Is the prevalence of asthma declining? Systematic review of epidemiological studies

Novel bronchodilatory quinazolines and quinoxalines: synthesis and biological evaluation

A series of heterocyclic derivatives analogous to (-)vasicinone, in which the vasicinone C-ring was replaced with alkyl chain terminated by tertiary amine was prepared. N3, C4-O, C4-S or C4-N were used as the sites of attachment. The 4-[3-(1-piperidyl)propylsulfanyl]derivatives displayed bronchodilatory effect at low micromolar concentrations on isolated rat trachea, and low toxicity both on Balb/c 3T3 mouse fibroblast cells and in mice.

The epidemiology of food allergy in Europe: a systematic review and meta-analysis

Food allergy (FA) is an important atopic disease although its precise burden is unclear. This systematic review aimed to provide recent, up-to-date data on the incidence, prevalence, time trends, and risk and prognostic factors for FA in Europe. We searched four electronic databases, covering studies published from 1 January 2000 to 30 September 2012. Two independent reviewers appraised the studies and qualified the risk of bias using the Critical Appraisal Skills Programme tool. Seventy-five eligible articles (comprising 56 primary studies) were included in a narrative synthesis, and 30 studies in a random-effects meta-analysis. Most of the studies were graded as at moderate risk of bias. The pooled lifetime and point prevalence of self-reported FA were 17.3% (95% CI: 17.0-17.6) and 5.9% (95% CI: 5.7-6.1), respectively. The point prevalence of sensitization to ≥1 food as assessed by specific IgE was 10.1% (95% CI: 9.4-10.8) and skin prick test 2.7% (95% CI: 2.4-3.0), food challenge positivity 0.9% (95% CI: 0.8-1.1). While the incidence of FA appeared stable over time, there was some evidence that the prevalence may be increasing. There were no consistent risk or prognostic factors for the development or resolution of FA identified, but sex, age, country of residence, familial atopic history, and the presence of other allergic diseases seem to be important. Food allergy is a significant clinical problem in Europe. The evidence base in this area would benefit from additional studies using standardized, rigorous methodology; data are particularly required from Eastern and Southern Europe.

Preterm birth and childhood wheezing disorders: a systematic review and meta-analysis

BACKGROUND

Accumulating evidence implicates early life factors in the aetiology of non-communicable diseases, including asthma/wheezing disorders. We undertook a systematic review investigating risks of asthma/wheezing disorders in children born preterm, including the increasing numbers who, as a result of advances in neonatal care, now survive very preterm birth.

METHODS AND FINDINGS

Two reviewers independently searched seven online databases for contemporaneous (1 January 1995-23 September 2013) epidemiological studies investigating the association between preterm birth and asthma/wheezing disorders. Additional studies were identified through reference and citation searches, and contacting international experts. Quality appraisal was undertaken using the Effective Public Health Practice Project instrument. We pooled unadjusted and adjusted effect estimates using random-effects meta-analysis, investigated "dose-response" associations, and undertook subgroup, sensitivity, and meta-regression analyses to assess the robustness of associations. We identified 42 eligible studies from six continents. Twelve were excluded for population overlap, leaving 30 unique studies involving 1,543,639 children. Preterm birth was associated with an increased risk of wheezing disorders in unadjusted (13.7% versus 8.3%; odds ratio [OR] 1.71, 95% CI 1.57-1.87; 26 studies including 1,500,916 children) and adjusted analyses (OR 1.46, 95% CI 1.29-1.65; 17 studies including 874,710 children). The risk was particularly high among children born very preterm (<32 wk gestation; unadjusted: OR 3.00, 95% CI 2.61-3.44; adjusted: OR 2.81, 95% CI 2.55-3.12). Findings were most pronounced for studies with low risk of bias and were consistent across sensitivity analyses. The estimated population-attributable risk of preterm birth for childhood wheezing disorders was ≥3.1%. Key limitations related to the paucity of data from low- and middle-income countries, and risk of residual confounding.

CONCLUSIONS

There is compelling evidence that preterm birth-particularly very preterm birth-increases the risk of asthma. Given the projected global increases in children surviving preterm births, research now needs to focus on understanding underlying mechanisms, and then to translate these insights into the development of preventive interventions.

REVIEW REGISTRATION

PROSPERO CRD42013004965.

Food and nutrition insecurity: a marker of vulnerability to asthma symptoms

OBJECTIVE

To evaluate the association between food and nutrition insecurity and asthma in children from Latin America.

DESIGN

Cross-sectional study.

SETTING

São Francisco do Conde, Bahia, north-eastern Brazil.

SUBJECTS

The study included 1307 children aged 6-12 years from public elementary schools. Asthma symptoms were collected using a questionnaire that was translated and adapted from the International Study of Asthma and Allergies in Childhood, phase III. The diagnosis of asthma was determined based on reports of wheezing in the previous 12 months. The Brazilian Food Insecurity Scale was used to identify food insecurity. We also obtained demographic, socio-economic and anthropometric information for each participant. We used multivariate logistic regression analyses to assess the associations of interest.

RESULTS

Of the children surveyed, 10·4% had a history of wheezing and 64·5% had some degree of food and nutrition insecurity. We found a positive dose-response relationship and statistically significant associations of asthma with moderate (OR = 1·71, 95% CI 1·01, 2·89) and severe (OR = 2·51, 95% CI 1·28, 4·93) food and nutrition insecurity.

CONCLUSIONS

The results show that moderate and severe food and nutrition insecurity are markers of vulnerability to wheezing. It is important to note that the results of studies in this field have potential implications for social policies that promote food security. Further studies to identify the mechanisms involved in the relationship between food and nutrition insecurity and asthma are needed.

Use of breath-actuated inhalers in patients with asthma and COPD - an advance in inhalational therapy: a systematic review

The pressurized metered dose inhalers and dry powder inhalers are the most widely used devices for inhalation therapy in asthma and chronic obstructive pulmonary disease; each of these devices have certain advantages and disadvantages that impact their use. Motivation from the virtues of these devices led to the development of breath-actuated or breath-activated metered dose inhalers. A history of the breath-actuated inhalers, the development and technical aspects, studies about the usability, inhalation technique and patient preference, lung deposition and impact on lung function are presented in this review article. This review presents the use of breath-actuated inhalers in asthma and chronic obstructive pulmonary disease and in children and elderly; and a brief economic evaluation aims to put the clinical efficacy and ease-of-use of the breath-actuated inhaler into perspective by understanding the long-term cost benefits associated with this device.

Prevalence of IgE sensitization in Danish children with suspected asthma

OBJECTIVE

The aim of this article was to estimate the prevalence of IgE sensitization in Danish children with suspected asthma and to characterize the pattern of sensitization.

STUDY DESIGN

We performed a cross-sectional study including 1744 children from 0 to 15 yr suspected of asthma who were referred to pediatric outpatient clinics in the region of southern Denmark from 2003 to 2005. The children were subjected to an extensive questionnaire-based interview, clinical examination, and both skin prick testing (SPT) and IgE measurements for 17 allergens.

RESULTS

Asthma was confirmed in 1024 of the 1744 children. Among the children in whom the asthma diagnosis was confirmed, sensitization to one or more of the 17 allergens tested was found in 67.5% by either SPT or s-IgE ≥ class 2. Sensitization to any food allergen was found in 31.1%, to any outdoor allergen in 36.2%, and to any indoor allergen in 51.8%. Sensitization to cockroach and latex was rare. We found a weak correlation between SPT and s-IgE among food allergens and a more distinct correlation among inhalant allergens. Surprisingly, 30.1% of children in whom the asthma diagnosis was disproven used inhaled corticosteroids (ICS). On the contrary, 32.5% of the children for whom the asthma diagnosis was verified were not treated with ICS.

CONCLUSION

We have found a high prevalence of sensitization among children with verified asthma. Our study supports relevant allergy testing in all children with verified asthma and emphasizes the importance of a thorough asthma diagnosis before prescribing continuous inhaled corticosteroids to children.

Antibiotic exposure in the first two years of life and development of asthma and other allergic diseases by 7.5 yr: a dose-dependent relationship

BACKGROUND

Antibiotic use in infancy disrupts gut microflora during a critical period for immune system development. It is hypothesized that this could predispose to the development of allergic diseases. We investigated the associations of antibiotic use in the first 2 yr of life with the development of asthma, eczema or hay fever by age 7.5 yr in a longitudinal birth cohort.

METHODS

Subjects were 4952 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Child antibiotic use and asthma, eczema and hay fever symptoms were maternally reported. Atopy was assessed by skin prick tests at age 7.5 yr. The total number of antibiotic courses was considered as the main exposure. Data were analysed using multivariate logistic regression.

