Linkage between smoking and asthma

Novel DNA methylation changes in mouse lungs associated with chronic smoking

Smoking is a potent cause of asthma exacerbations, chronic obstructive pulmonary disease (COPD) and many other health defects, and changes in DNA methylation (DNAm) have been identified as a potential link between smoking and these health outcomes. However, most studies of smoking and DNAm have been done using blood and other easily accessible tissues in humans, while evidence from more directly affected tissues such as the lungs is lacking. Here, we identified DNAm patterns in the lungs that are altered by smoking. We used an established mouse model to measure the effects of chronic smoke exposure first on lung phenotype immediately after smoking and then after a period of smoking cessation. Next, we determined whether our mouse model recapitulates previous DNAm patterns observed in smoking humans, specifically measuring DNAm at a candidate gene responsive to cigarette smoke, Cyp1a1. Finally, we carried out epigenome-wide DNAm analyses using the newly released Illumina mouse methylation microarrays. Our results recapitulate some of the phenotypes and DNAm patterns observed in human studies but reveal 32 differentially methylated genes specific to the lungs which have not been previously associated with smoking. The affected genes are associated with nicotine dependency, tumorigenesis and metastasis, immune cell dysfunction, lung function decline, and COPD. This research emphasizes the need to study CS-mediated DNAm signatures in directly affected tissues like the lungs, to fully understand mechanisms underlying CS-mediated health outcomes.

Association of life's essential 8 and asthma: mediating effect of inflammation and oxidative stress

BACKGROUND

The association of cardiovascular health (CVH) with asthma risk in U.S. adults remains unclear. This study aimed to explore the association of Life's Essential 8 (LE8), a measurement of CVH, with asthma and investigate the potential mediating effect of inflammation and oxidative stress.

METHODS

The data was obtained from the National Health and Nutrition Examination Survey (NHANES) in 2005-2018. LE8 score (range 0 ∼ 100) was measured and categorized as low (<50), moderate (50 ∼ <80), and high (≥80) CVH. Survey-weighted logistic regression and restricted cubic spline model were employed to explore the association between LE8 score and asthma. Mediation analyses were conducted to identify the mediating effects of inflammation and oxidative stress biomarkers.

RESULTS

This study included 10,932 participants aged ≥ 20 years, among whom 890 (8.14%) reported prevalent asthma. After adjusting for all covariates, the odd ratios (OR) for asthma were 0.67 (95% confidence interval (CI): 0.48, 0.94) in the moderate CVH group and 0.52 (95% CI: 0.34, 0.79) in the high CVH group compared with the low CVH group, respectively. The OR for asthma was 0.85 (95% CI: 0.78, 0.93) for every 10 score increase in LE8 score, and linear dose-response relationship was observed (p = 0.0642). Mediation analyses showed that inflammation and oxidative stress mediated 15.97% and 11.50% of the association between LE8 score and asthma, respectively (all p < 0.05).

CONCLUSIONS

LE8 score was negatively associated with asthma, and inflammation and oxidative stress partially mediated this association. It is recommended that maintaining optimal CVH may prevent asthma.

Disease burden and risk factors of children aged 0-14 years in China: a retrospective study on data from the Global Burden of Disease Study 2019

OBJECTIVES

This study aimed to analyse the current status, trends and risk factors of disease burden from 1990 to 2019 among Chinese children.

DESIGN AND PARTICIPANTS

It was a retrospective study on data from the Global Burden of Disease Study 2019 (GBD 2019). Data of disease burden and risk factors were extracted from the GBD 2019. Children were divided into two groups of <5 and 5-14 years. Data were analysed using GBD results query tool, Excel and Pareto analysis.

PRIMARY OUTCOME MEASURES

Disability-Adjusted Life Years (DALYs) and deaths.

RESULTS

The overall disease burden for both children <5 years and those aged 5-14 years significantly decreased from 1990 to 2019. For children aged <5 years, in 2019, the leading cause of deaths and DALYs were 'neonatal disorders', and the top risk factor was 'low birth weight'. Compared with data of 1990, the ranking of causes of deaths and DALYs in 2019 saw the most significant increase for 'HIV/AIDS and sexually transmitted infections' and 'skin and subcutaneous diseases' respectively. Conversely, the ranking of deaths/DALYs causes that dropped most significantly was 'nutritional deficiencies'. For children aged 5-14, in 2019, the leading deaths and DALYs causes were 'unintentional injuries' and 'mental disorders' respectively. The top risk factors were 'alcohol use' and 'short gestation', respectively. The ranking of deaths and DALYs causes rose most significantly were 'HIV/AIDS and sexually transmitted infections' and 'neonatal disorders', respectively. Conversely, the ranking of deaths causes that dropped most significantly were 'other infectious diseases', 'enteric infections' and 'nutritional deficiencies'. For DALYs, the causes that dropped most significantly in ranking were 'other infectious diseases'.

CONCLUSIONS

The disease burden of children has significantly changed from 1990 to 2019, with notable differences between children aged <5 and 5-14 years. To optimise the allocation of health resources, it is necessary to adjust management strategies based on the latest disease burden.

The association between waist circumference and adult asthma attack using nationally representative samples

AIMS

This study aims to explore the relationship between waist circumference and asthma attack in adults.

METHODS

In this cross-sectional study, we analysed data from 5,530 U.S. adults diagnosed with asthma. Participants were categorized into two groups based on their experience of asthma attacks: with or without asthma attacks. We employed adjusted weighted logistic regression models, weighted restricted cubic splines, subgroup and sensitivity analyses to assess the association between waist circumference and asthma attack.

RESULTS

The median age of all participants was 43 years, and the median waist circumference was 98.9 cm, with a median BMI was 28.50 kg/m2. Participants in the asthma attack group had significantly higher waist circumferences than those in the non-attack group (P < 0.001). After full adjustment for body mass index-defined obesity, age, gender, race, education levels, poverty income ratio levels, smoking status, and metabolic syndrome, every 5 cm increase in waist circumference exhibited a 1.06 times higher likelihood of asthma attack probability. The weighted restricted cubic spline analysis demonstrated an increased risk of asthma attacks with rising waist circumference. Subgroup analyses confirmed this relationship across various groups differentiated by gender, age, and smoking status. When applying a stricter definition of asthma attack, the weighted logistic regression models showed robust association between waist circumference and asthma attack.

CONCLUSION

Waist circumference is an independent predictor of asthma attacks. Our findings underscore the importance of waist circumference measurement in evaluating the risk of asthma attacks.

The Effect of Minority Stress Processes on Smoking for Lesbian, Gay, Bisexual, Transgender, and Queer Individuals: A Systematic Review

Purpose: Lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals are more likely to smoke than non-LGBTQ individuals. Smoking has been posited as a coping mechanism for LGBTQ individuals facing minority stress. However, the exact relationship between minority stress and smoking behaviors among LGBTQ individuals is unclear. Therefore, the purpose of this systematic review was to examine how minority stress processes are associated with smoking behaviors for LGBTQ individuals. Methods: Searches of the PubMed and PsycINFO databases were conducted for smoking-, LGBTQ-, and minority stress-related terms. No date, geographic, or language limits were used. For inclusion, the study must have (1) been written in English, (2) had an LGBTQ group as the study population or a component of the study population, (3) assessed the cigarette smoking status of patients, and (4) assessed at least one minority stress-related process (internalized stigma, perceived stigma, or prejudice events). Results: The final review included 44 articles. Aside from two outlier studies, all of the reviewed studies exhibited that increased levels of minority stress processes (internalized queerphobia, perceived stigma, and prejudice events) were associated with increased probability of cigarette use in LGBTQ individuals. Increased minority stress was also associated with greater psychological distress/mental health decline. Conclusion: The findings of this review suggest that minority stress processes represent a contributing factor to smoking health disparities in LGBTQ populations. These results highlight the need for smoking cessation and prevention programs to address minority stress and improve smoking disparities in these populations.

Treatable Traits in Pregnant Women with Asthma

BACKGROUND

Asthma is the most common chronic respiratory disease in pregnancy, affecting approximately 8-10% of pregnant women. Uncontrolled asthma is associated with adverse perinatal outcomes, including low birth weight, preterm birth, and maternal complications such as pre-eclampsia.

