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

High ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 increases the risk of asthma attack in American asthma adults: a population study

OBJECTIVE

The relationship between vitamin D3 and asthma remains controversial. However, previous studies have largely overlooked the impact of epi-25-(OH)-vitamin D3. This study aims to investigate the effects of different forms of vitamin D3 on asthma attack in adults.

METHODS

In this cross-sectional study, a total of 3,873 eligible adult participants were extracted from the national health and nutrition examination survey (NHANES) database from 2007 to 2018. Based on quartiles method, different levels of vitamin D were divided into four groups (Quartile 1-4). Bivariate correlation analysis was performed for vitamin D and covariates to avoid multicollinearity. Multivariate logistic regression was used to investigate the association between serum levels of vitamin D3 (epi-25-(OH)-vitamin D3 and 25-(OH)-vitamin D3) and asthma attack, adjusting for covariates including age, gender, race, length of time in the U.S., house poverty income ratio (PIR), education level, smoking history, hypertension history, and diabetes history. The ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 was used for secondary analysis of its association with asthma attack. The outcomes were assessed by odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among the 3,873 eligible adults American with asthma, 1,508 (38.94%) had experienced at least one acute asthma attack in the past year. There was no significant correlation between vitamin D and covariates. After adjusting for covariates including age, gender, race, length of time in the U.S., house poverty income ratio (PIR), education level, smoking history, hypertension history and diabetes history, we found a positive correlation between the ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 and asthma attack. Additionally, a high ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 was more common among elder, male, of normal weight, non-Hispanic American, have a long time stay in the U.S., a high house PIR, and a history of hypertension individuals.

CONCLUSION

Our findings suggest that attention should be given to asthma attack associated with a high ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 in American adults who are elderly, male, of normal weight, non-Hispanic Americans, have long-term residence in the U.S., a high house PIR, and a history of hypertension.

The role of IL-2 cytokine family in asthma

BACKGROUND

The interleukin-2 (IL-2) family of cytokines, including IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21, are pivotal regulators of the immune response, impacting both innate and adaptive immunity. Understanding their molecular characteristics, receptor interactions, and signalling pathways is essential for elucidating their roles in health and disease.

OBJECTIVES

This review provides a comprehensive overview of the IL-2 family of cytokines, highlighting their molecular biology, receptor interactions, and signalling mechanisms. Furthermore, it explores the involvement of IL-2 family cytokines in the pathogenesis of chronic respiratory diseases, with a specific focus on chronic obstructive pulmonary disease (COPD) and asthma.

METHODS

A thorough literature review was conducted to gather insights into the molecular biology, receptor interactions, and signalling pathways of IL-2 family cytokines. Additionally, studies investigating the roles of these cytokines in chronic respiratory diseases, particularly COPD and asthma, were analysed to discern their implications in wider pathophysiology of disease.

RESULTS

IL-2 family cytokines exert pleiotropic effects on immune cells, modulating cellular proliferation, differentiation, and survival. Dysregulation of IL-2 family cytokines has been implicated in the pathogenesis of chronic respiratory illnesses, including COPD and asthma. Elevated levels of IL-2 and IL-9 have been associated with disease severity in COPD, while IL-4 and IL-9 play crucial roles in asthma pathogenesis by promoting airway inflammation and remodelling.

CONCLUSION

Understanding the intricate roles of IL-2 family cytokines in chronic respiratory diseases provides valuable insights into potential therapeutic targets for these conditions. Targeting specific cytokines or their receptors may offer novel treatment modalities to attenuate disease progression and improve clinical outcomes in patients with COPD and asthma.

Association between dietary carotenoid intakes and the risk of asthma in children and adolescents: evidence from the National Health and Nutrition Examination Survey 2007-2016

Background

In recent years, the incidence of asthma in children has been increasing. As a chronic disease, in addition to drug treatment, dietary management is also important. However, studies of carotenoids and asthma have shown mixed results. This study aimed to evaluate whether the relationship between carotenoid intake and current asthma holds significant importance.

Methods

We studied 9,118 children aged 6-16 years in the National Health and Nutrition Examination Survey (NHANES) of US from 2007 to 2016, and the relationship of dietary carotenoid and its subgroup with pediatric asthma. Current asthma was assessed by parent-reported, doctor-diagnosed, asthma using a standardized questionnaire. We used multivariate logistic regression to calculate the odds ratio (OR) for current asthma with a 95% confidence interval (CI).