RESULTS

Children reported to have taken antibiotics during infancy (0-2 yr) were more likely to have asthma at 7.5 yr (OR 1.75, 95% CI 1.40-2.17), and the odds (OR, [95% CI]) increased with greater numbers of courses: once 1.11 [0.84-1.48]; twice 1.50 [1.14-1.98]; three times 1.79 [1.34-2.40]; four times or more 2.82 [2.19-3.63]. Increased antibiotic use was also associated with higher odds of eczema and hay fever but not atopy. The effect appeared to be associated with cumulative rather than a critical period of exposure during the first 2 yr.

CONCLUSIONS

A robust and dose-dependent association was found between antibiotic use in the first 2 yr of life and asthma at age 7.5 yr but did not appear to be mediated through an association with atopy.

Association study of mitochondrial genetic polymorphisms in asthmatic children

It has been suggested that mitochondrial dysfunction plays a role in the pathogenesis of asthma. To test whether mitochondrial variants influence the risk of asthma, we analyzed 16,158 mtSNPs in a sample of 372 asthmatic children and 395 healthy children using the DNA pooling technique and genome wide association analysis. Stratified analysis by sex was performed to explain the differences observed between sexes in the etiology of asthma. Different variants were detected to be significant in the sample of girls and boys with the smallest adjusted p values being 1.4 × 10(-09) (mt5295) and 3.6 × 10(-12) (mt16158), respectively. Most of the significant locations found in boys are within the CYB gene and the non-coding region. For girls, most of the significant mtSNPs lie within NADH-dehydrogenase-subunits. The variants reported here have not previously been described in connection with asthma. Although further studies in other cohorts are needed to confirm these findings our study highlights the importance of the mitochondria among the factors that contribute to the risk of asthma.

Asthma prevalence and risk factors among children and adolescents living around an industrial area: a cross-sectional study

Background

The exposure to air pollution has negative effects on human health, increasing the risk of respiratory diseases, such as asthma. Few data are yet available on the epidemiology of childhood asthma in some areas of Italy. The aim of the study was to estimate asthma prevalence and related risk factors in children and adolescents residents around the industrial area of Termoli, Molise region, Central-South Italy.

Methods

Prevalence was assessed through the administration of modified ISAAC questionnaires filled out by parents of 89 children and adolescents for the identification of confirmed and probable cases, and by analyzing pediatricians’ databases on drug prescriptions for symptoms control and treatment of assisted population in the study area (n = 1,004), compared to a control area (n = 920) with lower industrialization. The association of asthma with risk factors was evaluated by univariate (Chi-square or Fisher’s Exact test) and regression logistic analysis.

Results

A total of 22 (24.7%) asthmatics were identified, including both confirmed (n = 7; 7.9%) and probable cases (n = 15; 16.8%), most of them (n = 17; 77.3%) resident of Termoli town. All asthma cases were georeferenced based on the residence, however clusters were not found. Using drug prescriptions analysis, a higher prevalence (n = 138; 13.7%) of diagnosed cases was found. Lifetime history of both atopic dermatitis and bronchitis were significantly relateds to asthma cases, as well as an elevated body mass index, whose association is consistent with prevalence data of overweight/obese children living in the study area. Moreover, being resident of the town of Termoli was associated to the occurrence of cases.

Conclusions

Although our data indicated a prevalence concordance with previous national studies in pediatric population, a definitive correlation with environmental industrial factors present in the study area was not established. However, asthma outcome was significantly associated to individuals living in the town of Termoli that, despite the industrial/manufacturing activities, is also subjected to a higher environmental pressure due to the presence of toll road, state highway, railroad, and seaport which may cause air pollution from motor vehicle traffic and increase asthma induction. This study provides hitherto unavailable data on asthma in childhood population living in an industrialized area which was never investigated before, could be part of a systematic review or meta-analysis procedure, might suggest significant findings for larger observational studies, and contribute to complete the frame of disease epidemiology in Italy.

A cross-sectional analysis of pet-specific immunoglobulin E sensitization and allergic symptomatology and household pet keeping in a birth cohort population

It is unknown whether family members with detectable specific immunoglobulin E (sIgE) and/or allergic symptoms to pets are more or less likely to reside in a household with pets. We cross-sectionally investigated potential relationships between family members' allergic sensitization and symptoms to dogs and cats and current household pet-keeping practices, using birth cohort data. Blood samples taken from children enrolled in a birth cohort and their biological mothers and fathers, when the children were aged 18 years, were assessed for sIgE to dog and cat allergens. Interviews assessed subjects' self-reported pet exposure symptoms, current household pet-keeping practices, and socioeconomic characteristics. Overall, household dog or cat keeping was not associated with sIgE to these animals and/or self-reported allergic symptoms in the presence of these animals, even after controlling for factors such as education and household income. In subgroup analyses, current household dog keeping among dog-symptomatic teens (n = 40) was significantly lower than among teens who were not dog symptomatic (n = 289), at 48.8 and 61.1%, respectively (p = 0.036). Current household cat keeping was significantly lower among cat-symptomatic mothers (n = 27) compared with mothers who were not cat symptomatic (n = 120), at 24.3 and 37.0%, respectively (p = 0.015). However, when considering those who were both sensitized and reported symptoms, only the mother and cat-keeping associations persisted (p = 0.049). When cat-sensitized mothers report allergic symptoms to cats, these pets may be less likely to be kept in homes. Elevated dog and cat allergen sIgE does not appear to be associated with the keeping of these pets.

Use of acid-suppressive drugs in pregnancy and the risk of childhood asthma: bidirectional crossover study using the general practice research database

BACKGROUND

Recent studies have reported an association between maternal use of gastric acid-suppressive drugs during pregnancy and asthma in the offspring, but the association could have been confounded by unmeasured risk factors.

OBJECTIVE

We assessed the association between the use of acid-suppressive drugs during pregnancy and the risk of developing childhood asthma using a bidirectional crossover design.

METHODS

Mother-infant matched sets in the UK General Practitioners Research Database were used to identify children with a drug-treated asthma diagnosis during the years 2006-2010 who were matched to a sibling without asthma as controls. Primary exposure was use of any anti-suppressive drug during pregnancy, and subgroup analyses were conducted according to drug class (e.g. proton pump inhibitors or histamine 2 receptor antagonists) and trimester. Conditional logistic regression was used to estimate odds ratios (OR) with their corresponding 95 % confidence intervals (CIs).

RESULTS

A total of 1,874 children with asthma and 1,874 control siblings were included in the analysis. The exposure rate among case and control pregnancies was 22 and 20 %, respectively. After adjustments for gender, birth order, mother's age and general practice visits, the exposure to any gastric-acid suppressive drug during pregnancy slightly increased the risk for developing asthma (OR 1.23, 95 % CI 1.01-1.51; p = 0.042). A trend towards increased risks was observed for those who used proton pump inhibitors and/or histamine 2 receptor antagonists (adjusted OR 1.72, 95 % CI 1.00-2.98; p = 0.048).

CONCLUSIONS

These findings lend support to the emerging evidence that exposure to acid-suppressive drugs during pregnancy is associated with childhood asthma. More basic research is now warranted to investigate the mechanisms.

Development of atopic disease and disturbed sleep in childhood and adolescence--a longitudinal population-based study

BACKGROUND

Both atopic diseases and sleep disturbances have increased during recent decades, especially in children. Sleep is important for many aspects of immune regulation relevant in allergic diseases, and sleep disturbances are common in patients with such diseases. A connection between sleep disturbances and fatigue, and atopic disease is well established. However, the time course and putative causal relationships between these factors are obscure.

OBJECTIVE

We aimed at investigating the developmental relationships between subjectively reported sleep disturbances and symptoms of atopic disease, from childhood to adolescence.

METHODS

This longitudinal study used parent-report questionnaire data on symptoms of atopic disease, and sleep disturbances, from the Twin Study of Child and Adolescent Development (TCHAD). Overall, 1480 twin pairs born in Sweden were approached first when children were 8-9 years old, and again later at 13-14 years old. Response rates were 75% and 72%. Data from the TCHAD questionnaires were linked to the Swedish Medical Birth Register based on personal identification numbers.

RESULTS

Being overtired at age 8 increased the risk [OR; 95% CI (2.59; 1.31-5.11)] to develop rhinitis symptoms at age 13, even when controlling for gender, previous rhinitis, Socio-economic status, birth weight and other sleep disturbances at age 8. Likewise, symptoms of asthma at age 8 was an independent risk factor for being overtired at age 13 [OR; 95% CI (2.64; 1.44-4.84)], controlling for similar confounders.

