Changes in the prevalence of asthma, eczema and hay fever in pre-pubertal children: a 40-year perspective

Is asthma in children still increasing? 20-year prevalence trends in northern Sweden

BACKGROUND

In the present study, we describe prevalence trends of asthma and investigate the association with asthma symptoms, use of asthma medication, and asthma severity among 8-year-old children in Norrbotten, Sweden in 1996, 2006, and 2017.

METHODS

Within the Obstructive Lung Disease in Northern Sweden (OLIN) studies, three pediatric cohorts were recruited in 1996, 2006, and 2017 respectively. Identical methods were used; all children in first and second grade (median age 8 years) in three municipalities were invited to a parental questionnaire survey, completed by n = 3430 in 1996 (97% participation), n = 2585 in 2006 (96%), and n = 2785 in 2017 (91%). The questionnaire included questions about respiratory symptoms and diagnosis, treatment, and severity of asthma.

RESULTS

The prevalence of wheezing was stable during the study, 10.1% in 1996; 10.8% in 2006; and 10.3% in 2017, p = .621, while physician-diagnosed asthma increased: 5.7%, 7.4%, and 12.2%, p < .001. The use of asthma medication in the last 12 months increased: 7.1%, 8.7%, and 11.5%, p < .001. Among children diagnosed with asthma, the prevalence of asthma symptoms, the impact on daily life, and severe asthma decreased, while the use of inhaled corticosteroids increased from 1996 until 2017.

CONCLUSION

The prevalence of wheezing was stable among 8-year-old in this area from 1996 to 2017, while the prevalence of physician-diagnosed asthma doubled but without an increase in asthma morbidity. The increase of physician-diagnosed asthma without a coincident increase in asthma morbidity can partly be explained by more and earlier diagnosis among those with mild asthma.

Diverging trends of respiratory allergies and eczema in Greek schoolchildren: Six surveys during 1991-2018

Background: The prevalence of childhood asthma, rhinoconjunctivitis, and eczema in the city of Patras, Greece, has been followed in four consecutive surveys since 1991. After a continuous rise in the prevalence of all three of these disorders, a plateau was reached for asthma between 2003 and 2008, whereas the prevalence of rhinoconjunctivitis and eczema continued to increase. Objective: To investigate these trends in the same population into the following decade. Methods: We repeated two methodologically identical cross-sectional parental questionnaire surveys in 2013 and 2018 among 8-9-year-old schoolchildren (N = 2554 and N = 2648, respectively). In 2018, spirometry and fractional exhaled nitric oxide (FeNO) measurements were also performed. Results: Current asthma (i.e., wheeze/asthma in the past 2 years) decreased from 6.9% in 2008 to 5.2% in 2013 and 4.3% in 2018 (p for trend < 0.001). The prevalence of lifetime ("ever had") rhinoconjunctivitis also declined (5.1% in 2008, 4.4% in 2013, 3.0% in 2018; p for trend < 0.001), whereas that of lifetime eczema increased (10.8%, 13.6%, and 16.1%, respectively; p for trend < 0.001). The relative risk of current asthma in children with ever-had rhinoconjundtivitis was 7.73 in 2008, 6.00 in 2013, and 6.69 in 2018, whereas the relative risk in those with ever-had eczema was 5.15, 2.80, and 2.22, respectively. Among children with asthma, those with rhinoconjunctivitis had lower forced expiratory volume in the first second of expiration and higher FeNO values than those with eczema. Conclusion: The prevalence of asthma and rhinoconjunctivitis declined during the past decade in Greek schoolchildren, whereas the prevalence of eczema continued to rise. Nevertheless, the relationship between rhinoconjunctivitis and asthma remained strong, whereas the association between eczema and asthma appears to have weakened.

The evidence for interventions in early childhood allergy prevention - towards a living systematic review: protocol

Background: Research in early childhood allergy prevention (ECAP) is flourishing and new intervention strategies have proven to be promising. Due to the dynamic nature of ECAP, gaps between what is known and how guidelines inform practice are likely. A living systematic review (LSR) can narrow this gap by incorporating new evidence as it becomes available. No efficacy comparisons across various ECAP interventions for similar outcomes have been carried out. Networks of randomised clinical trials can be evaluated in the context of a network meta-analysis (NMA). We aim to establish a LSR on the efficacy and safety of any intervention investigated in randomised controlled trials (RCT) to prevent the occurrence of allergic sensitisation (AS), symptoms or diagnoses of allergic diseases in infancy and early childhood (0-3 years). Methods: A baseline SR will synthesise the evidence from existing SRs of RCTs as well as RCTs not yet considered in these. After completion of the baseline SR we propose to conduct a LSR. Using this methodology, we aim to undertake constant evidence surveillance, three-monthly search updates, and review updates every three months, should new evidence emerge. Conclusions: The ECAP evidence landscape has undergone dramatic transformations and this process is likely to continue. As a response to this, a LSR offers the potential to allow more timely synthesis of new evidence as it emerges. Long gaps between updates of SRs makes it harder for guidelines and recommendations to be up to date. Users of information, such as parents, may be confused if they encounter new evidence that is not part of a trusted guideline. A LSR approach allows us to continuously search the literature and update the evidence-base of existing ECAP interventions resulting in a decreased timespan from evidence accrual to informing clinical practice.

