on the clinical course of respiratory diseases, including COVID-19. This hypothesis should be confirmed in large, randomized trials. Otherwise, a rapid correction of 25(OH)D deficiency can be useful for patients with respiratory disease.

Title: Understanding a Low Vitamin D State in the Context of COVID-19

While a low vitamin D state has been associated with an increased risk of infection by SARS-CoV-2 in addition to an increased severity of COVID-19 disease, a causal role is not yet established. Here, we review the evidence relating to i) vitamin D and its role in SARS-CoV-2 infection and COVID-19 disease ii) the vitamin D status in the Irish adult population iii) the use of supplemental vitamin D to treat a deficient status and iv) the application of the Bradford-Hill causation criteria. We conclude that reverse causality probably makes a minimal contribution to the presence of low vitamin D states in the setting of COVID-19. Applying the Bradford-Hill criteria, however, the collective literature supports a causal association between low vitamin D status, SARS-CoV-2 infection, and severe COVID-19 (respiratory failure, requirement for ventilation and mortality). A biologically plausible rationale exists for these findings, given vitamin D's role in immune regulation. The thresholds which define low, deficient, and replete vitamin D states vary according to the disease studied, underscoring the complexities for determining the goals for supplementation. All are currently unknown in the setting of COVID-19. The design of vitamin D randomised controlled trials is notoriously problematic and these trials commonly fail for a number of behavioural and methodological reasons. In Ireland, as in most other countries, low vitamin D status is common in older adults, adults in institutions, and with obesity, dark skin, low UVB exposure, diabetes and low socio-economic status. Physiological vitamin D levels for optimal immune function are considerably higher than those that can be achieved from food and sunlight exposure alone in Ireland. A window exists in which a significant number of adults could benefit from vitamin D supplementation, not least because of recent data demonstrating an association between vitamin D status and COVID-19. During the COVID pandemic, we believe that supplementation with 20-25ug (800-1000 IU)/day or more may be required for adults with apparently normal immune systems to improve immunity against SARS-CoV-2. We expect that higher monitored doses of 37.5-50 ug (1,500-2,000)/day may be needed for vulnerable groups (e.g., those with obesity, darker skin, diabetes mellitus and older adults). Such doses are within the safe daily intakes cited by international advisory agencies.

The Role of Comorbidities in Difficult-to-Control Asthma in Adults and Children

Assessment of asthma comorbidities, conditions that adversely affect the pathobiology of asthma or impair its response to therapies, is a fundamental step in the evaluation and management of patients with difficult-to-treat asthma. Identifying and effectively treating asthma comorbidities, such as obesity, obstructive sleep apnea, and chronic sinusitis with nasal polyps, may improve asthma control and reduce exacerbations. In addition, identifying comorbid T2 inflammatory conditions may help guide optimal selection of biologic therapies. Here, we describe common comorbid conditions found in adult and pediatric difficult-to-control asthma, discuss evidence for the association with asthma morbidity and treatment benefit, and provide information on how and when to assess comorbidities.

Bibliometric Analysis of Global Research Productivity on Vitamin D and Bone Metabolism (2001-2020): Learn from the Past to Plan Future

Vitamin D has long been known for preserving bone and non-skeletal health. Despite its magnitude of impact, scarce literature has explored the evolution of the relevant published literature. This study aimed at evaluating the trends and performance of Vitamin D and bone metabolism-related publications (2001−2020). All pertinent English language 16,887 articles were searched and extracted from the Web of Science (WoS) database and “R-Bibliometrix” was used for comprehensive analysis. Around 60,149 authors contributed from 114 countries, showing the USA on top with >1/4th of all articles, followed by Japan, China, and the United Kingdom. For authors, Cooper C, Dawson-Hughes B, and Holick MF were found to have written the most articles, citations and highest h-index, respectively. Corresponding authors from the top 20 countries collectively were responsible for around 84% of the articles. Among 2735 sources, Osteoporosis International (632), Journal of Bone and Mineral Research (569), and Bone (448) were foremost. Most prominent sources showed recent declining contributions. The increasing trend of publications with a higher spike from 2008 to 2014, followed by a gradual increase till 2017, was observed. Leading countries, affiliations, and authors showed collaborative publications and were mostly from developed countries with limited contributions, particularly from low- and middle-income countries.

Can vitamin D3 supplementation reduce the time to severe asthma exacerbations in children with asthma?