SUMMARY

A current approach to the management of chronic airway diseases is based on targeting treatable traits. The aim of this review was to define treatable traits in pregnant women with asthma based on recent literature and to determine personalized treatment options according to these traits. Traits addressed in this review that may improve asthma control and pregnancy outcomes are fractional exhaled nitric oxide-based asthma monitoring and treatment, medication adherence and inhalation technique, impaired lung function, smoking cessation and comorbidity including psychological conditions (depression and anxiety), obesity, rhinitis, gastroesophageal reflux disease, chronic rhinosinusitis with or without nasal polyps, and sleep apnea.

KEY MESSAGES

All the treatable traits discussed have the potential to improve asthma control and pregnancy outcomes in pregnant women with asthma. Further research is needed to determine which management approaches are best to improve asthma control during pregnancy, to identify other relevant treatable traits, and to determine whether the treatable trait approach is feasible and beneficial in pregnant women with asthma.

Dysregulation of immunity by cigarette smoking promotes inflammation and cancer: A review

Smoking is a serious global health issue. Cigarette smoking contains over 7000 different chemicals. The main harmful components include nicotine, acrolein, aromatic hydrocarbons and heavy metals, which play the key role for cigarette-induced inflammation and carcinogenesis. Growing evidences show that cigarette smoking and its components exert a remarkable impact on regulation of immunity and dysregulated immunity promotes inflammation and cancer. Therefore, this comprehensive and up-to-date review covers four interrelated topics, including cigarette smoking, inflammation, cancer and immune system. The known harmful chemicals from cigarette smoking were summarized. Importantly, we discussed in depth the impact of cigarette smoking on the formation of inflammatory or tumor microenvironment, primarily by affecting immune effector cells, such as macrophages, neutrophils, and T lymphocytes. Furthermore, the main molecular mechanisms by which cigarette smoking induces inflammation and cancer, including changes in epigenetics, DNA damage and others were further summarized. This article will contribute to a better understanding of the impact of cigarette smoking on inducing inflammation and cancer.

Frequency and characteristics of asthma in smokers attending smoking cessation units in Spain

INTRODUCTION

The interaction between smoking and asthma impairs lung function and increases airflow obstruction severity. The identification of smoking patterns in smokers with and without asthma is crucial to provide the best care strategies. The aims of this study are to estimate asthma frequency, describe asthma features, and characterize smoking in smokers attending smoking cessation units.

MATERIAL AND METHODS

We carried out a cross-sectional study in five smoking cessation units with different geographical distribution to estimate asthma frequency in smokers, characterize asthma features in smokers, as well as smoking in asthmatic smokers.

RESULTS

Asthma frequency among smokers was 18.6%. Asthmatic smokers presented high passive exposure, low smoking self-efficacy and will to quit smoking, as well as a high exacerbation frequency, severe symptoms, and frequent use of long-acting beta agonists, inhaled steroids, and short-acting beta agonists.

DISCUSSION

Smokers with asthma constitute a high-risk group with worsened evolution of pulmonary involvement. All smokers should be regularly screened for asthma. Effective smoking cessation strategies should be proposed to smokers with asthma in order to reverse the harmful effects of smoking on the airway, together with a comprehensive and integral approach.

Molecular and functional changes in neutrophilic granulocytes induced by nicotine: a systematic review and critical evaluation

Background

Over 1.1 billion people smoke worldwide. The alkaloid nicotine is a prominent and addictive component of tobacco. In addition to tumors and cardiovascular disorders, tobacco consumption is associated with a variety of chronic-inflammatory diseases. Although neutrophilic granulocytes (neutrophils) play a role in the pathogenesis of many of these diseases, the impact of nicotine on neutrophils has not been systematically reviewed so far.

Objectives

The aim of this systematic review was to evaluate the direct influence of nicotine on human neutrophil functions, specifically on cell death/damage, apoptosis, chemotaxis, general motility, adhesion molecule expression, eicosanoid synthesis, cytokine/chemokine expression, formation of neutrophil extracellular traps (NETs), phagocytosis, generation of reactive oxygen species (ROS), net antimicrobial activity, and enzyme release.

Material and methods

This review was conducted according to the PRISMA guidelines. A literature search was performed in the databases NCBI Pubmed® and Web of Science™ in February 2023. Inclusion criteria comprised English written research articles, showing in vitro studies on the direct impact of nicotine on specified human neutrophil functions.

Results

Of the 532 originally identified articles, data from 34 articles were finally compiled after several evaluation steps. The considered studies highly varied in methodological aspects. While at high concentrations (>3 mmol/l) nicotine started to be cytotoxic to neutrophils, concentrations typically achieved in blood of smokers (in the nmol/l range) applied for long exposure times (24-72h) supported the survival of neutrophils. Smoking-relevant nicotine concentrations also increased the chemotaxis of neutrophils towards several chemoattractants, elevated their production of elastase, lipocalin-2, CXCL8, leukotriene B4 and prostaglandin E2, and reduced their integrin expression. Moreover, while nicotine impaired the neutrophil phagocytotic and anti-microbial activity, a range of studies demonstrated increased NET formation. However, conflicting effects were found on ROS generation, selectin expression and release of β-glucuronidase and myeloperoxidase.

Conclusion

Nicotine seems to support the presence in the tissue and the inflammatory and selected tissue-damaging activity of neutrophils and reduces their antimicrobial functions, suggesting a direct contribution of nicotine to the pathogenesis of chronic-inflammatory diseases via influencing the neutrophil biology.

Early life exposure to cigarette smoking and adult and old-age male mortality: Evidence from linked US full-count census and mortality data

BACKGROUND

Smoking is a leading cause of premature death across contemporary developed nations, but few longitudinal individual-level studies have examined the long-term health consequences of exposure to smoking.

OBJECTIVE

We examine the effect of fetal and infant exposure to exogenous variation in smoking, brought about by state-level cigarette taxation, on adulthood and old-age mortality (ages 55-73) among cohorts of boys born in the United States during the 1920s and 1930s.

METHODS

We use state-of-the-art methods of record linkage to match 1930 and 1940 US full-count census records to death records, identifying early life exposure to the implementation of state-level cigarette taxes through contemporary sources. We examine a population of 2.4 million boys, estimating age at death by means of OLS regression, with post-stratification weights to account for linking selectivity.

RESULTS

Fetal or infant exposure to the implementation of state cigarette taxation delayed mortality by about two months. Analyses further indicate heterogenous effects that are consistent with theoretical expectations; the largest benefits are enjoyed by individuals with parents who would have been affected most by the tax implementation.

CONCLUSIONS

Despite living in an era of continuously increasing cigarette consumption, cohorts exposed to a reduction in cigarette smoking during early life enjoyed a later age at death. While it is not possible to comprehensively assess the treatment effect on the treated, the magnitude of the effect should not be underestimated, as it is larger than the difference between having parents belonging to the highest and lowest socioeconomic groups.

CONTRIBUTION

The study provides the first estimates of long-run health effects from early life exposure to cigarette smoking.

Asthma and its relationship with anthropometric markers among adults

BACKGROUND

Many studies have examined the association between anthropometric indicators and the likelihood of developing asthma. However, no study has yet examined the link between asthma and anthropometric markers of risk. This study addresses this gap in the literature by evaluating the relationship between asthma, smoking, and anthropometric measurements such as body mass index (BMI), waist circumference (WC), hip circumference (HC), and waist-to-hip ratio (WHR) among individuals residing in the United States.

METHODS

This cross-sectional study conducted a secondary analysis of the 2011-2014 National Survey of Midlife Development in the United States, using data from 2,257 participants aged 25-74. We classified the participants into four groups based on self-reported smoking and asthma status: nonsmokers with no asthma, asthma alone, smokers only, and smokers with asthma. The outcomes of interest were BMI, WC, HC, and WHR scores in the latter three groups compared to the nonsmokers with no asthma group.

RESULTS

Linear regression analysis showed that those with asthma alone and smokers with asthma were significantly more likely to have a BMI, WC, or HC score of 1 or higher than people without asthma and smokers only.

CONCLUSION

A higher score on the anthropometric parameters was substantially related to participants who had only asthma and those who had both asthma and smoking.

Clinical Associations of Mucus Plugging in Moderate to Severe Asthma

BACKGROUND

Mucus plugging is recognized as a contributory factor to airway obstruction and symptoms in persistent asthma.

OBJECTIVE

We aimed to determine phenotypic associations of mucus plugging in patients with moderate to severe asthma in a real-life clinic setting.

METHODS

Mucus plugs (MPs) were identified by a thoracic radiologist upon high-resolution computed tomography imaging. A MP score was subsequently calculated and analyzed along with type 2 biomarkers, spirometry, severe exacerbations, and asthma control for 126 patients with moderate to severe asthma before biologic therapy.