CONCLUSION & CLINICAL RELEVANCE

The findings from this study are consonant with the proposition that atopic disease and disturbed sleep are more than passively interrelated. Future research needs to delineate whether causal relationships between these problems are at hand and, if so, at what periods in development this applies. These results point to a need for clinicians to investigate sleep difficulties and treat impaired sleep in paediatric patients with atopic disease.

Apigenin inhibits TGF-β1 induced fibroblast-to-myofibroblast transition in human lung fibroblast populations

BACKGROUND

Flavonoids are dietary plant compounds suspected to reduce the incidence of chronic diseases in several regions of the world. Due to anti-allergic and anti-inflammatory activities, apigenin (4',5,7,-trihydroxyflavone) is thought to interfere with crucial events in the pathomechanism of asthma. However, the effect of apigenin on TGF-β-induced fibroblast-to-myofibroblast transition (FMT) in human lung fibroblast populations, a key event in asthma progression, has not yet been addressed.

METHODS

Primary human bronchial fibroblasts (HBFs) propagated from ex vivo bronchial biopsies derived from patients with diagnosed asthma and human embryonic lung IMR-90 fibroblasts were cultured in vitro and treated with TGF-β1 and apigenin. The myofibroblast fraction in fibroblast populations was evaluated by immunocytochemistry. Expression of α-smooth muscle actin (α-SMA) and tenascin C were assessed at the mRNA and protein level by real-time RT-PCR and immunoblotting, respectively. Additionally, proliferation and viability tests and time lapse-monitoring of movement of individual HBFs and IMR-90 cells were evaluated.

RESULTS

We show that apigenin attenuates TGF-β1-induced FMT in cultures of HBFs, and the magnitude of this attenuation was found to be similar to that observed in the established cell line of lung IMR-90 fibroblasts. Notably, FMT inhibition was observed at low (≈10 μM), non-cytotoxic and non-cytostatic apigenin concentrations and could be correlated with the inhibition of α-SMA and tenascin C expression in HBFs at the mRNA level.

CONCLUSIONS

Our data are the first to demonstrate that apigenin inhibits the TGF-β1-induced expansion of hyper-contractile, α-smooth muscle actin - positive myofibroblasts within populations of HBFs derived from asthmatic patients. They also indicate the possible interference of apigenin with bronchial wall remodeling during the asthmatic process in vivo.

Nonhuman targets in allergic lung conditions

Existing therapies for allergic asthma are far from perfect: the global prevalence of disease increases despite them and they are poorly effective in dealing with the exacerbations that account for hospitalization and asthma deaths. Commercially, there are pressures on these existing medicines too--a growing threat from generics and reluctance by payers to reimburse for increasingly marginal improvements in medicines with precedented mechanisms. Experience shows that attempts to devise selective small-molecule interventions directed at the myriad of downstream effector pathways has not been a fertile ground for the development of effective new medicines. An alternative strategy, exploiting breakthroughs in understanding the molecular basis of allergenicity and the key role of innate immune mechanisms in asthma, is to direct new approaches to the disease triggers themselves: allergens. This raises interesting possibilities for anti-Lipinski drug design (extracellular nonhuman targets, inhaled delivery) and creates unprecedented pharmacological opportunities in the therapeutic area.

Sex differences in the relationship between asthma and overweight in Dutch children: a survey study

Objective

Obesity has been identified as a risk factor for asthma in children. However, in the Netherlands, the obesity prevalence is rising while the asthma prevalence in children is stabilising. The aim of this study is to clarify the association between asthma and Body Mass Index (BMI) in children and whether this association is influenced by sex.

Study Design

Parents of 39,316 children (6-16 years) in the south of the Netherlands were invited to complete an online questionnaire on respiratory symptoms, anthropometric variables and several potential confounding factors for asthma and obesity (including sex, birth weight and breastfeeding). Data was analysed by multivariable logistic regression models and an ordinal regression model.

Results

The response rate was 24% (n boys= 4,743, n girls= 4,529). The prevalence of asthma, overweight and obesity was 8%, 15% and 2% respectively. Body mass index - standard deviation Score (BMI-SDS) was related to current asthma (adjusted OR: 1.29; 95%CI: 1.14-1.45, p≤0.001). When stratified for sex, asthma and BMI-SDS were only related in girls (Girls: adjusted OR: 1.31; 95%CI: 1.13-1.51, p≤0.001. Boys: adjusted OR: 1.01; 95%CI: 0.91-1.14, p=0.72).

Conclusions

The positive association between BMI-SDS and asthma is only present in girls, not boys. Future studies into obesity and asthma should correct for sex in their analyses.

Asthma and severity of the 2009 novel H1N1 influenza: a case-control study

OBJECTIVE

Previous studies reported that the most common chronic condition found among hospitalized patients due to the novel 2009 H1N1 influenza was asthma. However, these studies did not include a concurrent control group. Thus, we investigated the association of asthma status and severity of H1N1 influenza in adults.

METHODS

The study was designed as a multi-site case-control study. Cases were patients who had positive PCR for H1N1 influenza and were admitted to the ICU or general ward with a diagnosis of H1N1 influenza from 1 January 2009 to 31 December 2009. Controls were patients who had positive PCR for H1N1 influenza, but were not admitted to hospitals.

RESULTS

There were 91 H1N1 cases admitted to either ICU (n = 41) or general hospital ward (n = 50), and 56 controls who met the matching criteria were available. Of the 91 cases, the mean age was 47.3 years, 59% were female, and 38% had comorbid conditions. Of the 91 cases, 12 (13%) had asthma. Stratified analysis by comorbid conditions showed that among those without any comorbid conditions, 8 of 56 cases (14%) and 2 of 49 controls (4%) had asthma, (OR: 3.92, 95% CI: 0.79-19.42, p = 0.095) whereas, among the 39 subjects with one or more comorbid conditions, one of 7 controls (14%) had asthma and 4 of 35 (11%) cases had asthma (p = 0.83).

CONCLUSIONS

Asthma may be associated with severity of H1N1 influenza among those without any non-asthma comorbid conditions. However, the limited sample size did not allow this study to fully establish statistical significance. We still recommend asthmatics as a priority group for influenza vaccination and treatment.

Balancing efficacy against safety in sublingual immunotherapy with inhalant allergens: what is the best approach?

Over the last 20 years, studies and clinical trials have demonstrated efficacy, safety and cost-effectiveness of sublingual immunotherapy (SLIT) for respiratory allergic diseases. Nevertheless, it seems to be mostly used as a second-line therapeutic option, and adherence to treatment is not always optimal. Selective literature research was done in Medline and PubMed, including guidelines, position papers and Cochrane meta-analyses concerning SLIT in adult patients. The most recent reviews confirm SLIT as viable and efficacious treatment especially for allergic rhinitis, even if the optimal dosage, duration, schedule are not clearly established for most of the products. Despite an optimal safety profile, tolerability and patient-reported outcomes concerning SLIT have received poor attention until now. Recently, new tools have been specifically developed in order to investigate these aspects. Regular assessment of tolerability profile and SLIT-related patient-reported outcomes will allow balancing efficacy with tolerability and all the other patient-related variables that may affect treatment effectiveness beyond its efficacy.

Residential characteristics and household risk factors and respiratory diseases in Chinese women: the Seven Northeast Cities (SNEC) study

BACKGROUND

Few studies have assessed the impact of residential home characteristics and home environmental risk factors on respiratory diseases in Chinese women. Therefore, this study sought to determine the association between residential home features, domestic pets, home renovation and other indoor environmental risk factors with respiratory health outcomes of Chinese women.

METHODS

This cross-sectional study included a study sample of 30,780 Chinese women aged 23 to 49 from 25 districts of seven cities in Liaoning Province, Northeast China. Information on respiratory health, residential characteristics, and indoor air pollution sources was obtained by a standard questionnaire from the American Thoracic Society. Multivariable logistic regression was used to estimate prevalence odds ratios (POR) and 95% confidence interval (95%CI).

RESULTS

The odds of respiratory diseases were higher for those who lived near the main road, or near ambient air pollution sources. Pet-keeping was associated with increased odds of chronic bronchitis (POR=1.40; 95%CI: 1.09-1.81) and doctor-diagnosed asthma (POR=2.07; 95%CI: 1.18-3.64). Additionally, humidifier use was associated with increased odds of chronic bronchitis (POR=1.44; 95%CI: 1.07-1.94). Home renovation in recent 2 years was associated with increased likelihood of allergic rhinitis (POR=1.39; 95%CI 1.17-1.64).

CONCLUSION

Home renovation and residential home environmental risk factors were associated with an increased likelihood of respiratory morbidity among Chinese women.