Pharmacoeconomics of allergy immunotherapy versus pharmacotherapy

Introduction: The purpose of this review is to evaluate the cost-effectiveness of allergy immunotherapy (AIT) in the treatment of allergic rhinitis, asthma, and other allergic conditions.Area covered: An extensive search of the PubMed and Medline database (January 1996 up to June of 2020) was conducted using the search terms allergy immunotherapy, pharmacoeconomics, cost-effectiveness, allergic rhinitis, and asthma. Studies were included if they included information on the economics of AIT in comparison to pharmacotherapy in the treatment of allergic rhinitis or asthma either as actual costs or based on theoretical models. Systematic reviews were included if they included information about the cost-effectiveness of AIT.Most clinical trials found significant cost-savings with AIT. The cost-effective time-point ranged from a few months to several years after treatment initiation.. Cost savings were demonstrated as early as 3 months after treatment initiation and were as great as 80% less than SDT in some studies.Expert opinion: There is strong evidence in the collective literature that AIT is cost-effective as compared to SDT alone. The magnitude of AIT's cost-effectiveness is likely underestimated because most of the studies considered during treatment costs and not AIT's long-term benefits or preventive/prophylactic effects or its impact on co-morbid conditions.

Dietary Habits in Children with Respiratory Allergies: A Single-Center Polish Pilot Study

BACKGROUND

The rising trend in allergic diseases has developed in parallel with the increasing prevalence of obesity, suggesting a possible association. The links between eating habits and allergies have not been sufficiently clarified.

AIM

To evaluate the nutritional status, eating habits, and risk factors of obesity and pulmonary function in children with allergic rhinitis.

MATERIALS AND METHODS

We evaluated 106 children with allergic rhinitis (mean age 12.1 ± 3.4 years; M/F 60/46) from the Department of Allergology. Clinical data were collected regarding allergies, physical activity, nutritional status (Bodystat), dietary habits (Food Frequency Questionnaire validated for the Polish population), skin prick test with aeroallergens (Allergopharma), and spirometry (Jaeger).

RESULTS

All children suffered from allergic rhinitis; among them, 43 (40.6%) presented symptoms of asthma. There were differences between children with only allergic rhinitis (AR group) and children with both rhinitis and asthma (AA group) in pulmonary function (forced expiratory volume in one second (FEV₁) 100 ± 11 vs. 92.1 ± 15.0; p < 0.05). A total of 84 children (79%) presented a normal body mass index (BMI) (10-97 percentile), 8 (7.5%) were underweight, and 14 (13.5%) were overweight or obese. There were no differences in body composition between the AR and AA groups. Incorrect eating habits were demonstrated by most of the children, e.g., consumption of three or fewer meals in a day (38%), sweets every day (44%), snacking between meals every day (80%), and eating meals less than 1 h before bedtime (47%). Compared to the AR group, the AA group was more likely to eat more meals a day (p = 0.04), snack more often (p = 0.04), and eat before sleeping (p = 0.005). Multiple regression analysis showed a significant association between high BMI and snacking between meals and low physical activity (adjusted R² = 0.97; p < 0.05).

CONCLUSIONS

The risk factors for obesity in children with allergies include snacking and low physical activity. Most children with respiratory allergies, especially those with asthma, reported incorrect eating habits such as snacking and eating before bedtime. A correlation between pulmonary function and body composition or dietary habits was not found.

Asthma: A Loss of Post-natal Homeostatic Control of Airways Smooth Muscle With Regression Toward a Pre-natal State

The defining feature of asthma is loss of normal post-natal homeostatic control of airways smooth muscle (ASM). This is the key feature that distinguishes asthma from all other forms of respiratory disease. Failure to focus on impaired ASM homeostasis largely explains our failure to find a cure and contributes to the widespread excessive morbidity associated with the condition despite the presence of effective therapies. The mechanisms responsible for destabilizing the normal tight control of ASM and hence airways caliber in post-natal life are unknown but it is clear that atopic inflammation is neither necessary nor sufficient. Loss of homeostasis results in excessive ASM contraction which, in those with poor control, is manifest by variations in airflow resistance over short periods of time. During viral exacerbations, the ability to respond to bronchodilators is partially or almost completely lost, resulting in ASM being "locked down" in a contracted state. Corticosteroids appear to restore normal or near normal homeostasis in those with poor control and restore bronchodilator responsiveness during exacerbations. The mechanism of action of corticosteroids is unknown and the assumption that their action is solely due to "anti-inflammatory" effects needs to be challenged. ASM, in evolutionary terms, dates to the earliest land dwelling creatures that required muscle to empty primitive lungs. ASM appears very early in embryonic development and active peristalsis is essential for the formation of the lungs. However, in post-natal life its only role appears to be to maintain airways in a configuration that minimizes resistance to airflow and dead space. In health, significant constriction is actively prevented, presumably through classic negative feedback loops. Disruption of this robust homeostatic control can develop at any age and results in asthma. In order to develop a cure, we need to move from our current focus on immunology and inflammatory pathways to work that will lead to an understanding of the mechanisms that contribute to ASM stability in health and how this is disrupted to cause asthma. This requires a radical change in the focus of most of "asthma research."

BSACI guideline for the diagnosis and management of allergic and non-allergic rhinitis (Revised Edition 2017; First edition 2007)

This is an updated guideline for the diagnosis and management of allergic and non-allergic rhinitis, first published in 2007. It was produced by the Standards of Care Committee of the British Society of Allergy and Clinical Immunology, using accredited methods. Allergic rhinitis is common and affects 10-15% of children and 26% of adults in the UK, it affects quality of life, school and work attendance, and is a risk factor for development of asthma. Allergic rhinitis is diagnosed by history and examination, supported by specific allergy tests. Topical nasal corticosteroids are the treatment of choice for moderate to severe disease. Combination therapy with intranasal corticosteroid plus intranasal antihistamine is more effective than either alone and provides second line treatment for those with rhinitis poorly controlled on monotherapy. Immunotherapy is highly effective when the specific allergen is the responsible driver for the symptoms. Treatment of rhinitis is associated with benefits for asthma. Non-allergic rhinitis also is a risk factor for the development of asthma and may be eosinophilic and steroid-responsive or neurogenic and non- inflammatory. Non-allergic rhinitis may be a presenting complaint for systemic disorders such as granulomatous or eosinophilic polyangiitis, and sarcoidoisis. Infective rhinitis can be caused by viruses, and less commonly by bacteria, fungi and protozoa.