Results

Total carotenoid intake was not associated with the risk of current asthma. Compared with the first quantile, the second quantile of β-cryptoxanthin intake was positively correlated with current asthma (Q2: 1.227; 95% CI: 1.025-1.470; P=0.03). The test of trend showed that, as the α-carotene intake increased, the risk of current asthma showed a decreasing trend, which was very close to the statistic confidence cutoff (Model I: P for trend =0.001; Model II: P for trend =0.003; Model III: P for trend =0.08). In subgroup analysis, family history of asthma interacted with carotenoid intake (P=0.005). The population without a family history of asthma, there were significant negative associations between carotenoid intakes and asthma (quartile 4: Model III: 0.720; 95% CI: 0.549-0.943; P=0.02).

Conclusions

In this study, pediatric current asthma was not related to total carotenoids in our total participants. Total dietary carotenoid intake has a protective effect on children without a family history of asthma. Meanwhile, β-cryptoxanthin intake is positively correlated with asthma.

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.

[Therapeutic effect of vitamin D supplementation in mexican patients with allergic rhinitis]

OBJETIVES

To evaluate the impact of cholecalciferol (D₃) supplementation using clinical and paraclinical variables in patients with RA and vitamin D insufficiency and deficiency.

METHODS

A randomized, double-blind, placebo-controlled study included patients from 5 to 40 years with a diagnosis of RA and vitamin D insufficiency and deficiency. They were supplemented for 8 weeks with 4000 or 5000 IU, depending on age. Total nasal symptoms score (TNSS) was measured monthly and 25(OH)D₃ levels at baseline and at the end of the study.

RESULTS

A total of 31 patients were included, with a mean age of 18.19 years. In the active group, there was a significant improvement in symptomatology with respect to the TNSS score and an increase in serum vitamin D levels (p < 0.01). There were no adverse reactions with cholecalciferol or placebo.

CONCLUSIONS

Supplementing patients with vitamin D₃, at the evaluated dose, together with conventional treatent for allergic rhinitis results in symptoms and quality of life improvement in patients with this disease.

Mini-Review on Vitamin D in Pediatric Population and its Role in Respiratory and Atopic Disorders

In recent years, our comprehension of the function of vitamin D has significantly evolved. The ubiquitous presence of the vitamin D receptor (Vitamin D Receptor- VDR) in the body has led to its redefinition from a steroidal hormone primarily involved in skeletal functions to a hormone with pleiotropic effects, exerting its influence on the circulatory, nervous, and immune systems. This has prompted investigations into its potential use in preventing and treating chronic metabolic disorders, cardiovascular diseases, infections, and allergic and autoimmune diseases. This comprehensive review explores the various aspects of vitamin D, including its sources, synthesis, functions, and its impact on different physiological systems. It delves into the epidemiology of vitamin D deficiency, highlighting its occurrence among various age demographics and geographic regions. The impact of vitamin D on the immune system is also explored, elucidating its immunomodulatory and anti-inflammatory properties, particularly in the context of respiratory infections. The review discusses emerging evidence concerning the potential advantages of vitamin D in respiratory diseases, pediatric asthma and atopic dermatitis. It also addresses vitamin D supplementation recommendations for various pediatric populations, including term and preterm infants. The growing concern regarding the global health impacts of insufficient vitamin D levels necessitates further research to bridge gaps in knowledge, particularly in enhancing screening, prevention, and approaches to address vitamin D deficiency from birth onwards. In summary, this comprehensive overview underscores the vital role of vitamin D, highlighting the significance of understanding its multifaceted functions and the need for tailored supplementation strategies, especially in vulnerable populations.

The incidence of asthma attributable to temperature variability: An ecological study based on 1990-2019 GBD data

BACKGROUND

Asthma, the second leading cause of death from chronic respiratory diseases, is associated with climate change, especially temperature changes. It is currently unclear about the relationship between long-term temperature variability and the incidence of asthma on a global scale.

METHODS

We used asthma incidence, demographic and socioeconomic data from the Global Burden of Disease (GBD) Results Database, and environmental and geographical statistics from TerraClimate between 1990 and 2019 to determine the association between maximum temperature variability and asthma incidence. We also predicted the incidence of heat-related asthma in the future (2020-2100) under four shared socioeconomic pathways (SSPs: 126, 245, 370, and 585).