Increase in prevalence of physician-diagnosed asthma in Helsinki during the Finnish Asthma Programme: improved recognition of asthma in primary care? A cross-sectional cohort study

Background:

The continuing rise in asthma prevalence has been questioned, with recent reports suggesting a plateau.

Aims:

To assess a 10-year trend in the age-adjusted prevalence of physician-diagnosed asthma, respiratory and allergic symptoms, and use of asthma medication in the adult population of Helsinki during the Finnish Asthma Programme from 1994 to 2004.

Methods:

Two cross-sectional postal surveys were conducted among random Finnish National Population Registry samples 10 years apart using the same protocol. A total of 6,062 subjects (75.9%) and 2,449 subjects (61.9%) participated in 1996 and 2006, respectively.

Results:

The prevalence of physician-diagnosed asthma increased from 6.5% in 1996 to 10.0% in 2006 (p<0.001). This was evident in both genders aged <60 years, but particularly in women aged <40 years, paralleling an increased use of asthma medication. Concurrently, the prevalence of allergic rhinoconjunctivitis increased from 37.2% to 44.4% (p<0.001). The prevalence of physician-diagnosed chronic obstructive pulmonary disease remained unchanged (3.7%), while current smoking abated. Subjects with a smoking history had more respiratory symptoms (p<0.001). Among subjects without physician-diagnosed asthma, those reporting allergic rhinoconjunctivitis had a higher prevalence of lower respiratory tract symptoms.

Conclusions:

The prevalence of allergic rhinoconjunctivitis and physician-diagnosed asthma has increased in Helsinki during 10 years in adults, especially in women aged <40 years. Concomitantly, the use of asthma medication increased and subjects with physiciandiagnosed asthma were less symptomatic. The increase in the prevalence of physician-diagnosed asthma may partly be due to improved diagnostic recognition of asthma in primary care during the Finnish Asthma Programme, but the concurrent rise in allergic rhinoconjunctivitis may reflect a true rise in prevalence.

Ten years of asthma admissions to adult critical care units in England and Wales

OBJECTIVES

To describe the patient demographics, outcomes and trends of admissions with acute severe asthma admitted to adult critical care units in England and Wales.

DESIGN

10-year, retrospective analysis of a national audit database.

SETTING

Secondary care: adult, general critical care units in the UK.

PARTICIPANTS

830 808 admissions to adult, general critical care units.

PRIMARY AND SECONDARY OUTCOME MEASURES

Demographic data including age and sex, whether the patient was invasively ventilated or not, length of stay (LOS; both in the critical care unit and acute hospital), survival (both critical care unit and acute hospital) and time trends across the 10-year period.

RESULTS

Over the 10-year period, there were 11 948 (1.4% of total) admissions with asthma to adult critical care units in England and Wales. Among them 67.5% were female and 32.5% were male (RR F:M 2.1; 95% CI 2.0 to 2.1). Median LOS in the critical care unit was 1.8 days (IQR 0.9-3.8). Median LOS in the acute hospital was 7 days (IQR 4-14). Critical care unit survival rate was 95.5%. Survival at discharge from hospital was 93.3%. There was an increase in admissions to adult critical care units by an average of 4.7% (95% CI 2.8 to 6.7)/year.

CONCLUSIONS

Acute asthma represents a modest burden of work for adult critical care units in England and Wales. Demographic patterns for admission to critical care unit mirror those of severe asthma in the general adult community. The number of critical care admissions with asthma are rising, although we were unable to discern whether this represents a true increase in the incidence of acute asthma or asthma severity.

Goal-setting intervention in patients with active asthma: protocol for a pilot cluster-randomised controlled trial

BACKGROUND

Supporting self-management behaviours is recommended guidance for people with asthma. Preliminary work suggests that a brief, intensive, patient-centred intervention may be successful in supporting people with asthma to participate in life roles and activities they value. We seek to assess the feasibility of undertaking a cluster-randomised controlled trial (cRCT) of a brief, goal-setting intervention delivered in the context of an asthma review consultation.

METHODS/DESIGN

A two armed, single-blinded, multi-centre, cluster-randomised controlled feasibility trial will be conducted in UK primary care. Randomisation will take place at the practice level. We aim to recruit a total of 80 primary care patients with active asthma from at least eight practices across two health boards in Scotland (10 patients per practice resulting in ~40 in each arm). Patients in the intervention arm will be asked to complete a novel goal-setting tool immediately prior to an asthma review consultation. This will be used to underpin a focussed discussion about their goals during the asthma review. A tailored management plan will then be negotiated to facilitate achieving their prioritised goals. Patients in the control arm will receive a usual care guideline-based review of asthma. Data on quality of life, asthma control and patient confidence will be collected from both arms at baseline and 3 and 6 months post-intervention. Data on health services resource use will be collected from all patient records 6 months pre- and post-intervention. Semi-structured interviews will be carried out with healthcare staff and a purposive sample of patients to elicit their views and experiences of the trial. The outcomes of interest in this feasibility trial are the ability to recruit patients and healthcare staff, the optimal method of delivering the intervention within routine clinical practice, and acceptability and perceived utility of the intervention among patients and staff.

TRIAL REGISTRATION

ISRCTN18912042.

Socioeconomic status and the quality of prescribing asthma drugs in Sweden

INTRODUCTION

Socioeconomic status (SES) is strongly associated with morbidity as well as with health care utilization and expenditure. The association between SES and quality of prescribing of asthma drugs is less studied.

OBJECTIVES

The aim of this study was to examine the association between socioeconomic factors, i.e. education, income and country of birth, and the prevalence, incidence and adherence to guidelines for antiasthmatic drugs.

METHODS

This registry study includes all Swedish citizens aged 25-44 years who redeemed at least one prescription of an antiasthmatic drug during 2010. Incidence and prevalence was calculated. The adherence to guidelines was studied using two defined quality indicators. Heavy users were also assessed.

RESULTS

Incidence for antiasthmatic drugs was 18.4 per 1000 person-years and the prevalence 50.9 per 1000 inhabitants. Previously untreated patients who redeemed fixed combination ranged from 45% to 49%. Patients who purchase long-acting beta-2-adrenoceptor agonists (LABA) without inhaled corticosteroid ranged from 43% to 59%. Six percent of the population was classified as heavy users.

CONCLUSION

The study showed a high incidence and prevalence of asthma drug use with a poor adherence to guidelines for rational drug prescribing. Fixed combination as first line asthma treatment as well as purchasing LABA without concomitant ICS was more common in patients born outside Scandinavia. Heavy users of short-acting bronchodilators were associated with male sex, high age, low income levels and low levels of education.

Prevalence and sensitization of atopic allergy and coeliac disease in the Northern Sweden Population Health Study

Background

Atopic allergy is effected by a number of environmental exposures, such as dry air and time spent outdoors, but there are few estimates of the prevalence in populations from sub-arctic areas.

Objective

To determine the prevalence and severity of symptoms of food, inhalation and skin-related allergens and coeliac disease (CD) in the sub-arctic region of Sweden. To study the correlation between self-reported allergy and allergy test results. To estimate the heritability of these estimates.

Study design

The study was conducted in Karesuando and Soppero in Northern Sweden as part of the Northern Sweden Population Health Study (n=1,068). We used a questionnaire for self-reported allergy and CD status and measured inhalation-related allergens using Phadiatop, food-related allergens using the F×5 assay and IgA and IgG antibodies against tissue transglutaminase (anti-tTG) to indicate prevalence of CD.

Results

The prevalence of self-reported allergy was very high, with 42.3% reporting mild to severe allergy. Inhalation-related allergy was reported in 26.7%, food-related allergy in 24.9% and skin-related allergy in 2.4% of the participants. Of inhalation-related allergy, 11.0% reported reactions against fur and 14.6% against pollen/grass. Among food-related reactions, 14.9% reported milk (protein and lactose) as the cause. The IgE measurements showed that 18.4% had elevated values for inhalation allergens and 11.7% for food allergens. Self-reported allergies and symptoms were positively correlated (p<0.01) with age- and sex-corrected inhalation allergens. Allergy prevalence was inversely correlated with age and number of hours spent outdoors. High levels of IgA and IgG anti-tTG antibodies, CD-related allergens, were found in 1.4 and 0.6% of participants, respectively. All allergens were found to be significantly (p<3 e–10) heritable, with estimated heritabilities ranging from 0.34 (F×5) to 0.65 (IgA).

Conclusions

Self-reported allergy correlated well with the antibody measurements. The prevalence of allergy was highest in the young and those working inside. Heritability of atopy and sensitization was high. The prevalence of CD-related autoantibodies was high and did not coincide with the self-reported allergy.