Target-Recycling-Amplified Colorimetric Detection of Pollen Allergen Using Non-Cross-Linking Aggregation of DNA-Modified Gold Nanoparticles

Increasing prevalence of pollen allergies has raised concerns about human health. Development of a facile and precise method to detect pollen allergens would thus be of significance for environmental assessments and medical diagnoses. Here we report a sensitive colorimetric method to detect the Japanese cedar pollen allergen, Cry j 2. The method consists of two steps: a signal amplification based on the catalytic DNA hairpin self-assembly, followed by a signal transduction using the salt-induced non-cross-linking aggregation of gold nanoparticles densely modified with short DNA. The assay exhibits a detection limit of 0.2 ng/mL, which is 130-fold greater than that of the previously reported one. Moreover, the assay enables the detection of Cry j 2 spiked in soil solutions by avoiding any interference from the contaminants. The signal amplification system includes an anti-Cry j 2 DNA aptamer, which accounts for the absence of false responses to five nontarget allergen proteins. The present method could be of general applicability to various proteins by using appropriate aptamers.

Changes in the relationship between asthma and associated risk factors over fifty years

BACKGROUND

Childhood asthma is a common condition whose prevalence is changing. We hypothesized that the relationship between asthma and associated risk factors has changed over a 50-year period.

METHODS

An ecological study design was used. Children aged 8-13 attending schools in Aberdeen city were surveyed on seven occasions between 1964 and 2014. The following were determined: history of asthma, history of eczema, parental smoking, parental asthma, sex and socio-economic status. Analysis was by a structural change model with two knots. The outcome reported was the change in odds ratio between asthma and a given risk factor during a given period.

RESULTS

There were 23,241 questionnaires distributed and 17,439 returned (75%). The odds ratio (OR) for a child with asthma to have eczema increased between 1989 and 1999 by 1.031 [95% CI 1.028, 1.035] and by 1.042 between 2004 and 2014 [1.038, 1.047]. The OR for a child with asthma to have a parent who smoked rose by 1.032 [1.028, 1.036] between 1989 and 1999 and by 1.043 [1.038, 1.047] between 2004 and 2014), and to have a parent with asthma (1.027 [1.022, 1.031] for 1994-99 and 1.042 [1.037, 1.048] for 2004-2014). The OR for a child with asthma being male, but not and being from the most deprived communities, rose between 1989-1999 and 2004-2014.

CONCLUSIONS

The relationship between asthma prevalence and particular risk factors changed over the 50-year period of study, and this might reflect changes in children's environment and/or susceptibility.

A randomised placebo-controlled trial of oral and topical antibiotics for children with clinically infected eczema in the community: the ChildRen with Eczema, Antibiotic Management (CREAM) study

BACKGROUND

Secondary skin infection is common during eczema exacerbations and many children are treated with antibiotics when this is suspected, although there is little high-quality evidence to justify this practice.

OBJECTIVE

To determine the clinical effectiveness of oral and topical antibiotics, in addition to standard treatment with emollients and topical corticosteroids, in children with clinically infected eczema.

DESIGN

Multicentre randomised, double-blind, placebo-controlled trial.

SETTING

General practices and dermatology clinics in England, Wales and Scotland.

PARTICIPANTS

Children (aged 3 months to < 8 years) with a diagnosis of eczema (according to U.K. Working Party definition) and clinical suspicion of infection.

INTERVENTIONS

(1) Oral flucloxacillin and topical placebo; (2) topical fusidic acid (Fucidin(®), Leo Laboratories Limited) and oral placebo; and (3) oral and topical placebos, all for 1 week.

MAIN OUTCOME MEASURES

Patient-Orientated Eczema Measure (POEM) at 2 weeks (assessing subjective severity in the week following treatment).

RESULTS

We randomised 113 children (36 to oral antibiotic, 37 to topical antibiotic and 40 to placebo), which was fewer than our revised target sample size of 282. A total of 103 (92.0%) children had one or more clinical features suggestive of infection and 78 (69.6%) children had Staphylococcus aureus cultured from a skin swab. Oral and topical antibiotics resulted in a 1.52 [95% confidence interval (CI) -1.35 to 4.40] and 1.49 (95% CI -1.55 to 4.53) increase (worse subjective severity) in POEM score at 2 weeks, relative to placebo and controlling for baseline POEM score. Eczema Area and Severity Index (objective severity) scores were also higher (worse) in the intervention groups, at 0.20 (95% CI -0.12 to 0.52) and 0.42 (95% CI 0.09 to 0.75) for oral and topical antibiotics, respectively, at 2 weeks. Analyses of impact on the family, quality of life, daily symptom scores, and longer-term outcomes were all consistent with the finding of no or limited difference and a trend towards worse outcomes in the intervention groups. Sensitivity analyses, including adjusting for compliance and imputation for missing data, were consistent with the main findings.

CONCLUSIONS

Our data suggest that oral and topical antibiotics have no effect, or a harmful effect, on subjective eczema severity in children with clinically infected eczema in the community. The CIs around our estimates exclude a meaningful beneficial effect (published minimal clinically important difference for POEM is 3.4). Although most patients in this trial had features suggestive of infection and S. aureus on their skin, participants primarily had mild-moderate eczema and those with signs of more severe infection were often excluded. Clinicians should consider avoiding oral and topical antibiotic use in children with suspected infected eczema in the community who do not have signs of 'severe infection'. Further research should seek to understand how best to encourage the use of topical steroids and limit use of antibiotics in those with eczema flares without signs of severe infection, as well as developing tools to better phenotype eczema flares, in order to better define a population that may benefit from antibiotic treatment.