RESULTS

Asthma patients with MP had significantly worse FEV₁%, forced expiratory flow at 25% to 75% of FVC percent, and FEV₁/FVC as well as higher levels of peripheral blood eosinophils, FeNO, total IgE, and Aspergillus fumigatus IgE titers, and had previously experienced more frequent severe exacerbations. FEV₁/FVC, more than two exacerbations per year, blood eosinophils, total IgE, and A fumigatus IgE titers were associated with MPs after adjusting for confounders.

CONCLUSIONS

Poorly controlled asthma patients with MPs exhibited significantly worse airflow obstruction and greater type 2 inflammation associated with more frequent severe exacerbations. Impaired spirometry, more frequent exacerbations, raised blood eosinophils, total IgE, and A fumigatus IgE increased the likelihood of MPs.

Relationships between antibiotic exposure and asthma in adults in the United States: results of the National Health and Nutrition Examination Survey between 1999 and 2018

Objectives

To investigate the relationship between antibiotic exposure and asthma in adults in the United States.

Methods

Data was obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2018. A total of 51,124 participants were included, excluding those who were aged < 20 years, female participants who were pregnant, and individuals who did not complete the prescription medications questionnaire and the medical conditions questionnaire regarding asthma status. Antibiotic exposure was defined as the utilization of antibiotics within the past 30 days, categorized based on the Multum Lexicon Plus therapeutic classification system. Asthma was defined as having a history of asthma or having an asthma attack or wheezing symptoms in the past year.

Results

The risk of asthma was found to be 2.557 (95% CI: 1.811, 3.612), 1.547 (95% CI: 1.190, 2.011) and 2.053 (95% CI: 1.344, 3.137) times greater in participants who had used macrolide derivatives, penicillin and quinolones in the past 30 days, respectively, compared with those not using antibiotics. After adjusting for demographic covariates and asthma-related factors, only macrolides derivatives were significantly associated with asthma in the 20-40 and 40-60 age groups. For individuals over 60 years old, quinolones were significantly associated with asthma. The effect of different types of antibiotic with asthma varied in male and female populations. Moreover, higher socioeconomic status, greater BMI, younger age, smoking habits, history of infection, chronic bronchitis, emphysema, and family history of asthma were all identified as risk factors for asthma.

Conclusion

Our study indicated that three types of antibiotics were significantly associated with asthma in different subgroups of the population. Therefore, the use of antibiotics should be more strictly regulated.

Human matters in asthma: Considering the microbiome in pulmonary health

Microbial communities form an important symbiotic ecosystem within humans and have direct effects on health and well-being. Numerous exogenous factors including airborne triggers, diet, and drugs impact these established, but fragile communities across the human lifespan. Crosstalk between the mucosal microbiota and the immune system as well as the gut-lung axis have direct correlations to immune bias that may promote chronic diseases like asthma. Asthma initiation and pathogenesis are multifaceted and complex with input from genetic, epigenetic, and environmental components. In this review, we summarize and discuss the role of the airway microbiome in asthma, and how the environment, diet and therapeutics impact this low biomass community of microorganisms. We also focus this review on the pediatric and Black populations as high-risk groups requiring special attention, emphasizing that the whole patient must be considered during treatment. Although new culture-independent techniques have been developed and are more accessible to researchers, the exact contribution the airway microbiome makes in asthma pathogenesis is not well understood. Understanding how the airway microbiome, as a living entity in the respiratory tract, participates in lung immunity during the development and progression of asthma may lead to critical new treatments for asthma, including population-targeted interventions, or even more effective administration of currently available therapeutics.

Association between constipation and the development of asthma: a meta-analysis

Background

Constipation has been hypothesized to be associated with the increased risk of wheezing or asthma. However, the relation remains a subject of debate. We conducted this meta-analysis to assess whether constipation influences the risk of wheezing/asthma.

Methods

PubMed, Embase, and Web of Science were systematically searched for studies published between 1955 and January 2022. Two reviewers independently extracted data and assessed the quality of each study. Results were pooled using fixed-effects models or random-effects models as appropriate.

Results

In total, 3 original articles with 178,661 participants, which met the criteria, were included in this meta-analysis. Constipation was associated with an increased risk of wheezing/asthma in later life (RR = 2.02, 95% CI = 1.24–3.29, P < 0.01).

Conclusions

The meta-analysis suggests an association between constipation and the subsequent development of wheezing/asthma. Well-designed and highly standardized prospective studies that adequately address concerns for potential confounding factors are required to validate the risk identified in our current meta-analysis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13223-022-00708-9.

Cigarette Smoke Particle-Induced Lung Injury and Iron Homeostasis

It is proposed that the mechanistic basis for non-neoplastic lung injury with cigarette smoking is a disruption of iron homeostasis in cells after exposure to cigarette smoke particle (CSP). Following the complexation and sequestration of intracellular iron by CSP, the host response (eg, inflammation, mucus production, and fibrosis) attempts to reverse a functional metal deficiency. Clinical manifestations of this response can present as respiratory bronchiolitis, desquamative interstitial pneumonitis, pulmonary Langerhans’ cell histiocytosis, asthma, pulmonary hypertension, chronic bronchitis, and pulmonary fibrosis. If the response is unsuccessful, the functional deficiency of iron progresses to irreversible cell death evident in emphysema and bronchiectasis. The subsequent clinical and pathological presentation is a continuum of lung injuries, which overlap and coexist with one another. Designating these non-neoplastic lung injuries after smoking as distinct disease processes fails to recognize shared relationships to each other and ultimately to CSP, as well as the common mechanistic pathway (ie, disruption of iron homeostasis).

Prevalence and early-life risk factors of school-age allergic multimorbidity: The EuroPrevall-iFAAM birth cohort

Background

Coexistence of childhood asthma, eczema and allergic rhinitis is higher than can be expected by chance, suggesting a common mechanism. Data on allergic multimorbidity from a pan‐European, population‐based birth cohort study have been lacking. This study compares the prevalence and early‐life risk factors of these diseases in European primary school children.

Methods

In the prospective multicentre observational EuroPrevall‐iFAAM birth cohort study, we used standardized questionnaires on sociodemographics, medical history, parental allergies and lifestyle, and environmental exposures at birth, 12 and 24 months. At primary school age, parents answered ISAAC‐based questions on current asthma, rhinitis and eczema. Allergic multimorbidity was defined as the coexistence of at least two of these.

Results

From 10,563 children recruited at birth in 8 study centres, we included data from 5,572 children (mean age 8.2 years; 51.8% boys). Prevalence estimates were as follows: asthma, 8.1%; allergic rhinitis, 13.3%; and eczema, 12.0%. Allergic multimorbidity was seen in 7.0% of the whole cohort, ranging from 1.2% (Athens, Greece) to 10.9% (Madrid, Spain). Risk factors for allergic multimorbidity, identified with AICc, included family‐allergy‐score, odds ratio (OR) 1.50 (95% CI 1.32–1.70) per standard deviation; early‐life allergy symptoms, OR 2.72 (2.34–3.16) for each symptom; and caesarean birth, OR 1.35 (1.04–1.76). Female gender, OR 0.72 (0.58–0.90); older siblings, OR 0.79 (0.63–0.99); and day care, OR 0.81 (0.63–1.06) were protective factors.

Conclusion

Allergic multimorbidity should be regarded as an important chronic childhood disease in Europe. Some of the associated early‐life factors are modifiable and may be considered for prevention strategies.

E-cigarette users are associated with asthma disease: A meta-analysis

BACKGROUND

At present, there are more than 300 million asthma patients in the world. Electronic cigarettes (e-cigarettes) are considered as a new way of smoking and are loved by young people. The relationship between e-cigarettes and asthma risk is still controversial. Therefore, we conducted a meta-analysis to explore the relationship between e-cigarettes and asthma.

METHODS

We searched PubMed, Embase, and Web of Science for research results published before august 2020. All data analysis was through R version 3.6.3. Publication bias was assessed using funnel plots, Begg's rank correlation test, and Egger regression asymmetry tests. Most of the included studies were adjusted for potential confounding factors.