Perinatal bisphenol A exposures increase production of pro-inflammatory mediators in bone marrow-derived mast cells of adult mice

Bisphenol A (BPA) is a widely used monomer of polycarbonate plastics and epoxide resin that has been implicated in asthma pathogenesis when exposure occurs to the developing fetus. However, few studies have examined the relationship between perinatal BPA exposure and asthma pathogenesis in adulthood. This study used an isogenic mouse model to examine the influence of perinatal BPA exposure via maternal diet on inflammatory mediators associated with asthma in 6-month-old adult offspring by measuring bone marrow-derived mast cell (BMMC) production of lipid mediators (cysteinyl leukotrienes and prostaglandin D2), cytokines (interleukin [IL]-4, IL-5, IL-6, IL-13, and tumor necrosis factor [TNF]-α), and histamine. Global DNA methylation levels in BMMCs from adult offspring were determined to elucidate a potential regulatory mechanism linking perinatal exposure to mast cell phenotype later in life. Four BPA exposure doses were tested: low (50 ng BPA/kg diet, n = 5), medium (50 μg BPA/kg diet, n = 4), high (50 mg BPA/kg diet, n = 4), and control (n = 3). Following BMMC activation, increases in cysteinyl leukotriene (p < 0.01) and TNFα (p < 0.05) production were observed in all BPA-exposure groups, and increases in prostaglandin D2 (p < 0.01) and IL-13 (p < 0.01) production were observed in the high exposure group. Additionally, BMMCs from adult mice in all exposure groups displayed a decrease in global DNA methylation compared to control animals. Thus, perinatal BPA exposure displayed a long-term influence on mast cell-mediated production of pro-inflammatory mediators associated with asthma and global DNA methylation levels, suggesting a potential for mast cell dysregulation, which could affect pulmonary inflammation associated with allergic airway disease into adulthood.

High prevalence of diagnosis of diabetes, depression, anxiety, hypertension, asthma and COPD in the total population of Stockholm, Sweden - a challenge for public health

Background

There is limited knowledge on the prevalence of disease in total populations. Such studies have historically been difficult to conduct but the development of health data registers has facilitated large-scale studies on recorded diagnoses in entire regions. The aim of this study was to analyze the prevalence of diagnosis of six common diseases in the Swedish capital region.

Methods

The study population included all living persons who resided in Stockholm County, Sweden, on December 31^st 2011 (N = 2 093 717). Information on all consultations between 2007 and 2011 was obtained from primary health care, specialist outpatient care and inpatient care. Prevalence was defined as the proportion of individuals with a recorded diagnosis of diabetes, depression, anxiety disorders, hypertension, asthma and chronic obstructive pulmonary disease during the five year period, respectively. Analyses were done by age and gender.

Results

Hypertension had the highest five-year prevalence (12.2%), followed by depression (6.6%), diabetes mellitus (6.2%), asthma (5.9%), anxiety disorders/phobia (4.8%), and COPD (1.8%). Diabetes was more common in men (5.3% of women and 7.1% of men) while depression (8.7% in women and 4.4% in men) and anxiety (6.3% in women and 3.4% in men) were considerably more common in women. Smaller gender differences were also found for hypertension (13.0% in women and 11.4% in men), asthma (6.4% in women and 5.4% in men) and COPD (2.1% in women and 1.6% in men). Diabetes, hypertension and COPD increased markedly with age, whereas anxiety, depression and asthma were fairly constant in individuals above 18 years. During one year of observation, more than half of all patients had only been diagnosed in primary health care, with hypertension being the diagnosis with the largest proportion of patients only identified in primary health care (70.6%).

Conclusion

The prevalence of common diseases in the population can be estimated by combining data gathered during consecutive years from primary care, specialist outpatient care and inpatient care. However, accuracy of disease prevalence is highly dependent on the quality of the data. The high prevalence of the six diagnoses analysed in this study calls for preventive action to minimize suffering and costs to society.

Preventative effect of an herbal preparation (HemoHIM) on development of airway inflammation in mice via modulation of Th1/2 cells differentiation

HemoHIM, an herbal preparation of three edible herbs (Angelica gigas Nakai, Cnidium officinale Makino, Paeonia japonica Miyabe) is known to increase the Th1 immune response as well as reduce the allergic response in human mast cells. Here, our goal was to determine whether or not HemoHIM could induce Th1 cell differentiation as well as inhibit the development of airway inflammation. To study Th1/Th2 cell differentiation, naive CD4⁺ T cells isolated from C57BL/6 mouse spleens were cultured with or without HemoHIM. To examine airway inflammation, C57BL/6 mice were fed HemoHIM for 4 weeks before sensitization and provocation with ovalbumin (OVA). In an in vitro experiment, naive CD4⁺ T cells displayed increased Th1 (IFN-γ⁺ cell) as well as decreased Th2 (IL-4⁺ cell) differentiation in a HemoHIM concentration-dependent manner. Furthermore, in an airway inflammation mice model, eosinophil numbers in BALF, serum levels of OVA-specific IgE and IgG1, and cytokine (IL-4, IL-5, and IL-13) levels in BALF and the supernatant of splenocytes all decreased upon HemoHIM (100 mg/kg body weight) pretreatment (4 weeks). These results show that HemoHIM attenuated allergic airway inflammation in the mouse model through regulation of the Th1/Th2 balance.

Rising trends in the prevalence of asthma and allergic diseases among school children in the north-west coastal part of Croatia

OBJECTIVE

To estimate time trends in prevalence of symptoms and reported diagnosis related to asthma, allergic rhinitis/conjunctivitis and eczema among school children in the north-west coastal part of Croatia.

METHODS

Results of two identical cross-sectional surveys conducted on the same area 8 years apart (school years 2001/02 versus 2009/10) in complete adherence to the protocol of the International Study of Asthma and Allergies in Childhood were compared. Surveyed population comprised two age groups: 6-7 years (n = 1634 versus n = 1052) and 13-14 years (n = 2194 versus 1181).

RESULTS

Significant (p < 0.001) increases in prevalence (%) of symptoms related to asthma (8.4 versus 14.0), allergic rhinitis (17.5 versus 25.6), allergic rhinoconjunctivitis (6.7 versus 15.3) and eczema (3.4 versus 5.9) were observed in the 13-14-year-olds. In the 6-7-year-olds there were observed significant (p < 0.001) increases in prevalence of symptoms of eczema (5.4 versus 8.7) and allergic rhinitis (16.9 versus 22.1) whereas prevalence of symptoms related to asthma (9.7 versus 9.4; p = 0.398) and allergic rhinoconjunctivitis (5.6 versus 6.8; p = 0.102) showed to be stable. Significant increases in prevalence of reported diagnosis were observed for asthma (5.2 versus 6.9; p = 0.02) and hay fever (10.5 versus 14.6; p < 0.001) in the older, and for eczema (10.6 versus 14.1; p < 0.001) in the younger age group.

CONCLUSION

Prevalence of asthma and allergic diseases among the school children living on the surveyed area showed a rising trend.

Bisphenol A at concentrations relevant to human exposure enhances histamine and cysteinyl leukotriene release from bone marrow-derived mast cells

Bisphenol A (BPA), a monomer of polycarbonate plastics and epoxide resin, acts as an endocrine-active compound and has been shown to enhance the inflammatory response to allergen challenge. Previous reports in rodents have demonstrated that perinatal BPA exposure alters airway inflammation following sensitization and challenge to ovalbumin in juvenile and adult offspring. Additionally, a high concentration of BPA has been shown to enhance mediator release in mast cell lines. This study aimed to determine if short-term BPA exposure, at levels relevant to human exposure, enhances mast cell release of histamine and cysteinyl leukotrienes (CysLTs). Primary murine bone marrow-derived mast cells (BMMC) produced from the femurs of female C57BL/6 mice were stimulated with BPA or estradiol (E2) in vitro. It was observed that both BPA and E2 increased BMMC histamine release over a range of nanomolar concentrations (1-1000 nM). The estrogen receptor (ER) antagonist ICI 182,780 partially blocked the ability of E2, but not BPA, to elevate histamine release. BPA also increased CysLT release, which was not abrogated by ER inhibition. It was also observed that the ability of BPA to enhance histamine and CysLT release was inhibited by blocking the extracellular signal-regulated kinase (ERK) pathway with U0126 or by chelating extracellular calcium (Ca(2+)) using EGTA. In summary, these experiments are the first to demonstrate that acute BPA exposure enhances mast cell histamine and CysLT release in vitro--an effect that is not dependent on an ER-mediated mechanism. Instead, BPA-induced mast cell histamine and CysLT release may be mediated, in part, by the ERK pathway and extracellular Ca(2+) concentrations. These data suggest that exposure to BPA at levels relevant to human exposure may provoke an acute inflammatory response in atopic individuals via enhanced mast cell activation.