TRIAL REGISTRATION

European Union Drug Regulating Authorities Clinical Trials (EudraCT) number 2011-003591-37 and Current Controlled Trials ISRCTN96705420.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

No further increase in the parent reported prevalence of allergies in Bavarian preschool children: Results from three cross-sectional studies

BACKGROUND

After three decades of an increase in the prevalence of asthma and allergies, new findings show a plateau in the prevalence of industrialized nations. The objective of this study was to determine whether there was a change in the parent reported prevalence of asthma and allergies among Bavarian preschool children since 2004.

METHODS

A parent questionnaire was administered as part of the Bavarian school entrance examination in three cross-sectional studies from 2004/2005, 2006/2007 and 2012/2013. The questionnaire included items on allergy testing history, identified allergens, symptoms (e.g. wheezing, itchy eyes, rash), medically diagnosed asthma, hay fever and atopic dermatitis. Logistic regression was performed to observe time patterns and adjust for risk factors.

RESULTS

Data were available for 6350 (2004/2005), 6483 (2006/2007) and 5052 (2012/2013) individuals. Symptoms and diseases were more frequent in boys, except for allergies which affect the skin. From 2004 to 2012 the parent reported prevalence of asthma (2.6% to 2.8%), hay fever (4.7% to 4.0%) and atopic dermatitis (12.4% to 11.1%) either remained quite stable or decreased not significantly.

CONCLUSIONS

Results from these three cross-sectional surveys of parent reports suggest that the parent reported prevalences of asthma and allergies are quite stable with small fluctuations since 2004 for Bavarian preschool children. Future research is needed to determine if this trend will continue.

Trends and socioeconomic disparities in preadolescent's health in the UK: evidence from two birth cohorts 32 years apart

BACKGROUND

Compared to children and adults, little is known about changes in adolescent health over time. This study profiles the health of preadolescents in two distinct time periods, 1980 and 2012.

METHODS

Secondary analysis of the British Cohort Study and the Millennium Cohort Study for preadolescents mostly aged between 10 and 11.5 years (range 9.75-13 years). The prevalence/average of, and socioeconomic gradients in, the following were compared between 1980 and 2012; general health problems, anthropometrics, allergic conditions, infectious diseases, health service use, smoking and parental smoking behaviour and maternal adiposity. Socioeconomic status was measured by familial income (3 groups).

RESULTS

There were decreases in the proportion of hospital admissions (Δ=-0.10(-0.09:-0.11)) smoking (Δ=-0.12(-0.11:-0.13)), parental smoking (mother: (Δ=-0.19(-0.18:-0.21)) father: (Δ=-0.35(-0.34:-0.37), infectious diseases (measles: (Δ=-0.46(-0.45:-0.47)) whooping cough: (Δ=-0.07(-0.06:-0.07)) and hearing problems (Δ=-0.04(-0.03:-0.05)). There were no changes in limiting long-standing illness (Δ=0.00 (-0.00:0.00)), or the proportion of children having two or more accidents requiring medical attention (Δ=-0.02(-0.00:-0.02)). There were increases in the proportion overweight (Δ=0.18(0.17:0.19)), maternal overweight(Δ=0.22(0.21:0.23)) and obesity(Δ=0.12(0.11:0.13)), height for age(Δ=0.47(0.44:0.49)), weight for age (Δ=0.68(0.65:0.71)), proportion reporting chicken pox (Δ=0.28(0.27:0.29)), allergic conditions (eczema Δ=0.19(0.18:0.20)), asthma Δ=0.12(0.11:0.13), hay fever Δ=0.15(0.14:0.16)) and wearing glasses (Δ=0.08(0.07:0.09)). There were increases in socioeconomic gradients for limiting long-standing illness, smoking, overweight, weight for age, height for age, wearing glasses, asthma and the onset of puberty.

CONCLUSIONS

There have been reductions in infectious diseases and tobacco exposure among British preadolescents, but overweight and allergic conditions have risen dramatically. Children from deprived families have benefitted least from improvements in health status, and have experienced the largest increases in health risks.

Diverging prevalences and different risk factors for childhood asthma and eczema: a cross-sectional study

OBJECTIVE

To compare the prevalences of and risk factors for asthma, wheeze, hay fever and eczema in primary schoolchildren in Aberdeen in 2014.

DESIGN

Cross-sectional survey.

SETTING

Primary schools in Aberdeen, North-East Scotland.

PARTICIPANTS

Children in Scottish school years primary 1-7 were handed a questionnaire by their class teacher to be completed by their parents and returned to the researchers by post or online.

MAIN OUTCOME MEASURES

Lifetime history of asthma, eczema and hay fever, and recent history of wheeze.

RESULTS

41 schools agreed to participate (87%). 11,249 questionnaires were distributed and 3935 returned (35%). A parent-reported lifetime history of asthma, eczema and hay fever was present in 14%, 30% and 24% of children, respectively. The odds of lifetime asthma increased with age (OR 1.1 per year, 95% CI 1.1 to 1.2), male sex (OR 1.89, 95% CI 1.4 to 2.3), parental smoking (OR 1.7, 95% CI 1.2 to 2.3) and eczema (OR 6.6, 95% CI 5.2 to 8.4). Prevalence of recent wheeze was also reported to be 14% and was positively associated with male sex, parental smoking and eczema. In contrast, parental eczema was the only identified predictor of childhood eczema risk.

CONCLUSIONS

The lifetime prevalence of asthma in primary schoolchildren was 14% in this survey, approximately half the prevalence of eczema. We report diverging prevalences in relation to previous studies in our locality, and different risk factors for asthma and eczema. These findings suggest that asthma and eczema are unlikely to have a common origin.