RESULTS

Between 1990 and 2019, the global median incidence of asthma was 402.0 per 100,000 with a higher incidence (median: 1380.3 per 100,000) in children under 10 years old. We found that every 1 °C increase in maximum temperature variability increased the risk of asthma globally by 5.0 %, and the effect was robust for individuals living in high-latitude areas or aged from 50 to 70 years. By 2100, the average incidence of asthma is estimated to be reduced by 95.55 %, 79.32 %, and 40.02 % under the SSP126, SSP245, and SSP370 scenarios, respectively, compared to the SSP585 at latitudes >60°.

CONCLUSION

Our study provides evidence that maximum temperature variability is associated with asthma incidence. These findings suggest that implementing stricter mitigation and adaptation strategies may be importment in reducing asthma cases caused by climate change.

Breast feeding, obesity, and asthma association: clinical and molecular views

Asthma is a chronic condition that affects children worldwide. Accumulating number of studies reported that the prevalence of pediatric obesity and asthma might be altered through breastfeeding. It has been proposed that Leptin, which exists in human milk, is oppositely associated with weight increase in newborns. It may also influence peripheral immune system by promoting TH1 responses and suppressing TH2 cytokines. Leptin influences body weight and immune responses through complex signaling pathways at molecular level. Although previous studies provide explanations for the protective role of breastfeeding against both obesity and asthma, other factors such as duration of breastfeeding, parental, and prenatal factors may confound this relationship which requires further research.

Assessing the genetic relationship between gastroesophageal reflux disease and chronic respiratory diseases: a mendelian randomization study

BACKGROUND

Previous observational studies have found an association between gastroesophageal reflux disease (GERD) and chronic respiratory diseases, but it remains uncertain whether GERD causally influences these diseases. In this study, we aimed to estimate the causal associations between GERD and 5 chronic respiratory diseases.

METHODS

88 GERD-associated single nucleotide polymorphisms (SNPs) identified by the latest genome-wide association study were included as instrumental variables. Individual-level genetic summary data of participants were obtained from corresponding studies and the FinnGen consortium. We applied the inverse-variance weighted method to estimate the causality between genetically predicted GERD and 5 chronic respiratory diseases. Furthermore, the associations between GERD and common risk factors were investigated, and mediation analyses were conducted using multivariable MR. Various sensitivity analyses were also performed to verify the robustness of the findings.

RESULTS

Our study demonstrated that genetically predicted GERD was causally associated with an increased risk of asthma (OR 1.39, 95%CI 1.25-1.56, P < 0.001), idiopathic pulmonary fibrosis (IPF) (OR 1.43, 95%CI 1.05-1.95, P = 0.022), chronic obstructive disease (COPD) (OR 1.64, 95%CI 1.41-1.93, P < 0.001), chronic bronchitis (OR 1.77, 95%CI 1.15-2.74, P = 0.009), while no correlation was observed for bronchiectasis (OR 0.93, 95%CI 0.68-1.27, P = 0.645). Additionally, GERD was associated with 12 common risk factors for chronic respiratory diseases. Nevertheless, no significant mediators were discovered.

CONCLUSIONS

Our study suggested that GERD was a causal factor in the development of asthma, IPF, COPD and chronic bronchitis, indicating that GERD-associated micro-aspiration of gastric contents process might play a role in the development of pulmonary fibrosis in these diseases.

Assessing the Impact of Health Education Intervention on Asthma Knowledge, Attitudes, and Practices: A Cross-Sectional Study in Erbil, Iraq

Asthma causes chronic coughing, wheezing, dyspnea, and chest pressure. This study assessed asthmatic patients' knowledge, attitudes, and practice (KAP) of bronchial asthma and proper education on its meaning, risk factors, symptoms, diagnosis, management, and prevention practices. We performed a cross-sectional interventional asthma KAP survey in Erbil, Iraq. We adapted a validated study questionnaire from KAP studies in other nations to the Erbil situation and culture. In Erbil, Kurdistan, Iraq, two major hospitals' asthma clinics were studied. We chose 250 asthmatic patients from October 2018 to July 2019. Health education was comprehensive. The health education program used a Kurdish PowerPoint with a printout. Twenty-five groups received two weeks of one-hour health education pre-intervention. Each group was questioned before, 2 weeks after, and 12 weeks after health education. All data were analyzed by SPSS v26. The mean age of the respondents was 37.52 ± 15.16, with 48.7% of the respondents having a positive family history of asthma. After 2 weeks of health education intervention, respondents had a higher knowledge score and positive attitudes compared to pre-education, and after 12 weeks of education, there was a significant difference (p < 0.001) with improvised prevention practice. Health education programs led to considerable improvements in asthmatic patients' knowledge, attitudes, and practices regarding their condition. After receiving health education for a period of two weeks, the majority of the participants answered correctly regarding asthma, its causes, and the elements that trigger asthma attacks.