RESULTS

This meta found the association of e-cigarette use with asthma, and the combined OR value was 1.27 (95% CI = 1.17-1.37). We found the significant association of current e-cigarette usage with asthma (OR = 1.30, 95% CI = 1.17-1.45), and the former use of e-cigarettes also had an association with asthma (OR = 1.22, 95% CI = 1.08-1.39). Then, when e-cigarettes were used in combination with traditional cigarettes, the association odds with asthma was 1.47 (95% CI = 1.13-1.91), which was higher than that of users who used traditional cigarettes (OR = 1.33, 95% CI = 1.19-1.49). In subgroup analysis, adult and female e-cigarette users were more closely associated with asthma.

CONCLUSION

In short, in this meta-analysis, we found that current or former use of e-cigarettes are associated with the prevalence of asthma. However, the specific relationship required more rigorous design for further verification.

Determination of Urinary Cotinine Cut-Off Concentrations for Pregnant Women in the Japan Environment and Children's Study (JECS)

Few studies have assessed the accuracy of self-reported questionnaires to determine smoking habits relative to urinary biomarkers. This study investigated urinary cotinine cut-off concentrations distinguishing active, passive and non-smokers among pregnant women who participated in the Japan Environment and Children's Study, a nationwide birth cohort study. Pregnant participants with measured urinary cotinine concentrations (UCCs) and who completed self-reported questionnaires on smoking status were included (n = 89,895). The cut-off values (COVs) for active and passive smokers were calculated by fitting mixed normal distribution functions to UCCs. The sensitivity and specificity of the questionnaires were subsequently evaluated. The median (interquartile range) UCC was 0.24 (0.083-0.96) µg/g-creatinine, with the detection rate of 89%. The COV for distinguishing active smokers from passive and non-smokers was 36.8 µg/g-creatinine. When this COV was considered to represent the true condition, the questionnaire had a sensitivity of 0.523, a specificity of 0.998, a positive predictive value (PPV) of 0.967 and a negative predictive value (NPV) of 0.957. The COV for distinguishing passive smokers from non-smokers was 0.31 µg/g-creatinine, with the questionnaire having a sensitivity of 0.222, a specificity of 0.977, a PPV of 0.868 and an NPV of 0.644. As many as 78% of passive smokers might be misclassified as non-smokers.

Japanese guidelines for childhood asthma 2020

The Japanese Guideline for Childhood Asthma (JGCA) 2020 is a translation of the Japanese Pediatric Guideline for the Treatment and Management of Asthma (JPGL) 2017 into English, which was published by the Japanese Society of Pediatric Allergy and Clinical Immunology. It makes recommendations for best practices in the management of childhood asthma, including management of acute exacerbations and non-pharmacological and pharmacological management. These guidelines will be of interest to non-specialist physicians involved in the care of children with asthma. In JPGL, JPGL2017 is the first evidence-based guidelines updated according to the GRADE system and Minds approach, and it addresses eight clinical questions about the treatment of childhood asthma. In children aged ≤5 years, infant and preschool asthma is diagnosed according to the response to short acting beta2 agonists or the effect of a therapeutic trial during 1 month with controller treatment and worsening after treatment cessation. Long-term management both promotes pharmacological therapy and measures against risk factors that induce exacerbation, better patient education and a partnership with trinity. In addition, long-term management should not be carried out without review but rather be based on a cycle of evaluation, adjustment and treatment. In JPGL2017, the transdermal patch and oral beta2 agonists are positioned as drugs within the concept of "short-term additional treatment" to be used until the symptoms are stabilized when the control state transiently deteriorates.

Gene-Environment Interaction between the IL1RN Variants and Childhood Environmental Tobacco Smoke Exposure in Asthma Risk

(1) Background: Variants of the interleukin-1 receptor antagonist (IL1RN) gene, encoding an anti-inflammatory cytokine, are associated with asthma. Asthma is a chronic inflammatory disease of the airway influenced by interactions between genetic variants and environmental factors. We discovered a gene-environment interaction (GEI) of IL1RN polymorphisms with childhood environmental tobacco smoke (ETS) exposure on asthma susceptibility in an urban adult population. (2) Methods: DNA samples from the NYU/Bellevue Asthma Registry were genotyped for tag SNPs in IL1RN in asthma cases and unrelated healthy controls. Logistic regressions were used to study the GEI between IL1RN variants and childhood ETS exposures on asthma and early onset asthma, respectively, adjusting for population admixture and other covariates. (3) Results: Whereas the rare genotypes of IL1RN SNPs (e.g., GG in SNP rs2234678) were associated with decreased risk for asthma among those without ETS exposure (odds ratio OR = 0.215, p = 0.021), they are associated with increased risk for early onset asthma among those with childhood ETS (OR = 4.467, p = 0.021). (4) Conclusions: We identified a GEI between polymorphisms of IL1RN and childhood ETS exposure in asthma. Analysis of GEI indicated that childhood ETS exposure disrupted the protective effect of some haplotypes/genotypes of IL1RN for asthma and turned them into high-risk polymorphisms for early onset asthma.

Airway inflammation and remodeling of cigarette smoking exposure ovalbumin-induced asthma is alleviated by CpG oligodeoxynucleotides via affecting dendritic cell-mediated Th17 polarization

Cigarette smoking (CS) is common in asthma, aggravating inflammatory reactions. However, the current treatment strategies for asthma are still not effective enough, and novel therapeutic approaches are required for CS-induced asthmatic disorders. We here investigated the ability of CpG oligodeoxynucleotides (CpG-ODNs) to inhibit airway inflammation and remodeling in ovalbumin (OVA)-associated asthma in mice exposed to chronic CS, revealing potential mechanistic insights. Lung tissue specimens were histologically analyzed. Th1/Th2/Th17 associated cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung specimens were quantitated by ELISA, qRT-PCR and immunoblot. Parameters of bone marrow-derived dendritic cells (BMDCs) functions were evaluated as well. The results showed that BALB/c mice after CS and OVA treatments developed an asthmatic phenotype with airway inflammation involving both eosinophils and neutrophils, goblet cell metaplasia, airway remodeling, and elevated OVA-specific serum IgE, serum IL-17A, and BALF Th17/Th2 associated cytokines. CpG-ODNs and budesonide were found to synergistically inhibit inflammatory cell recruitment in the lung, airway remodeling, IgE synthesis, and Th17/Th2 associated cytokines. Mechanistically, CpG-ODNs and budesonide acted synergistically on BMDCs via downregulation of TSLP receptor (TSLPR) and IL-23 production, and subsequently contributed to dampen Th17/Th2 polarization in CS-associated asthma. In conclusion, combined administration of CpG-ODNs and budesonide, in a synergistic manner, inhibits airway inflammation, and tissue remodeling mediated by BMDCs by regulating IL-23 secretion and blocking TSLP signaling, which subsequently contribute to alleviate Th17/Th2 imbalance in CS-associated asthma.

The Effect of a "Class Smoke Free Pledge" on Breath Carbon Monoxide in Arabic Male Adolescents

Introduction

Arabic male adolescents have a high smoking prevalence. Introduction of "Class smoke-free" pledges have been successful amongst European adolescents but have not been evaluated using objective valid measures. We tested the impact of adding a smoke free pledge strategy to a proven peer-led asthma and smoking prevention program on breath carbon monoxide level (BCO) in male high-school students in Jordan.

Methods

We enrolled male students from four high-schools in Irbid, Jordan. Schools were randomly assigned to receive either TAJ (Triple A in Jordan, n = 218) or TAJ-Plus (with added class smoke-free pledge, n = 215). We hypothesized that students receiving TAJ-Plus would have greater reduction in BCO levels than those only receiving the TAJ intervention. Asthma and smoking status were assessed by self-administered questionnaires. Smoking outcomes were collected using a BCO Monitor.

Results

Both groups had significant reductions in BCO levels post-intervention (p < .0001), however, decreases were greater in TAJ-Plus group (3.9 ± 0.2 vs. 4.8 ± 0.2, p < .0001). Intervention effects on BCO over time did not vary by smoking status (p = .085), asthma status (p = .602), or a combination of the two (p = .702).

Conclusions

An added smoke-free pledge strategy to a proven peer-led asthma education program appears to be a promising approach to motivate adolescents to abstain from smoking in Jordan. Future research is required to determine if these results can be extended to Jordanian adolescent females.

Implications

A commitment by students via a "class smoke-free" pledge can be an added incentive to motivate adolescents in Arabic-speaking countries to abstain from smoking. Social influence approaches in schools can be useful in countering the aggressive tobacco marketing campaigns targeting Jordanian and other Arabic-speaking youth. The combination of "class smoke-free" pledges and an evidence-based peer-led asthma and smoking education can be implemented in schools to influence adolescents with asthma to abstain from smoking.