Incidence rates of atopic dermatitis, asthma, and allergic rhinoconjunctivitis in Danish and Swedish children

BACKGROUND

Several studies have shown that the prevalence of the frequent chronic conditions of atopic dermatitis, asthma, and allergy has increased substantially for reasons not fully understood. Atopic diseases affect quality of life in both children and their family members.

OBJECTIVE

Using national registers, we sought to establish up-to-date incidence rates of atopic dermatitis, asthma, and allergic rhinoconjunctivitis in the Danish and Swedish child populations.

METHODS

Children born in Denmark from 1997 to 2011 or born in Sweden from 2006 to 2010 participated in this cross-national, population-based cohort study. Incidence rates of atopic dermatitis, asthma, and allergic rhinoconjunctivitis in the Danish and Swedish child cohorts were ascertained through disease-specific dispensed prescribed medication, specific hospital contacts, or both.

RESULTS

In both countries the incidence rate of atopic dermatitis was stable during the study periods. The incidence rate of asthma increased until 2006 and stabilized for the rest of the study period in Denmark and increased in Sweden. The incidence rate of allergic rhinoconjunctivitis decreased in both countries.

CONCLUSION

The study revealed similar trends, with stable incidence rates of atopic dermatitis in both Danish and Swedish children, an increase and then stabilization in asthma incidence rates in Denmark and an increase in Sweden, and a decrease in allergic rhinoconjunctivitis incidence rates. At age 5 years, one third of all children were affected with at least one of the conditions of atopic dermatitis, asthma, or allergic rhinoconjunctivitis.

From the outside-in: Epidermal targeting as a paradigm for atopic disease therapy

Atopic dermatitis (AD) is a chronic inflammatory skin disorder which can precede asthma and allergic rhinitis in a disease trajectory known as the atopic march. The pathophysiology of AD includes cutaneous inflammation, disrupted epidermal barrier function, xerosis and propensity to secondary infections. AD had previously been thought to arise from the systemic atopic immune response and therapies are therefore directed towards ameliorating Th2-mediated inflammation. However in recent years the focus has shifted towards primary defects in the skin barrier as an initiating event in AD. Links between loss-of-function variants in the gene encoding filaggrin and disrupted activity of epidermal serine proteases and AD have been reported. Based on these observations, a mechanism has been described by which epidermal barrier dysfunction may lead to inflammation and allergic sensitization. Exogenous and endogenous stressors can further exacerbate inherited barrier abnormalities to promote disease activity. Pathways underlying progression of the atopic march remain unclear, but recent findings implicate thymic stromal lymphopoietin as a factor linking AD to subsequent airway inflammation in asthma. This new appreciation of the epidermis in the development of AD should lead to deployment of more specific strategies to restore barrier function in atopic patients and potentially halt the atopic march.

Prevalence of asthma and allergic diseases in adolescents: nine-year follow-up study (2003-2012)

OBJECTIVE

To determine the prevalence of symptoms of asthma, rhinitis, and atopic eczema in adolescents (AD; 13-14 years) living in seven Brazilian cities, by applying the standardized written questionnaire (WQ) of the International Study of Asthma and Allergies in Childhood (ISAAC), and to evaluate the time trend nine years after the last assessment of ISAAC phase 3 (ISP3).

METHODS

The ISAAC-WQ was answered by 20,099 AD from the Northern, Northeastern, Southeastern, and Southern Brazilian regions. Values obtained were compared to those observed in ISP3 using nonparametric (chi-squared or Fisher) tests, and the ratio of annual increment/decrement was established for each of the centers, according to the symptom assessed.

RESULTS

Considering the national data and comparing to values of ISP3, there was a decrease in the mean prevalence of active asthma (18.5% vs. 17.5%) and an increase in the frequency of severe asthma (4.5% vs. 4.7%) and physician-diagnosed asthma (14.3% vs. 17.6%). An increase in prevalence of rhinitis, rhinoconjunctivitis, and atopic eczema was also observed.

CONCLUSIONS

The prevalence of asthma, rhinitis, and atopic eczema in Brazil was variable; higher prevalence values, especially of asthma and eczema, were observed in regions located closer to the Equator.

Is the impact of atopic disease on children and adolescents' health related quality of life modified by mental health? Results from a population-based cross-sectional study

Background

Eczema, asthma and hay fever are global health problems and their prevalence has increased considerably over the last decades. All appear to share an underlying atopic diathesis but their aetiology is considered to be multifactorial. They have been linked to decreases in health related quality of life (HRQoL) in adults, children/adolescents and/or parents of children. Research also suggests an association of the three conditions with mental health, which in turn is related to HRQoL decreases. We aimed to assess whether the impact of any of the three conditions on HRQoL is modified by presence of mental health problems.

Methods

The impact of occurrence of the three conditions within the past four weeks and 12 months on HRQoL, as measured by the ‘Quality of Life in Children – Revised’ (KINDL-R) questionnaire was analysed by use of the complex sample general linear model in a population-based sample (N = 6518) of children and adolescents aged 11 – 17. Analyses were adjusted for the other atopic conditions, sociodemographic and clinical variables and stratified for mental health as measured by the Strengths and Difficulties Questionnaire (SDQ) (normal n = 5697, borderline n = 609, abnormal n = 193).

Results

Eczema and hay fever within the past four weeks were significantly associated with decreased total or certain subscales of KINDL-R after adjusting for all other variables when no mental health abnormalities were present while asthma was associated with better HRQoL in these individuals. However, when mental health problems were present, eczema was positively associated with several subscales and the positive impact of asthma was stronger. The presence of mental health problems accentuated the negative relationship between hay fever and HRQoL (stronger negative impact). However, due to decreasing numbers in the group with mental health problems only few associations reached statistical significance.

Conclusions

While the results suggest mental health to have a modifying effect on the relationship between some atopic conditions and HRQoL caution needs to be exercised in interpreting the results: First, the groups with borderline or abnormal mental health were comparably smaller than the group with normal mental health. In the group with normal mental health small effects were more likely to become significant than in the other two groups. Secondly some problems regarding the validity of the self-report SDQ still remain.

