Development of allergies and asthma in infants and young children with atopic dermatitis--a prospective follow-up to 7 years of age

Food allergy and the development of asthma symptoms

Allergies are multifactorial diseases the onset of which depends also on genetic and environmental factors in early life. Thus, environmental factors can affect the immune response and modify lung development, thereby leading to asthma. The role of the factors used to date to predict asthma development is modest, and clinical criteria should always be considered in association with familiarity for atopy. The aim of this study is to evaluate the risk of asthma in a population with positive skin prick test (SPT) (which is a reliable marker of atopy) to food allergens, regardless of clinical manifestations in the early years of life. The cohort of children enrolled in our study who had a positive SPT to food in the first three years of life had a prevalence of asthma after 7-14 years, double that of the general pediatric population. This prevalence increased significantly in patients with SPT positivity for food and inhalant allergens. We identified a correlation between the sensitization profile in children under the age of 36 months and the development of asthma during a period of 7-14 years. This study confirms that early sensitization is an important risk factor for the development of asthma, particularly in association with sensitization to inhalants, and that the persistence of food sensitization in school-age children and adolescents is associated to more severe asthma.

Atopic dermatitis in a high-risk cohort: natural history, associated allergic outcomes, and risk factors

BACKGROUND

Atopic dermatitis (AD) is commonly associated with asthma and other atopic disorders in childhood.

OBJECTIVE

To evaluate the natural history of AD and its association with other allergic outcomes in a high-risk cohort through the age of 7 years.

METHODS

A total of 373 high-risk infants, who had undergone a randomized controlled trial with intervention measures for primary prevention of asthma applied during the first year of life, were assessed for asthma, AD, and allergic sensitization at 1, 2, and 7 years.

RESULTS

The multifaceted intervention program did not reduce AD despite reducing the prevalence of asthma significantly. Sixty-two children (16.6%) had AD during the first 2 years (early-onset AD); of these, 26 continue to have AD at the age of 7 years (persistent), whereas 36 no longer had the disease (nonpersistent) at the age of 7 years. Twenty-three children (6.2%) developed AD only after the age of 2 years (late-onset AD). Early-onset AD, persistent or nonpersistent, was associated with increased risk of allergic sensitization to food allergens within the first 2 years of life and asthma diagnosis at year 7. However, only persistent AD was associated with an increased risk of other atopic diseases and allergic sensitization to food and aeroallergens at year 7. Late-onset AD was not associated with atopic diseases or allergic sensitization at year 7 with the exception of Alternaria alternans.

CONCLUSION

In this cohort of infants at high risk of asthma, early-onset persistent AD, which was highly associated with atopic sensitization, increased the risk of atopic diseases in later childhood and thus appears to be part of the atopic march.

Clinico-etiological study with response to specific treatment in childhood urticaria

Background:

Urticaria is a common dermatological manifestation in adults with relatively infrequent occurrence of chronic urticaria (CU) in childhood. The etiology of urticaria in childhood remains incompletely understood because of limited data on children.

Objective:

We carried out this retrospective data-based study to determine different etiological factors and response to treatment in pediatric patients presenting with urticaria.

Materials and Methods:

Eighty children (M : F 49 : 31) between the ages of 1 and 14 years, who presented with urticaria excluding patients of physical urticaria attending the Outpatient Department of Pediatrics and Dermatology were included in the study. Patients were evaluated after taking a detailed history, doing a thorough physical examination, and basic laboratory investigations. Specific in vivo and in vitro tests were performed after the initial evaluation and consent of patients.

Results:

Out of eighty patients, 35 (43.75%) presented with acute urticaria and 45 (56.25%) gave a history of chronic urticaria.CU. An underlying cause was suspected in 53 cases (66.25%), although a definite association with response to a specific treatment was correlated in 30 (37.5%). Infection was the most common underlying causative factor. Underlying thyroid dysfunction was observed in 12 patients, of whom two had thyroid anti peroxidase antibodies. Autologous serum skin test was positive in 17 patients.

Conclusions:

In the present study infections were the most common etiological factor for urticaria in children.

Early eczema and the risk of childhood asthma: a prospective, population-based study

Background

Severe eczema in young children is associated with an increased risk of developing asthma and rhino-conjunctivitis. In the general population, however, most cases of eczema are mild to moderate. In an unselected cohort, we studied the risk of current asthma and the co-existence of allergy-related diseases at 6 years of age among children with and without eczema at 2 years of age.

Methods

Questionnaires assessing various environmental exposures and health variables were administered at 2 years of age. An identical health questionnaire was completed at 6 years of age. The clinical investigation of a random subsample ascertained eczema diagnoses, and missing data were handled by multiple imputation analyses.