Vitamin D deficiency in children needs to be treated irrespective of asthma benefits. The VDKA trial showed that vitamin D supplementation in school-age asthmatic children with vitamin D insufficiency did not improve asthma control. https://bit.ly/2UF3j61.

NHLBI ASTHMA NETWORKS: IMPROVING PATIENT CARE, MOVING TOWARD PERSONALIZED MEDICINE

The first NHLBI Clinical Trials Research Network was the Asthma Clinical Research Network (ACRN 1), which was born in 1993 to perform multiple controlled clinical trials for asthma: "… dispassionately examine new & existing therapies for asthma" and "… rapidly communicate findings to medical community," and therefore, to perform clinical trials drug companies could not or would not do. Among the many areas studied by the ACRN and its successor networks, through 2019, was how to effectively and safely use long-acting beta-agonists and to find novel alternatives for them. In its Tiotropium Add-On Trial (TALC) trial, the ACRN demonstrated that tiotropium as add on-therapy to inhaled corticosteroids (ICS) was effective and non-inferior to long-acting beta-agonist add on-therapy. During the lifetime of the clinical trial networks (1993-2020), 71 manuscripts including 25 major clinical trials were published, many which have laid the groundwork for precision approaches for asthma therapy and the now ongoing PrecISE Asthma Network.

Impact of rapid correction of vitamin D deficiency in asthmatic patients

BACKGROUND

Asthma is one of the most common chronic diseases, which is a growing public health concern worldwide. In recent years, there has been an increasing number of interests in the relationship between vitamin D level and asthma control. Hence, the objective of this study was to assess the effect of high doses of vitamin D₃ injection on asthmatic patient's respiratory condition and quality of life.

METHODS

This was a single arm, before and after interventional study involving 18 patients with moderate to severe asthma. Spirometry test, St George's respiratory questionnaire (SGRQ) and serum vitamin D assay were performed. Subjects with 25-hydroxyvitamin D₃ (25-(OH) D₃) < 20 ng/ml were deemed deficient (n = 18) and received 2 intramuscular injections of vitamin D₃ 300,000 IU at monthly intervals consecutively.

RESULTS

The mean changes of forced expiratory volume in the first second (FEV1) were significantly different in subjects who received vitamin D₃ injections (p = 0.008). Also, the mean changes in FEV1/forced vital capacity ratio (FEV1/FVC) were significant (p < 0.001) as well as maximum expiratory flow between 25% and 75% of FVC (MEF25-75) (p = 0.001). Interestingly, improvement in clinical parameters of SGRQ was also observed with significant differences in total score (p = 0.001). Naturally, serum vitamin D levels were increased in our patients following the injections (p < 0.001).

CONCLUSIONS

Our findings suggest that screening for serum 25-(OH) D₃ deficiency is important in asthmatic patients and correction of this deficiency with high doses of vitamin D₃ injection may lead to improvement in pulmonary function, symptoms and quality of life (QOL).

Vitamin D recommendations in clinical guidelines: A systematic review, quality evaluation and analysis of potential predictors

BACKGROUND

Vitamin D has been widely promoted for bone health through supplementation and fortification of the general adult population. However, there is growing evidence that does not support these strategies. Our aim is to review the quality and recommendations on vitamin D nutritional and clinical practice guidelines and to explore predictive factors for their direction and strength.

METHODS

We searched three databases and two guideline repositories from 2010 onwards. We performed a descriptive analysis, a quality appraisal using AGREE II scores (Appraisal of Guidelines Research and Evaluation) and a bivariate analysis evaluating the association between direction and strength of recommendations, AGREE II domains' scores and pre-specified characteristics.

RESULTS

We included 34 guidelines, 44.1% recommended, 26.5% suggested and 29.4% did not recommend vitamin D supplementation. Guidelines that scored higher for "editorial independence" and "overall quality score" were less likely to recommend or suggest vitamin D supplementation (median 68.8 vs 35.4; P = .001 and 58.3 vs 37.5; P = .02). Guidance produced by government organisations and those that reported source of funding were associated with higher AGREE II scores. Unclear role of source of funding was associated with recommending or suggesting vitamin D supplementation (P = .034). Editorial independence was an independent predictor for recommending or suggesting vitamin D supplementation (OR 1.09; CI95% 1.02 to 1.16; P = .006).

CONCLUSIONS

Policymakers, clinicians and patients should be aware that lower quality guidelines and those reporting conflicts of interest are more likely to promote vitamin D supplementation. Guideline organisations should improve the quality of their recommendations' development and the management of conflicts of interest. Users and editors should be aware of these findings when using and appraising guidelines.