Risk of asthma in preterm infants with bronchopulmonary dysplasia: a systematic review and meta-analysis

BACKGROUND

This study aimed to systematically review and meta-analyze the available literature on the association between preterm infant bronchopulmonary dysplasia (BPD) and pre-adulthood asthma.

METHODS

Studies examining the association between BPD and asthma in children and adolescents were systematically reviewed, and a meta-analysis was conducted. We searched Scopus, Embase, Web of Science, PubMed, and Cochrane Library from the database inception to March 26, 2022. The pooled odds ratio (OR) estimate was used in our meta-analysis to calculate the correlation between BPD and the probability of developing asthma before adulthood. Stata 12.0 was used to conduct the statistical analysis.

RESULTS

The correlation between asthma and BPD in preterm newborns was examined in nine studies. We used a random effect model to pool the OR estimate. Our results indicated a marked increase in the risk of subsequent asthma in preterm infants with BPD [OR = 1.73, 95% confidence interval (CI) = 1.43-2.09]. Moreover, there was no obvious heterogeneity across the studies (P = 0.617, I2 = 0%). The pooled OR remained stable and ranged from 1.65 (95% CI = 1.35-2.01) to 1.78 (95% CI = 1.43-2.21). Regarding publication bias, the funnel plot for asthma risk did not reveal any noticeable asymmetry. We further performed Begg's and Egger's tests to quantitatively evaluate publication bias. There was no evidence of a publication bias for asthma risk (P > |Z| = 0.602 for Begg's test, and P > |t| = 0.991 for Egger's test).

CONCLUSIONS

Our findings indicate that preterm infants with BPD have a much higher risk of developing asthma in the future (OR = 1.73, 95% CI = 1.43-2.09). Preterm infants with BPD may benefit from long-term follow-up.

Progress in diagnosis and treatment of difficult-to-treat asthma in children

At present, medications containing inhaled corticosteroids (ICS-containing) are the keystones of asthma treatment. The majority of asthmatic children can significantly improve clinical outcomes with little worsening by standardized inhaled glucocorticoid treatment, but there is still a small proportion of children who are unable to achieve good symptom control even after the maximum standardized treatment, known as 'children with difficult-to-treat asthma (DA)'. The high heterogeneity of DA makes therapy challenging and expensive, which poses a serious risk to children's health and makes it extremely difficult for clinical physicians to accurately identify and treat children with DA. This article reviews the definition, evaluation, and treatment of this asthma in order to provide a reference for optimal clinical decision-making.

Vitamin D, exercise, and immune health in athletes: A narrative review

Vitamin D exerts important extra-skeletal effects, exhibiting an exquisite immune regulatory ability, affecting both innate and adaptive immune responses through the modulation of immunocyte function and signaling. Remarkably, the immune function of working skeletal muscle, which is fully recognized to behave as a secretory organ with immune capacity, is under the tight control of vitamin D as well. Vitamin D status, meaning hormone sufficiency or insufficiency, can push toward strengthening/stabilization or decline of immune surveillance, with important consequences for health. This aspect is particularly relevant when considering the athletic population: while exercising is, nowadays, the recommended approach to maintain health and counteract inflammatory processes, “too much” exercise, often experienced by athletes, can increase inflammation, decrease immune surveillance, and expose them to a higher risk of diseases. When overexercise intersects with hypovitaminosis D, the overall effects on the immune system might converge into immune depression and higher vulnerability to diseases. This paper aims to provide an overview of how vitamin D shapes human immune responses, acting on the immune system and skeletal muscle cells; some aspects of exercise-related immune modifications are addressed, focusing on athletes. The crossroad where vitamin D and exercise meet can profile whole-body immune response and health.