Update on anticytokine treatment for asthma

Current advances in the knowledge of asthma pathobiology suggest that anticytokine therapies can be potentially useful for the treatment of this complex and heterogeneous airway disease. Recent evidence is accumulating in support of the efficacy of anti-IL-4, anti-IL-5, and anti-IL-13 drugs. Therefore, these new developments are now changing the global scenario of antiasthma therapies, especially with regard to more severe disease. Current findings referring to variability of individual therapeutic responses highlight that the different asthma subtypes need to be well characterized, in order to implement phenotype-targeted treatments which in the near future will hopefully be mainly based on cytokine-directed biologics.

Investigating the effectiveness of the Mediterranean diet in pregnant women for the primary prevention of asthma and allergy in high-risk infants: protocol for a pilot randomised controlled trial

BACKGROUND

Over recent decades there has been a substantial increase in asthma and allergic disease especially in children. Given the high prevalence, and the associated high disease burden and costs, there is a need to identify effective strategies for the primary prevention of asthma and allergy. A recent systematic review of the literature found strong supportive epidemiological evidence for a protective role of the Mediterranean diet, which now needs to be confirmed through formal experimental studies. This pilot trial in pregnant women aims to establish recruitment, retention and acceptability of a dietary intervention, and to assess the likely impact of the intervention on adherence to a Mediterranean diet during pregnancy.

METHODS/DESIGN

This study was a pilot, two-arm, randomised controlled trial in a sample population of pregnant women at high risk of having a child who will develop asthma or allergic disease.

DISCUSSION

The work ultimately aims to contribute to improving health outcomes through seeking to reduce the incidence of asthma and allergic problems. This pilot trial will prove invaluable in informing the subsequent planned large-scale, parallel group, randomised controlled trial.

Galangin Abrogates Ovalbumin-Induced Airway Inflammation via Negative Regulation of NF-κB

Persistent activation of nuclear factor κB (NF-κB) has been associated with the development of asthma. Galangin, the active pharmacological ingredient from Alpinia galanga, is reported to have a variety of anti-inflammatory properties in vitro via negative regulation of NF-κB. This study aimed to investigate whether galangin can abrogate ovalbumin- (OVA-) induced airway inflammation by negative regulation of NF-κB. BALB/c mice sensitized and challenged with OVA developed airway hyperresponsiveness (AHR) and inflammation. Galangin dose dependently inhibited OVA-induced increases in total cell counts, eosinophil counts, and interleukin-(IL-) 4, IL-5, and IL-13 levels in bronchoalveolar lavage fluid, and reduced serum level of OVA-specific IgE. Galangin also attenuated AHR, reduced eosinophil infiltration and goblet cell hyperplasia, and reduced expression of inducible nitric oxide synthase and vascular cell adhesion protein-1 (VCAM-1) levels in lung tissue. Additionally, galangin blocked inhibitor of κB degradation, phosphorylation of the p65 subunit of NF-κB, and p65 nuclear translocation from lung tissues of OVA-sensitized mice. Similarly, in normal human airway smooth muscle cells, galangin blocked tumor necrosis factor-α induced p65 nuclear translocation and expression of monocyte chemoattractant protein-1, eotaxin, CXCL10, and VCAM-1. These results suggest that galangin can attenuate ovalbumin-induced airway inflammation by inhibiting the NF-κB pathway.

Multifactorial intervention for children with asthma and overweight (Mikado): study design of a randomised controlled trial

Background

In children, the prevalence’s of both obesity and asthma are disconcertingly high. Asthmatic children with obesity are characterised by less asthma control and a high need for asthma medication. As the obese asthmatic child is becoming more common in the clinical setting and the disease burden of the asthma-obesity phenotype is high, there is an increasing need for effective treatment in these children. In adults, weight reduction resulted in improved lung function, better asthma control and less need for asthma medication. In children this is hardly studied. The Mikado study aims to evaluate the effectiveness of a long term multifactorial weight reduction intervention, on asthma characteristics in children with asthma and a high body weight.

Methods/design

The Mikado study is a two-armed, randomised controlled trial. In total, 104 participants will be recruited via online questionnaires, pulmonary paediatricians, the youth department of the Municipal Health Services and cohorts of existing studies. All participants will be aged 6–16 years, will have current asthma, a Body Mass Index in the overweight or obesity range, and no serious comorbidities (such as diabetes, heart diseases). Participants in the intervention arm will receive a multifactorial intervention of 18 months consisting of sessions concerning sports, parental involvement, individual counselling and lifestyle advices including dietary advices and cognitive behavioural therapy. The control group will receive usual care. The primary outcome variables will include Forced Expiratory Volume in one second and Body Mass Index - Standard Deviation Score. Secondary outcomes will include other lung function parameters (including dynamic and static lung function parameters), asthma control, asthma-specific quality of life, use of asthma medication and markers of systemic inflammation and airway inflammation.

Discussion

In this randomised controlled trial we will study the potential of a multifactorial weight reduction intervention to improve asthma-related outcome measures in asthmatic children with overweight. Moreover, it will provide information about the underlying mechanisms in the relationship between asthma and a high body weight in children. These findings can contribute to optimal management programs and better clinical guidelines for children with asthma and overweight.

Trial registration

Clinicaltrial.gov NCT00998413

Characteristics of children with asthma who achieved remission of asthma

OBJECTIVE

To characterize two groups of asthmatics who had achieved remission and those who had not achieved remission of asthma.

METHODS

The study was a retrospective cohort study based on 117 asthmatic children who participated in a previous study. We categorized the children into two groups: asthmatics with remission versus asthmatics without remission. We defined remission of asthma as lack of symptoms/signs of asthma or asthma-related medications or health care services for at least three consecutive years. Long-term remission was defined by no relapse of asthma after achieving remission. We characterized these groups.

RESULTS

Of the 117 subjects, 70 (60%) were male, 91 (78%) were Caucasians, and the mean age at index date of asthma was 8.1 years. A total of 59 asthmatic children (50%) achieved remission and 28 asthmatics (24%) achieved long-term remission. Asthmatics with remission were more likely to be Caucasian (87%) compared to those without (69%) (p = .039) There were no differences in the frequency of visits for viral (0.3 vs. 0.4 per person-years, p = .29) or bacterial infections (0.7 vs. 0.5 per person-years, p = .49) between asthmatics with and without remission. Gender, socioeconomic status, smoking exposure, family history of asthma or atopy, breastfeeding history, peak flow meter availability, asthma action plan, and influenza vaccinations were not associated with remission.

CONCLUSIONS

Only half of asthmatic children accomplished remission of asthma ever and 24% of asthmatic children had long-term remission. Ethnicity may affect remission of asthma but microbial infections may not influence the likelihood of remission of asthma and vice versa.

Cytotoxic T lymphocyte antigen 4-immunoglobulin G is a potent adjuvant for experimental allergen immunotherapy

Allergen-specific immunotherapy (SIT) is the only treatment for allergic diseases that targets allergen-specific T helper type 2 (Th2) cells, which are the cause of the disease. There is an unmet requirement for adjuvants that increase the clinical efficacy of SIT allowing application of lower doses of the allergen, thereby reducing the risk of anaphylactic reactions. Cytotoxic T lymphocyte antigen 4-immunoglobulin (CTLA-4-Ig) has been shown to induce immunological tolerance in autoimmunity and allograft transplantation by blocking T cell co-stimulation and induction of the immunoregulatory enzyme indoleamine 2,3 dioxygenase (IDO). Previously, we showed that CTLA-4-Ig treatment at the time of allergen inhalation induced tolerance to subsequent allergen exposure in a mouse model of asthma. In this study, we test the hypothesis that CTLA-4-Ig acts as an adjuvant for experimental SIT. We evaluated the adjuvant effects of CTLA-4-Ig on SIT in a mouse model of ovalbumin-driven asthma. We used both wild-type and IDO-deficient mice to assess the role of IDO in the adjuvant effects of CTLA-4-Ig. Co-administration of CTLA-4-Ig strongly increased SIT-induced suppression of airway hyperreactivity (AHR), specific IgE in serum, airway eosinophilia and Th2 cytokine levels. Moreover, we found that CTLA-4-Ig, as an adjuvant for SIT, is equally effective in IDO-deficient and wild-type mice, demonstrating that the effect of CTLA-4-Ig is independent of IDO expression. We show that CTLA-4-Ig acts as a potent adjuvant to augment the therapeutic effects of SIT. As the adjuvant activity of CTLA-4-Ig is independent of IDO, we conclude that it acts by blocking CD28-mediated T cell co-stimulation.