Lipid Nutrition in Asthma

Asthma is a heterogeneous pulmonary disease that has constantly increased in prevalence over the past several decades. Primary symptoms include airway constriction, airway hyperresponsiveness, and airway remodeling with additional symptoms such as shortness of breath, wheezing, and difficulty breathing. Allergic asthma involves chronic inflammation of the lungs, and the rise in its yearly diagnosis is potentially associated with the increased global consumption of foods similar to the western diet. Thus, there is growing interest into the link between diet and asthma symptoms, with mounting evidence for an important modulatory role for dietary lipids. Lipids can act as biological mediators in both a proinflammatory and proresolution capacity. Fatty acids play key roles in signaling and in the production of mediators in the allergic and inflammatory pathways. The western diet leads to a disproportionate ω-6:ω-3 ratio, with drastically increased ω-6 levels. To counteract this, consumption of fish and fish oil and the use of dietary oils with anti-inflammatory properties such as olive and sesame oil can increase ω-3 and decrease ω-6 levels. Increasing vitamin intake, lowering LDL cholesterol levels, and limiting consumption of oxidized lipids can help reduce the risk of asthma and the exacerbation of asthmatic symptoms. These dietary changes can be achieved by increasing intake of fruits, vegetables, nuts, oily fish, seeds, animal-related foods (eggs, liver), cheeses, grains, oats, and seeds, and decreasing consumption of fried foods (especially fried in reused oils), fast foods, and heavily processed foods.

Vitamin D can safely reduce asthma exacerbations among corticosteroid-using children and adults with asthma: a systematic review and meta-analysis of randomized controlled trials

Previous studies have failed to draw a consistent conclusion over the effect of vitamin D administration on asthma. We hypothesized that vitamin D supplementation could improve the clinical efficacy of corticosteroids in patients with asthma as measured by exacerbations, Asthma Control Test (ACT) score, and lung function in order to maintain asthma control. We searched Web of Science, PubMed, the Cochrane Library, and ScienceDirect up through January 20, 2021 for randomized controlled trials analyzing the effect of vitamin D supplementation on asthma exacerbation. Studies were limited to patients with moderate to severe asthma who were treated with corticosteroids. We identified 12 studies involving 1,543 participants in this meta-analysis. Vitamin D supplementation significantly reduced the risk of asthma exacerbation (pooled risk ratio (RR) 0.70, 95% confidence interval (CI), 0.59, 0.83; P < .05). The pooled RR of the ACT score was 0.04 (95% CI, -0.19, 0.27; P > .05). The pooled standardized mean difference in vitamin D levels was 1.07 (95% CI, 0.77, 1.38; P < .05), and in the percentage of forced expiratory volume in one second was -0.02 (95% CI, -0.13, 0.09; P > .05). The pooled RR of adverse events was 1.06 (95% CI, 0.89, 1.25; P > .05). We performed subgroup analysis and meta-regression of serum vitamin D levels but found no source of heterogeneity. Vitamin D supplementation safely reduced the rate of asthma exacerbation but did not improve ACT score or lung function among patients with asthma treated with corticosteroids.

Influence of vitamin D supplementation on the quality of life of asthma patients: Findings from ACVID randomised clinical trial

Published data on vitamin D and the quality of life of asthma patients are scarce and disparate. The ACVID clinical trial, published in 2020, showed the efficacy of calcifediol in improving asthma control in asthma patients with vitamin D deficiency. Data on vitamin D and quality of life measured by the Mini-AQLQ questionnaire were analysed: supplemented patients showed improved quality of life compared with a placebo group, and the initial mini-AQLQ scores were improved for both groups.

Oral and Topical Vitamin D, Sunshine, and UVB Phototherapy Safely Control Psoriasis in Patients with Normal Pretreatment Serum 25-Hydroxyvitamin D Concentrations: A Literature Review and Discussion of Health Implications