Results

The estimate for the association between eczema at 2 years and current asthma at 6 years was OR=1.80 (95% CI 1.10-2.96). Four of ten children with eczema at 6 years had the onset of eczema after the age of 2 years, but the co-existence of different allergy-related diseases at 6 years was higher among those with the onset of eczema before 2 years of age.

Conclusions

Although most cases of eczema in the general population were mild to moderate, early eczema was associated with an increased risk of developing childhood asthma. These findings support the hypothesis of an atopic march in the general population.

Trial registration

The Prevention of Allergy among Children in Trondheim study has been identified as ISRCTN28090297 in the international Current Controlled Trials database

Costs of allergic diseases from birth to two years in Finland

OBJECTIVES

Costing studies are needed to identify the resources used for treatment and inform payers of the costs incurred. The objectives were to determine the costs of diagnosing and treating atopic dermatitis, food allergy and asthma, and to compare the share of costs to society and to the family during the first two years of life.

STUDY DESIGN

The data were obtained from an ongoing mother-infant nutrition study. The sample comprised 60 infants who developed allergic disease by the age of 24 months and 56 healthy infants with no allergic disease.

METHODS

The costs included diagnosis and treatment of the allergy, disability allowances, travel expenses and time spent by parents.

RESULTS

The median costs per infant were €275 (range 94-1306) for atopic dermatitis, €1408 (163-5408) for asthma, €3182 (628-11195) for food allergy, and €10 (0-619) for the healthy infants due to the suspicion of allergic disease. The highest costs in atopic dermatitis were caused by primary care visits, topical treatments, travel costs and parents' time, and those for food allergy by hospital out-patient care, infant formulae for cow's milk allergy, disability allowances and travel costs. The families paid 43% of the costs arising from atopic dermatitis, 13.6% of those from food allergy and 16.5% of those from asthma.

CONCLUSIONS

Cow's milk allergy emerged as the most expensive allergic disease, especially for the society, and concurrent asthma in particular further increased the costs.

Does eczema in infancy cause hay fever, asthma, or both in childhood? Insights from a novel regression model of sibling data

BACKGROUND

The atopic march hypothesis proposes that eczema precedes the development of asthma and allergic rhinitis.

OBJECTIVE

We sought to assess the evidence for a causal effect of infantile eczema on childhood hay fever, asthma, or both.

METHODS

We used parental reports on infantile eczema and childhood asthma and hay fever for 3778 pairs of 7-year-olds matched to their sibling closest in age within 2 years from the Tasmanian Longitudinal Health Study. We analyzed paired sibling data using a logistic regression model that allowed inference about a causal effect of a familial predictor on a child's outcome by examining the change in association with their cosibling's predictor after adjusting for their own predictor status.

RESULTS

Siblings were concordant for infantile eczema (tetrachoric correlation, 0.40). For having both hay fever and asthma by age 7 years, the association with cosibling's eczema was an odds ratio (OR) of 1.98 (95% CI, 1.37-2.86), which reduced after adjusting for own eczema to an OR of 1.65 (95% CI, 1.17-2.34). For having hay fever only, the association with cosibling's eczema was an OR of 1.68 (95% CI, 1.22-2.31) before and an OR of 1.59 (95% CI, 1.19-2.14) after adjusting for own eczema. There was no association between having asthma only and cosibling's eczema (OR, 1.00; 95% CI, 0.77-1.30).

CONCLUSIONS

Eczema in infancy might have a causal effect on hay fever in children with and perhaps without asthma. The association of infantile eczema on asthma in children without hay fever, which might be early transient wheeze, is unlikely to be causal or familial. These findings have implications for hay fever prevention.

Markers of oxidative stress are increased in exhaled breath condensates of children with atopic dermatitis

BACKGROUND

Airway inflammation may be present in subjects affected by atopic dermatitis (AD) but still without asthma symptoms. Exhaled breath condensate (EBC) reflects the composition of bronchoalveolar extracellular lining fluid that contains a large number of mediators of airway inflammation and oxidative damage.

OBJECTIVES

  We assessed inflammatory markers in the EBC of patients with AD. Fifty-six children (34 girls and 22 boys) were enrolled: 33 affected by AD and 23 healthy controls.

METHODS

  EBC was collected using a condenser device. We measured EBC pH and concentrations of leukotriene B4 (LTB4), 8-isoprostane, H(2) O(2) , malondialdehyde and 4-hydroxynoneal. Respiratory resistance was also evaluated.

RESULTS

  EBC pH in patients with AD was significantly lower than in healthy children, median (range) being 8·02 (7·94-8·12) in AD vs. 8·11 (8·05-8·16) (P = 0·02). The values of exhaled 8-isoprostane and LTB4 were significantly increased in subjects with AD compared with normal controls (P < 0·01 and P < 0·001, respectively). There was increased 4-hydroxynoneal in patients with AD but this did not reach statistical significance. Evaluating respiratory resistance, no bronchoreversibility was demonstrated in the children with AD.