Is asthma a vanishing disease? A study to forecast the burden of asthma in 2022

Background

Recent evidence regarding temporal trends of asthma burden has not been consistent, with some countries reporting decreases in prevalence of asthma. In Ontario, the province in Canada with the highest population, the prevalence of asthma rose at a rate of 0.5% per year between 1996 and 2005. These estimates were based on population-based health services use data spanning more than a decade and provide a powerful source to forecast the trends of asthma burden. The objective of this study was to use observed population trends data of asthma incidence and prevalence to forecast future disease burden.

Methods

The Ontario Asthma Surveillance Information System (OASIS) used health administrative databases to identify and track all individuals in the province with asthma. Individuals with asthma identified between April 1, 1996 and March 31, 2010 were included. Exponential smoothing models were applied to annual data to project incidence to the year 2022, prevalence was estimated by applying the cumulative projected incidence to the projected population.

Results

While asthma incidence is falling, the absolute number of prevalent cases will continue to rise. We projected that almost 1 in 8 individuals in Ontario will have asthma by the year 2022, suggesting that asthma will continue to be a major burden on individuals and the health care system.

Conclusions

These projections will help inform health care planners and decision-makers regarding resource allocation to optimize asthma outcomes.

Dietary Patterns and Wheezing in the Midst of Nutritional Transition: A Study in Brazil

To assess the influence of dietary patterns on the prevalence of wheezing in the child and adolescent population in Northeastern Brazil. This is a cross-sectional study of male and female students, 6-12 years old, from the public elementary schools of São Francisco do Conde, Bahia, Northeastern Brazil. The report of wheezing in the past 12 months was collected using a questionnaire from the International Study of Asthma and Allergies in Childhood Program phase III, adapted to Portuguese. Consumption patterns were derived from principal component analysis based on the frequency of consumption of 97 food items by the food frequency questionnaire. We also obtained the anthropometric status, level of physical activity, pubertal development, and socioeconomic information, for each participant. Multivariate logistic regression analyses were used to assess the associations of interest. Of the children surveyed, 10.6% reported having wheezing. We identified 2 dietary patterns named Western and Prudent. We found a positive statistically significant association of the Western pattern with wheeze (odds ratio=1.77, 95% confidence interval: 1.10-2.84) after adjustment for total energy intake and controlling for potential confounders. The results showed that the Western dietary pattern was associated with wheezing. Our result is according with previous findings reported in several other studies.

Lovastatin-induced decrease of intracellular cholesterol level attenuates fibroblast-to-myofibroblast transition in bronchial fibroblasts derived from asthmatic patients

Chronic inflammation of the airways and structural changes in the bronchial wall are basic hallmarks of asthma. Human bronchial fibroblasts derived from patients with diagnosed asthma display in vitro predestination towards TGF-β-induced fibroblast-to-myofibroblast transition (FMT), a key event in the bronchial wall remodelling. Statins inhibit 3-hydroxymethyl-3-glutaryl coenzyme A reductase, a key enzyme in the cholesterol synthesis pathway and are widely used as antilipidemic drugs. The pleiotropic anti-inflammatory effects of statins, independent of their cholesterol-lowering capacity, are also well established. Since commonly used anti-asthmatic drugs do not reverse the structural remodelling of the airways and statins have tentative anti-asthmatic activity, we have studied the effect of lovastatin on FMT in populations of human bronchial fibroblasts derived from asthmatic patients. We demonstrate that the intensity of FMT induced by TGF-β1 was strongly and dose-dependently attenuated by lovastatin. Furthermore, we show that neither the suppression of prenylation of signalling proteins nor the effect on reactive oxygen species formation are important for lovastatin-induced inhibition of myofibroblast differentiation. On the other hand, we show that a squalene synthase inhibitor, zaragozic acid A, reduced the TGF-β1-induced FMT to an extent comparable to lovastatin effect. Additionally we demonstrate that in bronchial fibroblast populations, both inhibitors (lovastatin and zaragozic acid A) attenuate the TGF-β1-induced Smad2 nuclear translocation in a manner dependent on intracellular cholesterol level. Our data suggest that statins can directly, by decrease of intracellular cholesterol level, affect basic cell signalling events crucial for asthmatic processes and potentially prevent perilous bronchial wall remodelling associated with intensive myofibroblast formation.

Asthma and the risk of type 2 diabetes in the Singapore Chinese Health Study

AIM

Asthma is believed to increase the risk for several proinflammatory diseases, yet epidemiologic studies on asthma in relation to risk of developing type 2 diabetes are sparse and have reported inconsistent results. In the present study, we investigated the hypothesis that asthma is associated with an increased risk of incident type 2 diabetes in Chinese adults.

METHODS

We used data from the Singapore Chinese Health Study, including Chinese men and women aged 45-74 years, free of cancer, heart disease, stroke, and diabetes at baseline (1993-1998) and followed through 2004 for incident physician-diagnosed diabetes. Cox regression models were used to examine the associations between self-reported history of physician-diagnosed asthma and risk of diabetes.

RESULTS

During an average follow-up of 5.7 years per person, 2234 of the 42,842 participants included in the current analyses reported diagnoses of type 2 diabetes. After adjustment for potential confounders, not including body mass index (BMI), asthma was associated with a 31% increased risk of incident diabetes (HR=1.31; 95% CI: 1.00-1.72). The association was attenuated after adjustment for adult BMI (HR=1.25; 95% CI: 0.95-1.64). The asthma-diabetes association appeared stronger for adult- vs. child-diagnosed asthma cases, and for participants who were obese compared to non-obese.

CONCLUSIONS

In Singaporean Chinese adults we observed a positive association between self-reported, physician-diagnosed asthma and risk of developing type 2 diabetes that was modestly attenuated by adjustment for BMI.

Epidemiology of asthma in the United States

Incidence and prevalence rates of asthma can vary greatly according to population and location. The National Heart and Blood Institute of the National Institutes of Health defines asthma as a common chronic disorder of the airways that involves a complex interaction of airflow obstruction, bronchial hyperresponsiveness, and an underlying inflammation. This article uses the most common definitions and diagnostic methods for asthma. In 2009 there were 2.1 million asthma-related emergency department (ED) visits. ED visits lend an opportunity for providers to identify and intervene in the care of patients whose asthma is poorly controlled.

Asthma and rhinitis: what is the relationship?

PURPOSE OF REVIEW

Asthma and rhinitis are commonly associated and they influence their respective control. New observations have contributed to better understand how to assess those conditions and how they influence each other.

RECENT FINDINGS

Recent studies found that not only the intensity, but also the duration of rhinitis could be correlated with the development of asthma and possibly its remission. The measure of exhaled nitric oxide (FeNO) has been used to show the presence of lower airway inflammation in rhinitic patients, with or without asthma. Furthermore, it has been shown that allergic rhinitis could affect asthma control in children as in adults, and consequently suggested that allergic rhinitis and asthma should be concomitantly approached in regard to their diagnosis and treatment. Additional observations showed improvements in various asthma outcomes with the treatment of rhinitis.

SUMMARY

These new data confirm the strong link between asthma and rhinitis, the importance of their interactions, and the need to identify and treat rhinitis adequately in asthmatic patients.

Increasing prevalence of asthma, allergic rhinoconjunctivitis and eczema among schoolchildren: three surveys during the period 1985-2008

AIM

The prevalence of asthma, allergic rhinoconjunctivitis (AR) and eczema among children has increased worldwide in the last four decades, but recent studies disagree as to whether the prevalence is continuing to rise or is levelling off or declining. The aim of this study was to assess time trends in a subarctic population.

METHODS

A cross-sectional, questionnaire-based survey was carried out in 2008 among children aged 7-14 years in randomly selected schools in Nordland County, Norway (n = 4150). The results are compared with results from identical studies in 1985 (n = 4870) and 1995 (n = 4456).

RESULTS

The main findings were an increasing prevalence of asthma ever (7.3% in 1985 to 17.6% in 2008, p for trend < 0.001) and AR ever (15.9% in 1985 to 24.5% in 2008, p for trend < 0.001), while the prevalence of eczema ever, after an increase between 1985 and 1995, remained unchanged in the last time period. The prevalence of current disease doubled and trebled between 1995 and 2008 for all three diseases.

CONCLUSION

A repeated cross-sectional survey between 1985 and 2008 documented an increasing prevalence of asthma ever and AR ever among schoolchildren (7-14 years), together with a considerably increase in current asthma, AR and eczema between 1995 and 2008.

Dehydroxymethylepoxyquinomicin (DHMEQ), a novel NF-kappaB inhibitor, inhibits allergic inflammation and airway remodelling in murine models of asthma

BACKGROUND

Dehydroxymethylepoxyquinomicin (DHMEQ) is a newly developed compound that inhibits nuclear factor κB activation and is reported to ameliorate animal models of various inflammatory diseases without significant adverse effects. Because nuclear factor κB is a transcription factor that plays a critical role in the pathophysiology of asthma, DHMEQ may be of therapeutic benefit in asthma.