Vitamin D, sunshine and UVB phototherapy were first reported in the early 1900s to control psoriasis, cure rickets and cure tuberculosis (TB). Vitamin D also controlled asthma and rheumatoid arthritis with intakes ranging from 60,000 to 600,000 International Units (IU)/day. In the 1980s, interest in treating psoriasis with vitamin D rekindled. Since 1985 four different oral forms of vitamin D (D2, D3, 1-hydroxyvitaminD3 (1(OH)D3) and 1,25-dihydroxyvitaminD3 (calcitriol)) and several topical formulations have been reported safe and effective treatments for psoriasis-as has UVB phototherapy and sunshine. In this review we show that many pre-treatment serum 25(OH)D concentrations fall within the current range of normal, while many post-treatment concentrations fall outside the upper limit of this normal (100 ng/mL). Yet, psoriasis patients showed significant clinical improvement without complications using these treatments. Current estimates of vitamin D sufficiency appear to underestimate serum 25(OH)D concentrations required for optimal health in psoriasis patients, while concentrations associated with adverse events appear to be much higher than current estimates of safe serum 25(OH)D concentrations. Based on these observations, the therapeutic index for vitamin D needs to be reexamined in the treatment of psoriasis and other diseases strongly linked to vitamin D deficiency, including COVID-19 infections, which may also improve safely with sufficient vitamin D intake or UVB exposure.

Efficacy of vitamin D supplementation in asthmatic children with vitamin D deficiency: A randomized controlled trial (ESDAC trial)

BACKGROUND

Vitamin D supplementations for asthma control had shown inconsistent results. We aimed to study efficacy and safety of vitamin D supplementation in asthmatic children who were vitamin D deficient.

METHODS

This double-blind, randomized controlled trial enrolled asthmatic children of 4-12 years of age who had 25-hydroxyvitamin D [25(OH)D] levels <20 ng/mL. The participants were randomized to receive either vitamin D orally 1000 IU/d for 9 months or similar-looking placebo. The primary outcomes were the proportion of children having the Childhood Asthma Control Test (CACT) score of ≥20 at the end of the treatment and adverse effects.

RESULTS

The trial included 250 children (125 in each group) with a mean age of 8.1 ± 2.3 years and 180 boys. The baseline parameters were similar between the groups, including CACT score (21.7 ± 4.2 vs 21.9 ± 3.6, vitamin D vs placebo). At the end of the study, the proportion of asthmatic children who had CACT score ≥ 20 was similar between vitamin D and placebo group (93.6% vs 92.0%, P = .625). The number of exacerbations of asthma and side effect profile was also identical between the groups. 25(OH)D levels increased significantly in the vitamin D group (18.06 ± 7.11 vs 12.03 ± 5.98 ng/mL, P < .001). The results did not change when we did subgroup analysis for children with baseline CACT score < 20 and 25(OH)D levels at the end of the study ≥20 ng/mL.

CONCLUSION

Vitamin D supplementation in asthmatic children with vitamin D deficiency did not improve control of asthma.

Oxidative stress and obesity-related asthma

Obesity is an asthma comorbidity associated with poor control, increased exacerbation risk and reduced response to inhaled and systemic corticosteroids. It affects children and adults differentially. In those with early onset asthma, it associated with increased eosinophilic inflammation, whereas in late onset, it correlates with lower nitric oxide (NO) and predominantly non-T2 inflammation. There are probably multiple pathways by which obesity impacts asthma; airway and systemic oxidative stress has been proposed as a mechanism that could potentially explain the obesity mediated increased comorbidity and poor response to treatment. More likely than not, oxidative stress is an epiphenomenon of a very diverse set of processes driven by complex changes in airway and systemic metabolism. This article provides a comprehensive overview of the clinical, metabolic, pathophysiological and therapeutic aspects of oxidative stress in patients with obesity and asthma.

Vitamin D supplements: The pharmacists' perspective

OBJECTIVE

The purpose of this narrative review was to provide guidance for pharmacists concerning vitamin D supplementation.

METHODS

Relevant studies were identified in a search of MEDLINE/PubMed, EBSCOhost, and Google Scholar from January 1966 to September 2020 using the search terms vitamin D, vitamin D₂, vitamin D₃, calcitriol, and vitamin D deficiency. Abstracts were reviewed for relevance and, if relevant, full-text articles were retrieved and reviewed. References were checked, and citation searches using identified studies were conducted. The literature search included English-language studies involving administration of vitamin D monotherapy compared with placebo.

RESULTS

Serum 25-hydroxyvitamin D levels of less than 12 ng/mL indicate a vitamin D deficiency. The Institute of Medicine recommends a daily intake of 600 IU of vitamin D in individuals aged up to 70 years and 800 IU in those aged above 70 years. Vitamin D is labeled for rickets, osetomalacia, hypophosphatemia (familial or secondary), renal osteodystrophy, and corticosteroid-induced osteoporosis. When used for these indications, vitamin D should be prescribed with appropriate monitoring by a qualified health care practitioner. There is evidence for vitamin D supplementation in individuals aged 75 years or older and in those with problems associated with mobility, gait, or balance. There is insufficient evidence to support vitamin D supplementation in the prevention of cardiovascular disease, cancer, asthma, chronic obstructive pulmonary disease exacerbations, new-onset type 2 diabetes, infectious lung diseases, cognitive dysfunction, Alzheimer disease, and depression, or in prenatal use.