Comparisons between 2015 US asthma prevalence and two measures of asthma burden by racial/ethnic group

Objective: Asthma affects approximately 20,383,000 Americans and costs the US $56 billion dollars annually. Asthma burden is not uniform across different racial/ethnic groups. Although annual asthma prevalences by racial/ethnic group are provided by the CDC, these numbers do not account for the influence of other sociodemographic and clinical factors. In this study, we evaluated several measures of asthma burden that controlled for sociodemographic and clinical factors and compared them to 2015 CDC asthma prevalences by racial/ethnic group. Methods: We obtained unadjusted asthma predictions directly from the 2015 Behavioral Risk Factor Surveillance System (BRFSS) survey. To estimate average adjusted predictions (AAP) and adjusted predictions at the means (APM) for asthma, we controlled for sociodemographic and clinical factors through logistic models and subsequently calculated marginal probabilities for these results. Results: We found substantial differences at the national and state level between unadjusted prevalences and AAPs and APMs for asthma by race/ethnicity group. In addition, states that had the highest and lowest unadjusted prevalences differed from states that had the highest and lowest AAPs and APMs. For unadjusted prevalences, AAPs, and APMs, we found that states that had the highest prevalences or probabilities of asthma for Whites tended to have the widest disparities between the estimates for Whites and those of other races. Conclusions: The study's results highlight the need to account for sociodemographic and clinical factors when addressing asthma burden by racial/ethnic group across the US.

Prevalence, associated factors, and control level of asthma symptoms among adolescents in Northern Jordan

Objective To investigate the prevalence, associated factors, and control level of asthma in Jordanian high school students. Methods A descriptive, comparative, cross sectional design was used and a cluster sample of 2691 students (mean age = 14.5 years, 51.0% girls), drawn from eight randomly selected public high schools in Northern Jordan, participated in the study. Each student had the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire completed in the classroom between February and May, 2015. Results The prevalence of recent wheezing in the last 12 months was 11.7% whereas the prevalence of diagnosed asthma was 6.2%. About 49% of students experienced cough all the time, and 33.5% experienced waking up at night due to wheezing some of the time. About 30.9% of students reported moderate to big exercise-induced asthma. The mean total Asthma Control Test (ACT) score was 5.85 (SD = 3.56) with all of students reporting uncontrolled asthma during the last month. Higher rates of asthma symptoms were reported by females, 10th graders, and students with negative family history. Importantly, students with diagnosed asthma or recent wheezing reported higher rates of ever smoking tobacco vs. non-asthmatics (p < 0.000); dual (18.6% vs. 9.8%), cigarettes only (11.2% vs. 7.3%), and waterpipe only (18.0% vs. 14.7%). Conclusion Overall, students with asthma or wheezing had increased rates of tobacco smoking. Policies need to be set and enforced to provide a better environment for these youth, especially making all schools smoke-free zones. A multifaceted, comprehensive awareness and management program is required in schools to control and manage asthma symptoms.

Cholinergic Modulation of Type 2 Immune Responses

In recent years, the bidirectional relationship between the nervous and immune system has become increasingly clear, and its role in both homeostasis and inflammation has been well documented over the years. Since the introduction of the cholinergic anti-inflammatory pathway, there has been an increased interest in parasympathetic regulation of both innate and adaptive immune responses, including T helper 2 responses. Increasing evidence has been emerging suggesting a role for the parasympathetic nervous system in the pathophysiology of allergic diseases, including allergic rhinitis, asthma, food allergy, and atopic dermatitis. In this review, we will highlight the role of cholinergic modulation by both nicotinic and muscarinic receptors in several key aspects of the allergic inflammatory response, including barrier function, innate and adaptive immune responses, and effector cells responses. A better understanding of these cholinergic processes mediating key aspects of type 2 immune disorders might lead to novel therapeutic approaches to treat allergic diseases.

Time-Dependent Associations Between Body Composition, Physical Activity, and Current Asthma in Women: A Marginal Structural Modeling Analysis

The role of obesity in adult asthma is well-known and has been partly attributed to a confounding role of physical inactivity. However, the interrelationships between obesity, physical activity, and asthma have been incompletely addressed, probably because their time-dependent and bidirectional nature represents a methodologically challenging research question. We aimed to estimate the independent causal effects of body mass index (BMI; weight (kg)/height (m)2) and physical activity on current asthma using marginal structural models (MSMs). MSMs were applied to 15,353 adult women from a 2011 case-control study of asthma (Asthma-E3N) nested within the French E3N study (Etude Epidémiologique auprès de Femmes de la Mutuelle Générale de l'Education Nationale). Three time periods (1997-2000-2002, 2000-2002-2005, and 2002-2005-2011) were defined, where exposures (BMI and physical activity) were measured at time t, outcome (current asthma) was measured at time t + 1, and covariates were measured at time t - 1 or at baseline. A strong significant and positive dose-response relationship between BMI and current asthma was observed (odds ratios were 0.90 (95% confidence interval (CI): 0.79, 1.03), 1.29 (95% CI: 1.17, 1.42), and 1.87 (95% CI: 1.60, 2.18) for the BMI groups <20.0, 25.0-29.9, and ≥30.0, respectively, versus the normal-weight group (BMI 20.0-24.9)). We found no association between physical activity and current asthma. Our results suggest an independent causal deleterious effect of overweight and obesity on current asthma, whereas no independent causal effect of physical activity was found.

An investigation on the use of snus and its association with respiratory and sleep-related symptoms: a cross-sectional population study

INTRODUCTION

Studies of the health effects of moist oral tobacco, snus, have produced inconsistent results. The main objective of this study is to examine the health effects of snus use on asthma, respiratory symptoms and sleep-related problems, a field that has not been investigated before.

METHODS AND MATERIAL

This cross-sectional study was based on a postal questionnaire completed by 26 697 (59.3%) participants aged 16 to 75 years and living in Sweden. The questionnaire included questions on tobacco use, asthma, respiratory symptoms and sleeping problems. The association of snus use with asthma, respiratory symptoms and sleep-related symptoms was mainly tested in never-smokers (n=16 082).

RESULTS

The current use of snus in never-smokers was associated with an increased risk of asthma (OR 1.51 (95% CI 1.28 to 1.77)), asthmatic symptoms, chronic bronchitis and chronic rhinosinusitis. This association was not present among ex-snus users. Snoring was independently related to both the former and current use of snus ((OR 1.37 (95% CI 1.12 to 1.68)) and (OR 1.59 (95% CI 1.34 to 1.89), respectively)). A higher risk of difficulty inducing sleep was seen among snus users.

CONCLUSION

Snus use was associated with a higher prevalence of asthma, respiratory symptoms and snoring. Healthcare professionals should be aware of these possible adverse effects of snus use.

Geographical Disparities in the Health of Iranian Women: Health Outcomes, Behaviors, and Health-care Access Indicators

BACKGROUND

Women's health is a key factor affecting the health of the whole population. Tackling inequality in determinants of health is recognized as the main path toward reducing the inequality in health outcomes. This study aimed to analyze the provincial inequality in determinants of women's health and health care in Iran.

METHODS

Using the Moss's model (2002) as a comprehensive framework of determinants of women's health, including "geopolitical environment," "culture, norms, sanctions," "women's roles in reproduction and production," "health-related mediators," and "health outcome" categories, we chose 13 indicators. Afterward, using data sources including the Iranian Multiple Indicators of Demographics and Health Survey, the National Organization for Civil Registration, and Statistics Centre of Iran, we analyzed provincial inequality in these indicators in Iran (2011). Gini coefficient and Lorenz curve were used for measuring inequality.

RESULTS

Gini coefficients calculated as follows; life satisfaction level (0.027), literate women (0.398), women with proper knowledge about HIV/AIDS prevention (0.483), unemployed women (0.380), women without an income (0.384), women who use at least one type of mass media (0.389), women who used computer or internet (0.467), women who had received pregnancy care from a skill birth attendant (SBA) (0.420), women who had delivered with the help of an SBA (0.426), women who currently smoke cigarettes (0.603), women who currently consume hookah (0.561), women with at least one chronic disease (0.438), and women's deaths in 2010 and 2011 (0.393 and 0.359, respectively).

CONCLUSIONS

We found large provincial disparities in determinants of women's health in Iran. Determinants such as lifestyle, health behavior, health knowledge, and health-care services availability should be considered by health policymakers in addressing the inequality in women's health at a provincial level.