Prevalence and risk factors of atopic diseases in German children and adolescents

BACKGROUND

Atopic diseases became an important health problem in affluent Western societies.

METHODS

To study the prevalence and factors associated with the risk of atopic diseases in Germany, data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) were analysed (n = 17,450). Standardized, computer-assisted personal interviews with parents and parent-administered questionnaires provided physician diagnoses of allergic rhinoconjunctivitis, atopic dermatitis and asthma as well as data on demographic characteristics, migration background, birth order, age at the beginning of nursery, atopic diseases of parents, parents' smoking status, parents' occupation, breastfeeding and living environment.

RESULTS

The life-time prevalence of atopic dermatitis was 13.2% (95% confidence limit: 12.5-13.9%), 10.7% (10.1-11.3%) for allergic rhinoconjunctivitis and 4.7% (4.3-5.1%) for asthma. At least one atopic disease in parents was the strongest factor associated with atopic diseases in the offspring, with a prevalence ratio of up to 2.6. High and middle socio-economic status (prevalence ratio, 95% confidence limit: 1.28, 1.12-1.46; 1.15, 1.01-1.32) were associated with the risk of atopic dermatitis, whereas a two-sided background of migration reduced the risk (0.76, 0.65-0.88). Factors that reduced the risk of allergic rhinoconjunctivitis were parents working as self-employed farmers (0.48, 0.30-0.76) and older siblings (0.80, 0.71-0.89), whereas the beginning of nursery school at older age was associated with an increased risk in children who were cared for outside the family before school age (1.05, 1.00-1.10). Living in mould-infested rooms (1.64, 1.23-2.19), an urban living environment (1.20, 1.02-1.42) and a smoking mother and/or father (1.20, 1.02-1.40) were associated with the risk of asthma.

CONCLUSIONS

Our results are in line with the so-called 'hygiene hypothesis', which emphasizes the role of environmental factors in addition to a genetic predisposition in the development of atopic diseases. Research on factors associated with atopic diseases can facilitate decisions on preventive strategies. Further studies are needed to explore trends in prevalence and risk factors for atopic diseases.

A novel dietary intervention to optimize vitamin E intake of pregnant women to 15 mg/day

Associations have been reported between suboptimal maternal vitamin E intake during pregnancy and childhood asthma. This pilot study conducted in 2008/2009 investigated the feasibility and acceptability of a food-based randomized controlled trial in pregnant women to optimize dietary vitamin E intake to 15 mg/day. A food-based intervention using "food exchanges" to individually optimize dietary vitamin E intake to 15 mg/day was developed and included in an advice booklet. Forty-three pregnant women with a personal/partner history of asthma were recruited at 12 weeks gestation and randomized to food-based intervention or a control group until 20 weeks gestation. A registered dietitian assessed the vitamin E intake of 22 women and provided tailored advice on food-based exchanges to optimize their intake to 15 mg/day. The 21 control women were not given dietary advice. The food-based intervention was completed by 19 women and increased mean vitamin E intake: food diary data, 7.13 mg/day (95% confidence interval: 5.63 to 18.6) to 17.4 mg/day (95% confidence interval: 14.4 to 20.5) (P<0.001). This pilot study demonstrates the feasibility and acceptability of a food-exchange-based intervention to optimize dietary vitamin E intake during pregnancy. Additional work is required to determine whether this intervention, if sustained for the rest of pregnancy, reduces the likelihood of childhood asthma. The methodology used in the design of this novel food-based intervention could be transferred to other nutrients.

Investigating international time trends in the incidence and prevalence of atopic eczema 1990-2010: a systematic review of epidemiological studies

The prevalence of atopic eczema has been found to have increased greatly in some parts of the world. Building on a systematic review of global disease trends in asthma, our objective was to study trends in incidence and prevalence of atopic eczema. Disease trends are important for health service planning and for generating hypotheses regarding the aetiology of chronic disorders. We conducted a systematic search for high quality reports of cohort, repeated cross-sectional and routine healthcare database-based studies in seven electronic databases. Studies were required to report on at least two measures of the incidence and/or prevalence of atopic eczema between 1990 and 2010 and needed to use comparable methods at all assessment points. We retrieved 2,464 citations, from which we included 69 reports. Assessing global trends was complicated by the use of a range of outcome measures across studies and possible changes in diagnostic criteria over time. Notwithstanding these difficulties, there was evidence suggesting that the prevalence of atopic eczema was increasing in Africa, eastern Asia, western Europe and parts of northern Europe (i.e. the UK). No clear trends were identified in other regions. There was inadequate study coverage worldwide, particularly for repeated measures of atopic eczema incidence. Further epidemiological work is needed to investigate trends in what is now one of the most common long-term disorders globally. A range of relevant measures of incidence and prevalence, careful use of definitions and description of diagnostic criteria, improved study design, more comprehensive reporting and appropriate interpretation of these data are all essential to ensure that this important field of epidemiological enquiry progresses in a scientifically robust manner.

Development and comorbidity of eczema, asthma and rhinitis to age 12: data from the BAMSE birth cohort

BACKGROUND

Allergy-related diseases are a public health issue, but knowledge on development and comorbidity among children is scarce. The aim was to study the development of eczema, asthma and rhinitis in relation to sex and parental allergy, in a population-based cohort, during childhood.

METHODS

At 1, 2, 4, 8 and 12 years, parental questionnaires were used to obtain data on allergy-related diseases. Complete data for all five follow-up occasions were available from 2916 children. Odds ratios for the risk of any allergy-related disease in relation to heredity and sex were calculated using generalized estimating equations.