CONCLUSIONS

pH, LTB4 and 8-isoprostane in EBC could be sensitive markers of airway inflammation in children with AD. Prospective studies would be of interest to evaluate if airway inflammation, not yet clinically evident, could predict the development of asthma later in life in children with AD.

Management of patients with atopic dermatitis: the role of emollient therapy

Atopic dermatitis is a common inflammatory skin disorder that afflicts a growing number of young children. Genetic, immune, and environmental factors interact in a complex fashion to contribute to disease expression. The compromised stratum corneum found in atopic dermatitis leads to skin barrier dysfunction, which results in aggravation of symptoms by aeroallergens, microbes, and other insults. Infants—whose immune system and epidermal barrier are still developing—display a higher frequency of atopic dermatitis. Management of patients with atopic dermatitis includes maintaining optimal skin care, avoiding allergic triggers, and routinely using emollients to maintain a hydrated stratum corneum and to improve barrier function. Flares of atopic dermatitis are often managed with courses of topical corticosteroids or calcineurin inhibitors. This paper discusses the role of emollients in the management of atopic dermatitis, with particular emphasis on infants and young children.

The persistence of atopic dermatitis and filaggrin (FLG) mutations in a US longitudinal cohort

BACKGROUND

Atopic dermatitis (AD) is a common skin disease that is characterized by recurrent episodes of itching. Filaggrin (FLG) loss-of-function (FLG null) mutations have been associated with an increased risk of AD.

OBJECTIVE

We sought to evaluate the effect of individual FLG null mutations on the persistence of AD over time.

METHODS

We evaluated a multiyear prospective cohort study of children with AD with respect to FLG null mutations (R501X, 2282del4, R2447X, and S3247X). We evaluated the association of these mutations with the persistence of AD symptoms over time with respect to reports of no symptoms of AD and whether topical medication was needed for symptom resolution.

RESULTS

Eight hundred fifty-seven subjects were followed for 3684 person-years. One or more FLG null mutations were noted in 16.3% of subjects and specifically in 27.5% of white subjects and 5.8% of African American subjects. Subjects with an FLG null mutation were less likely (odds ratio [OR], 0.54; 95% CI, 0.41-0.71) to report that their skin was symptom free at any time compared with those without an FLG null mutation. The effect of these mutations was similar in white subjects (OR, 0.42; 95% CI, 0.31-0.57) and African-American subjects (OR, 0.53; 95% CI, 0.25-1.12; P = .62). Children with the R501X mutation (OR, 0.44; 95% CI, 0.22-0.88) were the least responsive to therapy.

CONCLUSIONS

In a US cohort with AD, FLG null mutations were common. Children with FLG null mutations were more likely to have persistent AD. Although these mutations were more common in those of European ancestry, their effect on persistence was similar in those of African ancestry. Response to therapy was not uniform among children with FLG null mutations.

Atopic dermatitis: a candidate for disease-modifying strategy

The concept of disease modification has been introduced to define the therapeutic strategies aimed to break, stop, or reverse the natural course of a chronic invalidating disease. This strategy is tightly related to the biomarker-based stratification of affected patients using genetic and other biological markers. With regard to the progress in understanding the genetic background of atopic dermatitis (AD), its natural history and its pivotal role in the emergence of allergic asthma, the time is mature to foster the research field of biomarkers in AD and to consider the elaboration of disease-modifying strategies in the management of AD with the goal to stop or even reverse the atopic march.

Eczema in early childhood is strongly associated with the development of asthma and rhinitis in a prospective cohort

Background

This study aimed to estimate the association between eczema in early childhood and the onset of asthma and rhinitis later in life in children.

Methods

A total of 3,124 children aged 1–2 years were included in the Dampness in Building and Health (DBH) study in the year 2000, and followed up 5 years later by a parental questionnaire based on an International Study of Asthma and Allergies in Childhood protocol. The association between eczema in early childhood and the incidence of asthma and rhinitis later in life was estimated by univariable and multivariable logistic regression modelling.

Results

The prevalence of eczema in children aged 1–2 years was 17.6% at baseline. Children with eczema had a 3-fold increased odds of developing asthma (adjusted odds ratio [aOR], 3.07; 95% confidence interval (CI) 1.79–5.27), and a nearly 3-fold increased odds of developing rhinitis (aOR, 2.63; 1.85–3.73) at follow-up compared with children without eczema, adjusted for age, sex, parental allergic disease, parental smoking, length of breastfeeding, site of living, polyvinylchloride flooring material, and concomitant allergic disease. When eczema was divided into subgroups, moderate to severe eczema (aOR, 3.56; 1.62–7.83 and aOR, 3.87; 2.37–6.33, respectively), early onset of eczema (aOR, 3.44; 1.94–6.09 and aOR, 4.05; 2.82–5.81; respectively), and persistence of eczema (aOR, 5.16; 2.62–10.18 and aOR, 4.00; 2.53–6.22, respectively) further increased the odds of developing asthma and rhinitis. Further independent risk factors increasing the odds of developing asthma were a parental history of allergic disease (aOR, 1.83; 1.29–2.60) and a period of breast feeding shorter than 6 months (aOR, 1.57; 1.03–2.39). The incidence of rhinitis was increased for parental history of allergic disease (aOR, 2.00; 1.59–2.51) and polyvinylchloride flooring (aOR, 1.60; 1.02–2.51).