Neutrophilic inflammation in asthma: mechanisms and therapeutic considerations

INTRODUCTION

Neutrophilic airway inflammation represents a pathologically distinct form of asthma and frequently appears in symptomatic adulthood asthmatics. However, clinical impacts and mechanisms of the neutrophilic inflammation have not been thoroughly evaluated up to date. Areas covered: Currently, distinct clinical manifestations, triggers, and molecular mechanisms of the neutrophilic inflammation (namely Toll-like receptor, Th1, Th17, inflammasome) are under investigation in asthma. Furthermore, possible role of the neutrophilic inflammation is being investigated in respect to the airway remodeling. We searched the related literatures published during the past 10 years on the website of Pub Med under the title of asthma and neutrophilic inflammation in human. Expert commentary: Epidemiologic and experimental studies have revealed that the neutrophilic airway inflammation is induced by a wide variety of stimuli including ozone, particulate matters, cigarette smoke, occupational irritants, endotoxins, microbial infection and colonization, and aeroallergens. These triggers provoke diverse immune and inflammatory responses leading to progressive and sometimes irreversible airway obstruction. Clinically, neutrophilic airway inflammation is frequently associated with severe asthma and poor response to glucocorticoid therapy, indicating the need for other treatment strategies. Accordingly, therapeutics will be targeted against the main mediators behind the underlying molecular mechanisms of the neutrophilic inflammation.

Nicotinic acetylcholine receptor agonist attenuates ILC2-dependent airway hyperreactivity

Allergic asthma is a complex and chronic inflammatory disorder that is associated with airway hyperreactivity (AHR) and driven by Th2 cytokine secretion. Type 2 innate lymphoid cells (ILC2s) produce large amounts of Th2 cytokines and contribute to the development of AHR. Here, we show that ILC2s express the α7-nicotinic acetylcholine receptor (α7nAChR), which is thought to have an anti-inflammatory role in several inflammatory diseases. We show that engagement of a specific agonist with α7nAChR on ILC2s reduces ILC2 effector function and represses ILC2-dependent AHR, while decreasing expression of ILC2 key transcription factor GATA-3 and critical inflammatory modulator NF-κB, and reducing phosphorylation of upstream kinase IKKα/β. Additionally, the specific α7nAChR agonist reduces cytokine production and AHR in a humanized ILC2 mouse model. Collectively, our data suggest that α7nAChR expressed by ILC2s is a potential therapeutic target for the treatment of ILC2-mediated asthma.

Airway hyperreactivity is driven by type 2 cytokines produced by ILC2 and Th2 cells. Here the authors show that an α7-nicotinic receptor agonist (GTS-21) inhibits ILC2 responses and is therapeutic against Alternaria-induced airway hyperreactivity in a humanized mouse model.

Modification of additive effect between vitamins and ETS on childhood asthma risk according to GSTP1 polymorphism: a cross -sectional study

Background

Asthma is characterized by airway inflammation, and bronchial airways are particularly susceptible to oxidant-induced tissue damage.

Objective

To investigate the effect of dietary antioxidant intake and environmental tobacco smoke (ETS) on the risk of childhood asthma according to genotypes susceptible to airway diseases.

Methods

This cross-sectional study included 1124 elementary school children aged 7–12 years old. Asthma symptoms and smoking history were measured using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Intake of vitamin A (including retinol and β-carotene), C, and E was measured by a semi-quantitative food frequency questionnaire (FFQ). GSTP1 polymorphisms were genotyped from peripheral blood samples.

Results

ETS was significantly associated with presence of asthma symptoms (adjusted odds ratio [aOR], 2.48; 95 % confidence interval [CI], 1.29–4.76) and diagnosis (aOR, 1.91; 95 % CI, 1.19–3.06). Dietary antioxidant intake was not associated with asthma symptoms, although ETS plus low vitamin A intake showed a significant positive association with asthma diagnosis (aOR, 2.23; 95 % CI, 1.10–4.54). Children with AA at nucleotide 1695 in GSTP1 who had been exposed to ETS and a low vitamin A intake have an increased risk of asthma diagnosis (aOR, 4.44; 95 % CI,1.58–12.52) compared with children who had not been exposed to the two risk factors. However, ETS exposure and low vitamin A intake did not significantly increase odds of asthma diagnosis in children with AG or GG genotypes.

Conclusion

Low vitamin A intake and ETS exposure may increase oxidative stress and thereby risk for childhood asthma. These relationships may be modified by gene susceptibility alleles of GSTP1.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0093-0) contains supplementary material, which is available to authorized users.

The need to differentiate between adults and children when treating severe asthma

Severe asthma at all ages is heterogeneous incorporating several phenotypes that are distinct in children and adults, however, there are also numerous similar features including the limitation that they may not remain stable longitudinally. Severe asthma in both children and adults is characterized by eosinophilic airway inflammation and evidence of airway remodeling. In adults, targeting eosinophilia with anti-IL-5 antibody therapy is very successful, resulting in the recommendation that sputum eosinophils should be used to guide treatment. In contrast, data for the efficacy of blocking IL-5 remain unavailable in children. However, its effectiveness is uncertain since many children with severe asthma have normal blood eosinophils and the dominance of Th2-mediated inflammation is controversial. Approaches that have revealed gene signatures and biomarkers such as periostin that are specific to adult disease now need to be adopted in children to identify effective pediatric specific therapeutics and minimize the extrapolation of adult therapeutics to children.

Genomewide association study identifies HAS2 as a novel susceptibility gene for adult asthma in a Japanese population

BACKGROUND

It is increasingly clear that asthma is not a single disease, but a disorder with vast heterogeneity in pathogenesis, severity, and treatment response. To date, 30 genomewide association studies (GWASs) of asthma have been performed, including by our group. However, most gene variants identified so far confer relatively small increments in risk and explain only a small proportion of familial clustering.

OBJECTIVE

To identify additional genetic determinants of susceptibility to asthma using a selected Japanese population with reduced tobacco smoking exposure.

METHODS

We performed a GWAS by genotyping a total of 480 098 single-nucleotide polymorphisms (SNPs) for a Japanese cohort consisting of 734 healthy controls and 240 patients with asthma who had smoked for no more than 10 pack-years. The SNP with the strongest association was genotyped in two other independent Japanese cohorts consisting of a total of 531 healthy controls and 418 patients with asthma who had smoked for no more than 10 pack-years. For the hyaluronan synthase 2 (HAS2) gene, we investigated SNP-gene associations using an expression quantitative trait loci (eQTL) database and also analysed its gene expression profiles in 13 different normal tissues.

RESULTS

In the discovery GWAS, a SNP located upstream of HAS2, rs7846389, showed the strongest statistical significance (P = 1.43 × 10(-7) ). In the two independent replication cohorts, rs7846389 was consistently associated with asthma (nominal P = 0.0152 and 0.0478 in the first and second replication cohorts, respectively). In the meta-analysis, association of rs7846389 with susceptibility to asthma reached the level of genomewide significance (P = 7.92 × 10(-9) ). This variant was strongly correlated with HAS2 mRNA expression. The strongest expression of the gene was detected in the lung.

CONCLUSIONS

Our study identified HAS2 as a novel candidate gene for susceptibility to adult asthma.

Effects of cigarette smoking on rhinologic diseases: Korean National Health and Nutrition Examination Survey 2008-2011

BACKGROUND

Several studies have shown a relationship between cigarette smoking and general diseases of the nose in a large Asian population. The current study was conducted to better understand the effect of cigarette smoke exposure on rhinologic diseases in Koreans.

METHODS

Data were obtained from the 2008-2011 Korea National Health and Nutrition Examination Survey, a cross-sectional survey of the noninstitutionalized population in Korea. Of the 37,753 people surveyed, 11,589 adult participants had completed questionnaires on rhinologic symptoms and smoking behaviors, had undergone nasal endoscopy, and had provided urine collection were enrolled. Rhinologic diseases investigated in this study included subjective olfactory dysfunction, rhinitis symptoms, chronic rhinosinusitis (CRS), and nasal septal deviation with obstructive symptoms. The relationship between disease and cigarette smoking was evaluated using multivariate regression analyses.