OBJECTIVE

The purpose of this study was to evaluate the effects of DHMEQ on airway inflammation and remodelling in murine models of asthma.

METHODS

The BALB/c mice were sensitized and then challenged acutely or chronically with ovalbumin and administered DHMEQ intraperitoneally before each challenge. Inflammation of airways, lung histopathology and airway hyper responsiveness to methacholine challenge were evaluated. In addition, the effect of DHMEQ on production of cytokines and eotaxin-1 by murine splenocytes, human peripheral blood mononuclear cells and bronchial epithelial cells was investigated.

RESULTS

Airway hyper responsiveness was ameliorated in both acutely and chronically challenged models by treatment with DHMEQ. DHMEQ significantly reduced eosinophilic airway inflammation and levels of Th2 cytokines in bronchoalveolar lavage fluid in the acute model. It also inhibited parameters of airway remodelling including mucus production, peribronchial fibrosis and the expression of α-smooth muscle actin. Moreover, the production of Th2 cytokines from murine splenocytes and human peripheral blood mononuclear cells and the production of eotaxin-1 by bronchial epithelial cells were inhibited by DHMEQ.

CONCLUSIONS AND CLINICAL RELEVANCE

These results indicate that DHMEQ inhibits allergic airway inflammation and airway remodelling in murine models of asthma. DHMEQ may have therapeutic potential in the treatment of asthma.

Hair zinc and selenium levels in children with recurrent wheezing

The prevalence of asthma and other allergic diseases has increased markedly in the last few decades. Oxidative stress plays a central role in asthma pathogenesis, and reduced daily consumption of antioxidants is positively correlated with increased risk of asthma. Zinc (Zn) and selenium (Se) are the main antioxidant elements. In our study, we aimed to investigate hair Zn and Se levels in children with recurrent wheezing. The study included 65 patients with recurrent wheezing (RW) and 65 healthy children (HC). The hair Zn and Se levels (µg/g) of the RW group were lower in comparison with the HC group (162.43 ± 91.52 vs. 236.38 ± 126.44, P < 0.001, and 217.37 ± 83.01 vs. 280.53 ± 122.73, P < 0.001, respectively). Total antioxidant capacity (TAC) (mmol/L) of the RW group was found to be significantly lower in comparison with the HC group (1.38 ± 0.14 vs. 1.53 ± 0.20, respectively; P < 0.001). Number of wheezing episodes in the last 6 months were negatively correlated with serum TAC, hair Zn, and Se levels in RW group (r(p)  = -0.291, P = 0.001; r(p)  = -0.209, P = 0.017; r(p)  = -0.206, P = 0.019, respectively). The number of acute respiratory tract infection (ARTI) episodes in the last 6 months was negatively correlated with serum TAC and hair Zn levels (r(p)  = -0.316, P < 0.001, and r(p)  = -0.196, P = 0.025, respectively). In this study, we found that TAC, hair Zn, and hair Se levels were lower in children with RW than HC and negatively correlated with wheezing episodes in the last 6 months. Also body Zn and Se levels can be reliably measured in hair samples.

Maternal fecundity and asthma among offspring-is the risk programmed preconceptionally? Retrospective observational study

OBJECTIVE

To evaluate the association between maternal fecundity factors and time to pregnancy and risk of asthma in offspring.

DESIGN

Retrospective observational hospital-based birth cohort study.

SETTING

A university-based obstetrics and gynecology department.

PATIENT(S)

A total of 40,914 women, who delivered between 1989 and 2007, were linked with the register for asthma reimbursement (n = 2,577) for their offspring. Fecundity factors were recorded during pregnancy. Logistic regression analyses were used.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Asthma among offspring.

RESULT(S)

The risk of asthma was significantly increased if the mother had any infertility problems (adjusted odds ratio [adjusted OR] 1.39, 95% confidence interval [CI] 1.19-1.63), medical infertility treatment (aOR 1.43, 95% CI 1.13-1.80), or any infertility treatment (aOR 1.50, 95% CI 1.26-1.79). The risk of asthma among offspring was also higher among mothers who had more than two miscarriages (aOR 1.25, 95% CI 1.04-1.51) and time to pregnancy over 3 months (aOR 1.25, 95% CI 1.07-1.45).

CONCLUSION(S)

These findings suggest that maternal subfertility exposes offspring to an increased risk of asthma.

CLINICAL TRIAL REGISTRATION NUMBER

The study is registered in Kuopio University Hospital register (TUTKI): ID 5302448.

EAACI: A European Declaration on Immunotherapy. Designing the future of allergen specific immunotherapy

Allergy today is a public health concern of pandemic proportions, affecting more than 150 million people in Europe alone. In view of epidemiological trends, the European Academy of Allergy and Clinical Immunology (EAACI) predicts that within the next few decades, more than half of the European population may at some point in their lives experience some type of allergy.

Not only do allergic patients suffer from a debilitating disease, with the potential for major impact on their quality of life, career progression, personal development and lifestyle choices, but they also constitute a significant burden on health economics and macroeconomics due to the days of lost productivity and underperformance. Given that allergy triggers, including urbanization, industrialization, pollution and climate change, are not expected to change in the foreseeable future, it is imperative that steps are taken to develop, strengthen and optimize preventive and treatment strategies.

Allergen specific immunotherapy is the only currently available medical intervention that has the potential to affect the natural course of the disease. Years of basic science research, clinical trials, and systematic reviews and meta-analyses have convincingly shown that allergen specific immunotherapy can achieve substantial results for patients, improving the allergic individuals’ quality of life, reducing the long-term costs and burden of allergies, and changing the course of the disease. Allergen specific immunotherapy not only effectively alleviates allergy symptoms, but it has a long-term effect after conclusion of the treatment and can prevent the progression of allergic diseases.

Unfortunately, allergen specific immunotherapy has not yet received adequate attention from European institutions, including research funding bodies, even though this could be a most rewarding field in terms of return on investments, translational value and European integration and, a field in which Europe is recognized as a worldwide leader. Evaluation and surveillance of the full cost of allergic diseases is still lacking and further progress is being stifled by the variety of health systems across Europe. This means that the general population remains unaware of the potential use of allergen specific immunotherapy and its potential benefits.

We call upon Europe’s policy-makers to coordinate actions and improve individual and public health in allergy by:

Promoting awareness of the effectiveness of allergen specific immunotherapy

Updating national healthcare policies to support allergen specific immunotherapy

Prioritising funding for allergen specific immunotherapy research

Monitoring the macroeconomic and health economic parameters of allergy

Reinforcing allergy teaching in medical disciplines and specialties

The effective implementation of the above policies has the potential for a major positive impact on European health and well-being in the next decade.

Associations and interactions of genetic polymorphisms in innate immunity genes with early viral infections and susceptibility to asthma and asthma-related phenotypes

BACKGROUND

The innate immune system is essential for host survival because of its ability to recognize invading pathogens and mount defensive responses.

OBJECTIVES

We sought to identify genetic associations of innate immunity genes with atopy and asthma and interactions with early viral infections (first 12 months of life) in a high-risk birth cohort.

METHODS

Three Canadian family-based studies and 1 Australian population-based case-control study (n = 5565) were used to investigate associations of 321 single nucleotide polymorphisms (SNPs) in 26 innate immunity genes with atopy, asthma, atopic asthma, and airway hyperresponsiveness. Interactions between innate immunity genes and early viral exposure to 3 common viruses (parainfluenza, respiratory syncytial virus, and picornavirus) were examined in the Canadian Asthma Primary Prevention Study by using both an affected-only family-based transmission disequilibrium test and case-control methods.

RESULTS

In a joint analysis of all 4 cohorts, IL-1 receptor 2 (IL1R2) and Toll-like receptor 1 (TLR1) SNPs were associated with atopy after correction for multiple comparisons. In addition, an NFKBIA SNP was associated with atopic asthma. Six SNPs (rs1519309 [TLR3], rs740044 [ILIR2], rs4543123 [TLR1], rs5741812 [LBP], rs917998 [IL18RAP], and rs3136641 [NFKBIB]) were significant (P < .05, confirmed with 30,000 permutations) in both the combined analysis of main genetic effects and SNP-virus interaction analyses in both case-control and family-based methods. The TLR1 variant (rs4543123) was associated with both multiple viruses (respiratory syncytial virus and parainfluenza virus) and multiple phenotypes.

CONCLUSION

We have identified novel susceptibility genes for asthma and related traits and interactions between these genes and early-life viral infections.