CONCLUSION

Pharmacists can provide evidence-based recommendations concerning the indications, dosing, monitoring, and adverse effects of vitamin D supplements.

Obesity-related asthma in children: A role for vitamin D

Excess adipose tissue predisposes to an enhanced inflammatory state and can contribute to the pathogenesis and severity of asthma. Vitamin D has anti-inflammatory properties and low-serum levels are seen in children with asthma and in children with obesity. Here we review the intersection of asthma, obesity, and hypovitaminosis D in children. Supplementation with vitamin D has been proposed as a simple, safe, and inexpensive adjunctive therapy in a number of disease states. However, little research has examined the pharmacokinetics of vitamin D and its therapeutic potential in children who suffer from obesity-related asthma.

Clinical correlates of rhinovirus infection in preschool asthma

Background

Investigation of preschool asthma is important since not all children outgrow their illness during this age. Data are scarce on the role of rhinovirus (RV) infections in this patient group.

Objectives

To investigate the role of RV infections in preschool asthma: (i) susceptibility factors, (ii) clinical course, and (iii) medium‐term outcome.

Methods

A total of 130 asthmatic children aged 4‐6 years from the multinational PreDicta cohort were prospectively followed for a 12‐month period. Allergy tests and a standard health questionnaire were carried out at study entry. Respiratory virus presence in nasopharyngeal washes was studied at illness visits and at 3 scheduled visits.

Results

At study entry, mean age of the children was 5.3 years. Of 571 visits, 54% were positive for any virus and 39% for RV. Patient characteristics were only assessed with RV infection due to low number of other viruses. The use of supplementary vitamin D was inversely associated with RV infection (P < .05). RV infection was associated with more severe course of acute illness in terms of more severe nighttime coughing, more sleep disturbances, and more days with runny nose (all P < .05). RV infection was also associated with more severe disease course during the 12‐month follow‐up in terms of more nights with awakenings and more days of exercise‐related symptoms (both P < .05).

Conclusions

Vitamin D supplementation may have an anti‐rhinovirus effect. Both short‐ and medium‐term outcomes suggest RV infection to be an important clinical marker of instable preschool asthma.

Nutritional Interventions to Improve Asthma-Related Outcomes through Immunomodulation: A Systematic Review

Asthma is a chronic inflammatory disease of the airways, characterized by T-helper (Th) 2 inflammation. Current lifestyle recommendations for asthma patients are to consume a diet high in fruits and vegetables and to maintain a healthy weight. This raises the question of whether other nutritional interventions may also improve asthma-related outcomes and whether these changes occur via immunomodulation. Therefore, we systematically reviewed studies that reported both asthma-related outcomes as well as immunological parameters and searched for relations between these two domains. A systematic search identified 808 studies, of which 28 studies met the inclusion criteria. These studies were divided over six nutritional clusters: herbs, herbal mixtures and extracts (N = 6); supplements (N = 4); weight loss (N = 3); vitamin D3 (N = 5); omega-3 long-chain polyunsaturated fatty acids (LCPUFAs) (N = 5); and whole-food approaches (N = 5). Fifteen studies reported improvements in either asthma-related outcomes or immunological parameters, of which eight studies reported simultaneous improvements in both domains. Two studies reported worsening in either asthma-related outcomes or immunological parameters, of which one study reported a worsening in both domains. Promising interventions used herbs, herbal mixtures or extracts, and omega-3 LCPUFAs, although limited interventions resulted in clinically relevant results. Future studies should focus on further optimizing the beneficial effects of nutritional interventions in asthma patients, e.g., by considering the phenotypes and endotypes of asthma.