RESULTS

In South Korea, the weighted prevalence of subjective olfactory dysfunction, rhinitis symptoms, CRS, and nasal septal deviation with obstructive symptoms was 4.6%, 27.2%, 6.2%, and 4.0%, respectively. The only disease significantly associated with active smoking was CRS in participants 40 years of age and older after adjusting for age, sex, residency, house income, education, and occupation (adjusted odds ratio = 1.427, 95% confidence interval = 1.050 to 1.938). For each year of active smoking, CRS prevalence increased by 1.5%. None of the rhinologic diseases examined were associated with passive smoking.

CONCLUSION

Our study showed that CRS seems to be associated with active smoking in older participants. Considering the relatively high prevalence of CRS in Korea, further longitudinal researches for their association and prevention are required.

Decline in asthma prevalence and severity in Israel over a 10-year period

BACKGROUND

The prevalence of asthma has increased in western countries towards the end of the last century, but recently seems to have stabilized.

OBJECTIVE

To evaluate trends in the prevalence and severity of asthma that occurred in Israel over the past decade.

METHODS

The medical records of 17-year-old boys, eligible for national service, between 1999 and 2008 were reviewed. National annual hospitalization and death rates for asthma were extracted.

RESULTS

Three hundred thousand medical records were reviewed. During the study period, lifetime asthma prevalence decreased from 9.7 to 8.1% (p = 0.002). The point prevalence of moderate-to-severe and mild persistent asthma decreased significantly from 0.88 and 3.41% to 0.36 and 2.44%, respectively, during this period. The prevalence of intermittent asthma and asthma in clinical remission for more than 3 years did not change significantly. The annual hospitalization rate for asthma decreased from 13.0 to 7.5 per 10,000 population (p < 0.0001), whilst the annual death rate due to asthma decreased between 1999 and 2008 from 2.1 to 1.4 per 100,000 population (p = 0.003).

CONCLUSIONS

The prevalence of asthma in Israeli teenage boys decreased significantly over the last decade. In addition, asthma hospitalization and asthma-related death rates in the total population also decreased.

Intrauterine exposure to smoking and wheezing in adolescence: the 1993 Pelotas Birth Cohort

Previous studies have suggested an association between maternal smoking during pregnancy and asthma symptoms such as wheezing during childhood. However, few have evaluated this association in adolescence, especially in populations with high prevalence of wheezing as in Brazil. Using the 1993 Pelotas birth cohort, a longitudinal study set in southern Brazil of 5249 urban live births, we aimed to evaluate the association between maternal and the partner's smoking during pregnancy and wheezing at 11 and 15 years of age. We evaluated smoking during pregnancy using number of cigarettes/day, and our main outcomes were as follows: wheezing in the last year and number of wheezing crises, at both 11 and 15 years of age, as well as persistent wheezing (having crises at 11 and 15 years of age) and medical asthma diagnosis at age 15. In addition, other socio-demographic variables were included as possible confounders and mediators of this association. We used Poisson regression models to evaluate crude and adjusted associations. Of the 5249 live births in 1993, 87.5% and 85.7% were followed-up to 11 and 15 years of age, respectively. Maternal smoking during pregnancy showed a dose-response association with number of wheezing crises at age 15 (P = 0.023), presence of persistent wheezing (P = 0.034) and asthma diagnosis (P = 0.023). Partner's smoking was not associated with any wheezing variables. Maternal smoking during pregnancy appears to exert an effect on respiratory morbidity of adolescents, evaluated by wheezing symptoms.

Prevalence, patterns and correlates of cigarette smoking in male adolescents in northern Jordan, and the influence of waterpipe use and asthma diagnosis: a descriptive cross-sectional study

Our study investigates the prevalence, patterns and predictors of tobacco smoking among early adolescent males in Northern Jordan and whether asthma diagnosis affects smoking patterns. A descriptive cross sectional design was used. Males in grades 7 and 8 from four randomly selected high schools in the city of Irbid were enrolled. Data on waterpipe (WP) use and cigarette smoking patterns were obtained (n = 815) using a survey in Arabic language. The overall prevalence of ever having smoked a cigarette was 35.6%, with 86.2% of this group smoking currently. Almost half of the sample reported WP use. The most common age in which adolescents started to experiment with cigarettes was 11–12 years old (49.1%), although 10 years was also common (25.3%). Significant predictors of male cigarette smoking were WP use (OR = 4.15, 95% CI = 2.99–5.76), asthma diagnosis (OR = 2.35, 95% CI = 1.46–3.78), grade 8 (OR = 1.52, 95% CI = 1.10–2.11), and having a sibling who smokes (OR = 2.23, 95% CI = 1.53–3.24). However, this cross-sectional study cannot establish causality, thus longitudinal studies are needed. Public health programs and school-based anti-tobacco smoking interventions that target children in early years at high schools are warranted to prevent the uptake of tobacco use among this vulnerable age group. High school students with asthma should be specifically targeted.

Predictors for the development of progressive severity in new-onset adult asthma

BACKGROUND

A proportion of patients with adult-onset asthma have severe disease. Risk factors for an increase in asthma severity are poorly known.

OBJECTIVE

We sought to identify predictors for the development of severe asthma in adults.

METHODS

A cohort of 200 adults with new-onset asthma was prospectively followed for 2 years. At baseline, patients underwent a comprehensive assessment of clinical, functional, and inflammatory parameters. After 2 years, change in asthma severity was assessed by using the Global Initiative for Asthma score (range, 1-4), which is based on asthma control (Asthma Control Questionnaire), lung function (FEV1), and inhaled corticosteroid requirement. ANOVA and multiple regression equations were used in the analysis.

RESULTS

One hundred twenty-eight patients completed 2 years of follow-up. Seventeen (13.3%) patients had an increase in asthma severity, whereas 53 (41.4%) patients had a decrease. A lower postbronchodilator FEV1/forced vital capacity ratio and a higher number of cigarette pack years smoked at baseline were significantly associated with an increase in asthma severity at follow-up. Multiple regression equations showed that only the number of cigarette pack years smoked was independently associated with an increase in asthma severity, with an odds ratio of 1.4 (95% CI, 1.02-1.91) for every 10 pack years smoked.

CONCLUSION

A history of cigarette smoking in patients with new-onset adult asthma predicts an increase in asthma severity during the first 2 years of the disease in a dose-dependent manner.

Defining severe asthma - an approach to find new therapies

Asthma is a chronic inflammatory disease that has reached epidemic proportions worldwide. It is treatable in the majority of patients, but there is no cure. Moreover, a proportion of patients suffer from severe, difficult-to-control disease with daily symptoms and high morbidity, making it imperative that we continue to improve our understanding of the underlying mechanisms of this disease. Severe asthma is a heterogeneous condition. A systematic approach to identify specific asthma phenotypes, including clinical characteristics and inflammatory processes, is the first step toward individualized, logical therapy. This review focuses on the need to characterize severe asthma phenotypes and on novel, targeted molecular treatment options currently under development.

Transforming growth factor-beta 1 pathways in inflammatory airway diseases

Transforming growth factor-beta 1 (TGF-β1) has been reported being involved in the remodeling and immunosuppression processes of inflammatory airway diseases; understanding the regulation of TGF-β1 is therefore a key to unravel the pathomechanisms of these diseases. This review briefly summarizes the current knowledge on the influencing factors for driving TGF-β1 and its regulatory pathways in inflammatory airway diseases and discusses possible therapeutic approaches to TGF-β1 control. The factors include smoking and oxidative stress, prostaglandins (PGs), leukotrienes (LTs), bradykinin (BK), and microRNAs (miRs). Based on the summary, new innovative treatment strategies may be developed for inflammatory airway diseases with an impaired expression of TGF-β1.

Passive smoking impairs histone deacetylase-2 in children with severe asthma

Background:

Parental smoking is known to worsen asthma symptoms in children and to make them refractory to asthma treatment, but the molecular mechanism is unclear. Oxidative stress from tobacco smoke has been reported to impair histone deacetylase-2 (HDAC2) via phosphoinositide-3-kinase (PI3K)/Akt activation and, thus, to reduce corticosteroid sensitivity. The aim of this study was to investigate passive smoking-dependent molecular abnormalities in alveolar macrophages (AMs) by comparing passive smoke-exposed children and non-passive smoke-exposed children with uncontrolled severe asthma.

Methods:

BAL fluid (BALF) was obtained from 19 children with uncontrolled severe asthma (10 non-passive smoking-exposed subjects and nine passive smoking-exposed subjects), and HDAC2 expression/activity, Akt/HDAC2 phosphorylation levels, and corticosteroid responsiveness in AMs were evaluated.