RESULTS

At 12 years, 58% of the children had had eczema, asthma and/or rhinitis at some time. Disease turnover was high for all three diseases throughout the study. Comorbidity increased with age, and at 12 years, 7.5% of all the children were affected by at least two allergy-related diseases. Parental allergy was associated with increased comorbidity and more persistent disease and increased the risk of having any allergy-related disease (adjusted OR 1.76; 95% CI 1.57-1.97) up to 12 years. Male sex was associated with an increased risk throughout childhood. Boys and girls did not differ in disease persistence, and for comorbidity, the differences were minor.

CONCLUSIONS

Allergy-related diseases may affect a majority of children. Eczema, asthma and rhinitis develop dynamically throughout childhood, and allergic comorbidity is common. These findings indicate that allergy-related diseases should be neither seen nor studied as isolated entities.

Allergy-associated symptoms in relation to childhood non-Hodgkin's as contrasted to Hodgkin's lymphomas: a case-control study in Greece and meta-analysis

An increase of the prevalence of childhood allergic diseases and the incidence of childhood Hodgkin's (HL) and non-Hodgkin's lymphoma (NHL) were reported in the late 20th century. Among adults, several studies point to an inverse association with lymphoma; it remains to be confirmed whether allergy is also related to childhood lymphomas and whether the association, if any, is of an aetiologic nature. Between 1996 and 2008, 277 children (aged 0-14 years) with HL (N = 111) or NHL (N = 166) were enrolled in Nationwide Registry for Childhood Hematological Malignancies (NARECHEM), a Greek hospital-based-registry of childhood hematological malignancies. Hospital controls were individually matched to cases on age and sex. Multivariate conditional logistic regression was used to estimate odds ratios (ORs) with 95%confidence intervals (CIs) for associations of allergic diseases and other covariates with childhood HL or NHL risk. Subsequently, we combined our results with those of a French case-control study in a meta-analysis amounting to a total of 330 NHL cases/1478 controls and 239 HL cases/959 controls. After controlling for sociodemographic, perinatal and environmental factors, childhood NHL was less prevalent among children with allergy-associated symptoms overall (OR:0.50, 95%CI:0.27-0.92) or a history of asthma (OR:0.43, 95%CI:0.21-0.88). By contrast, allergy did not seem to be associated with childhood HL risk, although statistical power was limited. Fewer seaside holidays and higher birth weight were also associated with increased childhood NHL risk. The combined OR of the two studies for the association of asthma with NHL risk was: 0.52, 95%CI:0.32-0.84, whereas for HL: 0.86, 95%CI:0.51-1.45. Allergy seems to be strongly and inversely associated with childhood NHL. It remains to be elucidated in future investigations comprising larger populations, focusing on specific disease subtypes and employing more pertinent study-designs, whether this association is genuinely protective.

Prevalence of respiratory symptoms at two time points in a population of children in Manchester--a cohort study

OBJECTIVE

Although the prevalence of asthma and atopy has been noted to have increased in recent decades, patterns of asthma prevalence have, traditionally, been difficult to track. Most reports on trends in childhood asthma have been cross-sectional measuring the prevalence in cohorts of similar aged children at different time points. The aim of this paper is to report on the prevalence of symptoms in the same cohort at two separate time points.

DESIGN

Retrospective cohort study.

SETTING

Community-based study, Central Manchester.

PARTICIPANTS

MANCAS1, study n=5086, participation n=2414. MANCAS2, study n=6338, participation n=1608. Children born in a hospital in Manchester within specified dates and still living or attending a school in Central Manchester were eligible for inclusion. Children on an 'at-risk' register or living with short-term carers were excluded.

OUTCOME MEASURES

Data on respiratory symptoms were collected at two separate time points using parent completed questionnaires.

RESULTS

Response rate for MANCAS1 was 47.5% and 25.4% for MANCAS2. There were 801 individuals for whom a response to both studies was received. There was a significant reduction in the prevalence of night cough (29.5% vs 18.3%, McNemar <0.01) and antibiotic use for respiratory infections (9.1% vs 4.3%, McNemar <0.01) between the two study time points. The prevalence of hay fever/eczema increased (41.6% vs 46.9%, McNemar <0.01) between the two studies. There was no significant difference in the prevalence of wheeze, exercise-induced wheeze or asthma medication.

CONCLUSIONS

Although this report of respiratory symptom prevalence in the same population at two time points over a 7-year period shows a constant burden of asthma symptoms, there is some suggestion of variability in asthma symptom prevalence within the cohort as the children matured while the burden of allergy symptoms increased.

Assessment of a computerised decision support system for allergic rhino-conjunctivitis counselling in German pharmacy

OBJECTIVE

In a prospective two-phase intervention study we evaluated a newly developed computerised pharmacy decision support system (PDSS) for the counselling of patients with allergic rhinitis and conjunctivitis.

METHOD

Community pharmacists were invited to counsel a virtual patient in a first interview. Immediately thereafter, we trained pharmacists to operate the PDSS, which they applied in a second patient interview immediately following the training. We assessed the completeness of mandatory questions asked as defined by national guidelines.

RESULTS

Participating pharmacists (n = 50, 78% female, mean age 34 [IQR: 27-40] years, 8 [2-14.5] years of practical experience, 32% specialised in community pharmacy) asked considerably more mandatory questions to confirm appropriateness of self-medication with 7 (5.25-9; 78%) from 9 questions compared to 2 (1-3; 22%) without PDSS (median; P < 0.001). In particular, using the PDSS more than doubled mandatory questions (9/12, 6.25-10; 75% vs. 4/12, 3-5; 33%; P < 0.001) relevant for appropriate drug selection.

CONCLUSION

Pharmacists omitted many questions mandatory to assess whether self-medication is appropriate. Using the newly developed PDSS more than doubled the number of mandatory questions asked. The results suggest that the PDSS is ready for evaluation of its impact in real patients.