Cytokine levels in children and adults with wheezing and asthma show specific patterns of variability over time

Levels of cytokines are used for in-depth characterization of patients with asthma; however, the variability over time might be a critical confounder. To analyze the course of serum cytokines in children, adolescents and adults with asthma and in healthy controls and to propose statistical methods to control for seasonal effects. Of 532 screened subjects, 514 (91·5%) were included in the All Age Asthma Cohort (ALLIANCE). The cohort included 279 children with either recurrent wheezing bronchitis (more than two episodes) or doctor-diagnosed asthma, 75 healthy controls, 150 adult asthmatics and 31 adult healthy controls. Blood samples were collected and 25 μl serum was used for analysis with the Bio-Plex Pr human cytokine 27-Plex assay. Mean age, body mass index and gender in the three groups of wheezers, asthmatic children and adult asthmatics were comparable to healthy controls. Wheezers (34·5%), asthmatic children (78·7%) and adult asthmatics (62·8%) were significantly more often sensitized compared to controls (4·5, 22 and 22·6%, respectively). Considering the entire cohort, interleukin (IL)-1ra, IL-4, IL-9, IL-17, macrophage inflammatory protein (MIP)-1- α and tumor necrosis factor (TNF)- α showed seasonal variability, whereas IL-1β, IL-7, IL-8, IL-13, eotaxin, granulocyte colony-stimulating factor (G-CSF), interferon gamma-induced protein (IP)-10, MIP-1 β and platelet-derived growth factor (PDGF)-BB did not. Significant differences between wheezers/asthmatics and healthy controls were observed for IL-17 and PDGF-BB, which remained stable after adjustment for the seasonality of IL-17. Seasonality has a significant impact on serum cytokine levels in patients with asthma. Because endotyping has achieved clinical importance to guide individualized patient-tailored therapy, it is important to account for seasonal effects.

Airway Redox Homeostasis and Inflammation Gone Awry: From Molecular Pathogenesis to Emerging Therapeutics in Respiratory Pathology

As aerobic organisms, we are continuously and throughout our lifetime subjected to an oxidizing atmosphere and, most often, to environmental threats. The lung is the internal organ most highly exposed to this milieu. Therefore, it has evolved to confront both oxidative stress induced by reactive oxygen species (ROS) and a variety of pollutants, pathogens, and allergens that promote inflammation and can harm the airways to different degrees. Indeed, an excess of ROS, generated intrinsically or from external sources, can imprint direct damage to key structural cell components (nucleic acids, sugars, lipids, and proteins) and indirectly perturb ROS-mediated signaling in lung epithelia, impairing its homeostasis. These early events complemented with efficient recognition of pathogen- or damage-associated recognition patterns by the airway resident cells alert the immune system, which mounts an inflammatory response to remove the hazards, including collateral dead cells and cellular debris, in an attempt to return to homeostatic conditions. Thus, any major or chronic dysregulation of the redox balance, the air-liquid interface, or defects in epithelial proteins impairing mucociliary clearance or other defense systems may lead to airway damage. Here, we review our understanding of the key role of oxidative stress and inflammation in respiratory pathology, and extensively report current and future trends in antioxidant and anti-inflammatory treatments focusing on the following major acute and chronic lung diseases: acute lung injury/respiratory distress syndrome, asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, and cystic fibrosis.

Vitamin D Supplementation As a Potential therapeutic Mediator in Asthma: Does Dose Really Matter? a Critical Review of the Literature

Around 400 million people across the globe will suffer from asthma in the next 10 years. Although most asthmatics use asthma medications regularly, they occasionally visit the emergency department for aggressive treatment amidst family anxiousness. Vitamin D (VD) not only regulates the expression of genes associated with calcium homeostasis, but also the genes associated with cancers, autoimmune diseases, and infection. VD has also non-genomic activities e.g. it is a potentially safe and effective novel strategy for decreasing the asthma episodes and controlling exacerbations. Our review assessed the dose, serum level, duration of administration and outcomes of VD in cases of asthmas. Although a body of research evidences the effectiveness of VD supplementation in asthma, other studies showed the insignificant response of VD to asthma either with low dose or low achieved serum VD levels. Nevertheless, recent reviews suggest that manipulating VD status holds promise for primary prevention and treatment of asthma. Future research on the relationship between VD and asthma should consider utilizing adequate doses of VD preparations for sufficient duration (likely to be >12 months) aiming to achieve appropriate level of serum VD (25-hydroxyvitamin D) concentration (likely to be at least >40 ng/mL).

A High-Content Screen for Mucin-1-Reducing Compounds Identifies Fostamatinib as a Candidate for Rapid Repurposing for Acute Lung Injury

Drug repurposing has the advantage of identifying potential treatments on a shortened timescale. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high-content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce mucin-1 (MUC1) protein abundance. Elevated MUC1 levels predict the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and correlate with poor clinical outcomes. Our screen identifies fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo, fostamatinib reduces MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro, SYK inhibition by the active metabolite R406 promotes MUC1 removal from the cell surface. Our work suggests fostamatinib as a repurposing drug candidate for ALI.