Results:

Parental smoking reduced HDAC2 protein expression by 54% and activity by 47%, with concomitant enhancement of phosphorylation of Akt1 and HDAC2. In addition, phosphorylation levels of Akt1 correlated positively with HDAC2 phosphorylation levels and negatively with HDAC2 activity. Furthermore, passive smoke exposure reduced the inhibitory effects of dexamethasone on tumor necrosis factor-α-induced CXCL8 release in AMs. There were relatively higher neutrophil counts and CXCL8 concentrations in BALF and lower Asthma Control Test scores compared with non-passive smoke-exposed children with uncontrolled severe asthma.

Conclusions:

Passive smoking impairs HDAC2 function via PI3K signaling activation, which could contribute to corticosteroid-insensitive inflammation in children with severe asthma. This novel mechanism will be a treatment target in children with severe asthma and stresses the need for a smoke-free environment for asthmatic children.

Associations between selected allergens, phthalates, nicotine, polycyclic aromatic hydrocarbons, and bedroom ventilation and clinically confirmed asthma, rhinoconjunctivitis, and atopic dermatitis in preschool children

Previous studies, often using data from questionnaires, have reported associations between various characteristics of indoor environments and allergic disease. The aim of this study has been to investigate possible associations between objectively assessed indoor environmental factors and clinically confirmed asthma, rhinoconjunctivitis, and atopic dermatitis. The study is a cross-sectional case-control study of 500 children aged 3-5 years from Odense, Denmark. The 200 cases had at least two parentally reported allergic diseases, while the 300 controls were randomly selected from 2835 participating families. A single physician conducted clinical examinations of all 500 children. Children from the initially random control group with clinically confirmed allergic disease were subsequently excluded from the control group and admitted in the case group, leaving 242 in the healthy control group. For most children, specific IgE's against various allergens were determined. In parallel, dust samples were collected and air change rates were measured in the children's bedrooms. The dust samples were analyzed for phthalate esters, polycyclic aromatic hydrocarbons (PAH), nicotine, and various allergens. Among children diagnosed with asthma, concentrations of nicotine were higher (P < 0.05) and cat allergens were lower (P < 0.05) compared with the healthy controls; air change rates were lower for those sensitized (specific IgE+) compared with those not sensitized (specific IgE-, P < 0.05); and dust mite allergens were higher for specific IgE+ cases compared with healthy controls (P < 0.05). When disease status was based solely on questionnaire responses (as opposed to physician diagnosis), significant associations were found between di(2-ethylhexyl) phthalate (DEHP) and dog allergens in dust and current wheeze.

Prevalence of asthmatic smokers: Turkish experience (PASTE Study)

BACKGROUND

Although both asthma and smoking are major health problems worldwide, smokers are often excluded from asthma studies.

OBJECTIVES

It was aimed to verify the prevalence of asthmatic smokers in Turkey and assess the effects of smoking based on clinical parameters, exacerbations and hospitalizations because of lack of national data about the prevalence of smoking among asthmatics.

METHODS

The study protocol was comprised of a retrospective questionnaire. The asthmatic patients were followed in the outpatient clinics of 18 tertiary hospitals selected from seven different geographical regions in Turkey. We evaluated demographic data, smoking habits, asthma-related diseases, respiratory function and emergency visits.

RESULTS

The study population included 1385 patients (M/F: 343/1042), and the mean age was 45.1 ± 14.0 years. Current and former smoking prevalence was 11.4% and 15.1%, respectively. Smoker rates were higher in males and younger asthmatics compared with females and older asthmatics (P < 0.01 and P < 0.05, respectively). Smoking history ranged from 0.20 to 90 pack-years (the mean was 12.9), and smokers had a higher level of education compared with nonsmokers (P < 0.01). Socioeconomically, the most developed region had the highest rate of smoker asthmatics (33.9%; P = 0.014). There was an increase in the number of exacerbations in smoker asthmatics during the previous year, but it was not statistically significant (P > 0.05).

CONCLUSION

We showed that the smoking prevalence in Turkey was lower in asthmatics (11.4%) compared with the general population (44.5%). Nevertheless, every effort should be made to encourage asthmatics to stop smoking because smoking is a modifiable risk factor for adverse asthma health outcomes.

Brain-derived neurotrophic factor in cigarette smoke-induced airway hyperreactivity

Enhanced airway smooth muscle (ASM) contractility contributes to increased resistance to airflow in diseases such as bronchitis and asthma that occur in passive smokers exposed to secondhand smoke. Little information exists on the cellular mechanisms underlying such airway hyperreactivity. Sputum samples of patients with chronic sinusitis, bronchitis, and asthma show increased concentrations of growth factors called neurotrophins, including brain-derived growth factor (BDNF), but their physiological significance remains unknown. In human ASM, we tested the hypothesis that BDNF contributes to increased contractility with cigarette smoke exposure. The exposure of ASM to 1% or 2% cigarette smoke extract (CSE) for 24 hours increased intracellular calcium ([Ca(2+)](i)) responses to histamine, and further potentiated the enhancing effects of a range of BDNF concentrations on such histamine responses. CSE exposure increased the expression of the both high-affinity and low-affinity neurotrophin receptors tropomyosin-related kinase (Trk)-B and p75 pan-neurotrophin receptor, respectively. Quantitative ELISA showed that CSE increased BDNF secretion by human ASM cells. BDNF small interfering (si)RNA and/or the chelation of extracellular BDNF, using TrkB-fragment crystallizable, blunted the effects of CSE on [Ca(2+)](i) responses as well as the CSE enhancement of cell proliferation, whereas TrkB siRNA blunted the effects of CSE on ASM contractility. These data suggest that cigarette smoke is a potent inducer of BDNF and TrkB expression and signaling in ASM, which then contribute to cigarette smoke-induced airway hyperresponsiveness.

Environmental tobacco smoke exposure at home and smoking prevalence in the general Portuguese population--the INAsma study

BACKGROUND

We aimed to: 1) estimate the prevalence of exposure to environmental tobacco smoke (ETS) at home in the Portuguese population; 2) estimate tobacco smoking prevalence in Portugal; 3) identify social and personal characteristics associated with smoking or exposure to ETS.

METHODS

Nationwide, cross-sectional, population-based telephone survey. Overall, 6003 individuals completed the interview. ETS exposure at home was defined as exposure to at least one current smoker at home. A smoker was defined as someone with 15 years or older, smoking at least 1 cigarette per day during a year; a current smoker (CS) smoked in the last month.

RESULTS

Exposure to ETS at home was reported by 26.6% (95%CI 25.5-27.7) of the participants. Living in households with ≥4 persons (OR=2.31; 95%CI[1.81-2.96]), being a current smoker (OR=7.29; 95%CI[5.74-9.26]) or having current asthma (OR=2.06; 95%CI[1.45-2.94]) were factors positively associated with ETS exposure. When analyzed by gender, the effect of current asthma was only relevant to females. Currently 19.0% (95%CI 18.0-20.0) of the Portuguese population smokes tobacco and 17.2% (95%CI 16.2-18.2) are ex-smokers. CS prevalence is higher in males than females (26.5%versus 12.2%, p<0,001). The odds of being a CS were higher for males, the more educated, and those exposed to ETS at home. When analyzed by gender, school education only affected females.

CONCLUSION

Exposure to ETS at home was higher than previously reported. Children/adolescents and asthma patients may have a higher risk of exposure. This report endorses a decreasing trend in the prevalence of tobacco smoking in Portuguese males, but a tendency to increase in females.

Impact of parental smoking on childhood asthma

OBJECTIVE

To evaluate the exposure to environmental tobacco smoke (ETS) of the childhood population in this community and its relationship with asthma symptoms.

METHODS

A cross-sectional study was conducted using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on children and adolescents in this community. The symptoms "wheezing ever", "current asthma", "severe asthma", and "exercise-induced asthma" were defined by this questionnaire. Parental smoking was classified into four mutually exclusive categories: 1) no parent smokes; 2) only the mother smokes; 3) only the father smokes; and 4) both parents smoke. The odds ratio of the prevalence of asthma symptoms according to ETS exposure was calculated using logistic regression.

RESULTS

A total of 10,314 children and 10,453 adolescents were included. Over 51% of the children and adolescents were exposed to ETS at home. ETS is associated with a higher prevalence of asthma symptoms, particularly if the mother or both parents smoke.

CONCLUSION

The prevalence of ETS is still high in this community, although there has been a decreasing tendency in the last 15 years. ETS is associated with higher prevalence of asthma.