Effect of prenatal indoor pet exposure on the trajectory of total IgE levels in early childhood

BACKGROUND

The presence of pets in a home during the prenatal period and during early infancy has been associated with a lower prevalence of allergic sensitization and total IgE levels in middle childhood. No studies have examined the effect of pet exposure in a population-based cohort by using multiple early-life measures of serum total IgE.

OBJECTIVE

We sought to examine within-individual longitudinal trends in total IgE levels during early childhood and assess the effect of indoor prenatal pet exposure on those trends. Also, we sought to use a statistical method that was flexible enough to allow and account for unequally spaced study contacts and missing data.

METHODS

Using the population-based Wayne County Health, Environment, Allergy and Asthma Longitudinal Study birth cohort (62% African American), we analyzed 1187 infants with 1 to 4 measurements of total IgE collected from birth to 2 years of age. Effects of pet exposure on the shape and trajectory of IgE levels were assessed by using a multilevel longitudinal model, accommodating repeated measures, missing data, and the precise time points of data collection.

RESULTS

The best-fit shape to the trajectory of IgE levels was nonlinear, with an accelerated increase before 6 months. Total IgE levels were lower across the entire early-life period when there was prenatal indoor pet exposure (P < .001). This effect was statistically significantly stronger in children delivered by means of cesarean section versus those delivered vaginally (P < .001 and P < .06, respectively) and in those born to non-African American (P < .001) versus African American (P < .3) mothers.

CONCLUSION

Pet exposure and delivery mode might be markers of infant exposure to distinct microbiomes. The effect of exposures might vary by race, suggesting a differential effect by ancestry.

Diet and asthma: nutrition implications from prevention to treatment

Asthma is characterized by lung airway inflammation initiated and perpetuated by an inappropriate immune response, increased airway responsiveness, and variable airflow obstruction. In Western countries there has been a marked increase in asthma prevalence such that it has become a public health concern. It has been hypothesized that the increase may be due to changing antioxidant intake, increasing dietary ratio of n-6:n-3 polyunsaturated fatty acids (PUFA), and vitamin D deficiency (and supplementation). Observational studies have reported associations between asthma and dietary antioxidants (vitamin E, vitamin C, carotenoids, selenium, polyphenols, and fruit), PUFA, and vitamin D. However, supplementing the diets of adults with asthma with antioxidants and n-3 PUFA has minimal, if any, clinical benefit. Currently there is insufficient evidence to support the use of nutrient supplements to complement conventional treatment; however, results of ongoing studies are awaited, and additional research is required, particularly in children. Interest in the potential of dietary intervention during pregnancy to reduce the likelihood of childhood asthma has increased. A small number of cohort studies have highlighted associations between childhood asthma and reduced maternal intake of some nutrients (vitamin E, vitamin D, selenium, zinc, and PUFA) during pregnancy. Although vitamin D intervention studies during pregnancy are ongoing and two intervention studies suggest that dietary PUFA manipulation during pregnancy may be advantageous, further trials are needed to establish if modification of maternal nutrient intake during pregnancy can be used as a healthy, low cost, public health measure to reduce the prevalence of childhood asthma.

Children and adolescents' health-related quality of life in relation to eczema, asthma and hay fever: results from a population-based cross-sectional study

PURPOSE

Several studies have looked at the relationship between childhood atopic disease and health-related quality of life (HRQoL), but existing research is limited by selected populations, small samples or lack to consider each of the three atopic conditions simultaneously.

METHODS

Impact of 4-week and 12-month occurrences of the three conditions on HRQoL were analysed by the use of complex sample general linear models alone and adjusted for the other atopic conditions, sociodemographics and mental health in a population-based sample (n = 6,518) of children and adolescents aged 11-17.

RESULTS

In univariate analyses, total HRQoL was significantly impacted by eczema and hay fever but not asthma with stronger effects for 4-week occurrence. In multivariate analyses, 12-month occurrence of hay fever and 4-week occurrence of eczema and hay fever significantly impacted on total HRQoL. Although most of the variance in HRQoL was explained by mental health, independent effects of the atopic conditions remained.

CONCLUSION

Atopic conditions impact HRQoL over and above mental health. When analysing the relationship between atopic conditions and HRQoL, it is important to consider more immediate versus less immediate effects of the conditions. Extent of impairment and the domains affected appear to vary when different time intervals are used.

Session 1: Allergic disease: Nutrition as a potential determinant of asthma

Asthma is characterised by chronic lung airway inflammation, increased airway responsiveness and variable airflow obstruction. In Westernised countries asthma is a public health concern because of its prevalence, associated ill health and high societal and healthcare costs. In recent decades there has been a marked increase in asthma prevalence, particularly in Westernised countries. It has been proposed that changing diet has contributed to the increase in asthma. Several dietary hypotheses exist; the first relates the increase in asthma to declining dietary antioxidant intake, the second to decreased intake of long-chain n-3 PUFA and increasing intake of n-6 PUFA. Vitamin D supplementation and deficiency have also been hypothesised to have contributed to the increase in asthma. Observational studies have reported associations between asthma and dietary antioxidants (vitamin E, vitamin C, carotenoids, Se, flavonoids, fruit), lipids (PUFA, butter, margarine, fish) and vitamin D. However, supplementing the diets of adults with asthma with antioxidants and lipids has minimal, if any, clinical benefit. There is growing interest in the possibility that childhood asthma is influenced by maternal diet during pregnancy, with studies highlighting associations between childhood asthma and maternal intake of some nutrients (vitamin E, vitamin D, Se, PUFA) during pregnancy. It has been suggested that maternal diet during pregnancy influences fetal airway and/or immune development. Further intervention studies are needed to establish whether modification of maternal nutrient intake during pregnancy can be used as a healthy low-cost public health measure to reduce the prevalence of childhood asthma.