Conclusion

Eczema in infancy is associated with development of asthma and rhinitis during the following 5-year period, and eczema is one of the strongest risk factors. Early identification is valuable for prediction of the atopic march.

Retrospective analysis of the natural history of atopic dermatitis occurring in the first year of life in Korean children

The aim of this study was to analyze the natural history of atopic dermatitis (AD) and the risk factors associated with the remission of AD in Korean children. We enrolled 597 children with AD that occurred in the first year of life. A variety of factors influencing the prognosis were assessed by medical records and telephone interviews. Their outcome was classified into complete remission, intermittent, and persistent AD. AD had completely disappeared in 422 cases (70.6%), while 149 (25%) and 26 cases (4.4%) showed intermittent and persistent skin symptoms, respectively. The average healing time was 29.6 months in complete remission group and expected healing time of the AD was 60 months. None of risk factors were significant by multivariate analysis. But, in moderate-to-severe AD group, maternal diet restriction during lactation (P = 0.046) and no sensitization to cow's milk (P = 0.017) were significantly associated with remission of AD in the multivariate analysis. In conclusion, AD occurring in the first year of life disappears in a significant proportion of patients. In addition, in Korean children with moderate-to-severe AD, maternal diet restriction of allergenic food during lactation and sensitization to cow's milk seem to predict the prognosis of AD.

Plasma adrenomedullin levels in children with asthma: any relation with atopic dermatitis?

BACKGROUND

Asthma is a chronic, inflammatory disease of the airway, and adrenomedullin (ADM) may have some effects against bronchoconstriction. However, the role(s) of ADM in asthmatic children have not been evaluated yet. The aims of this study were to determine if there are any changes in plasma ADM levels during acute asthma attack, and to search for any association between allergen sensitivity and ADM level in asthmatic children.

METHODS

Twenty-seven children with acute asthma attack, ranging in age from 5 to 15 years were investigated and compared with 20 controls. Plasma ADM levels (ng/mL) were measured by ELISA method.

RESULTS

No significant difference was found in ADM levels between the controls and patients in either the acute attack or remission period. Plasma ADM levels were significantly higher in the acute attack (p=0.043) compared to the remission period in patients who were considered as having a "severe attack" according to GINA (Global Initiative for Asthma) classification. There were statistically significant correlations between the patients' AlaTOP and Food Panel 7 levels and plasma ADM levels in the acute attack period (p=0.010, p=0.001, respectively). The ADM levels in patients with a history of atopic dermatitis were significantly higher in the acute attack period compared to those without a history of atopic dermatitis (p=0.007).

CONCLUSION

We speculate that ADM may have a role in children with atopic dermatitis, and may also have a role in the immuno-inflammatory process of asthma.

Nutrition Economic Evaluation of Allergy Treatment in Infants and Children: background for probiotic studies

The treatment of food allergy is based on avoidance of the foods, which cause symptoms, and their replacement with nutritionally comparable foods. The cost of food allergy and elimination diets to families and society is poorly known. Our results suggest that estimation of dietary costs on the basis of dietary records was possible but challenging. In infancy, cost differences were small but vary depending on the age group with the reduction of median yearly costs around 180–240€. Thus, further studies are required for a more accurate cost estimate and an estimation of the impact of specific probiotics.

Association of variants in innate immune genes with asthma and eczema

BACKGROUND

The innate immune pathway is important in the pathogenesis of asthma and eczema. However, only a few variants in these genes have been associated with either disease. We investigate the association between polymorphisms of genes in the innate immune pathway with childhood asthma and eczema. In addition, we compare individual associations with those discovered using a multivariate approach.

METHODS

Using a novel method, case control based association testing (C2BAT), 569 single nucleotide polymorphisms (SNPs) in 44 innate immune genes were tested for association with asthma and eczema in children from the Boston Home Allergens and Asthma Study and the Connecticut Childhood Asthma Study. The screening algorithm was used to identify the top SNPs associated with asthma and eczema. We next investigated the interaction of innate immune variants with asthma and eczema risk using Bayesian networks.

RESULTS

After correction for multiple comparisons, 7 SNPs in 6 genes (CARD25, TGFB1, LY96, ACAA1, DEFB1, and IFNG) were associated with asthma (adjusted p-value<0.02), while 5 SNPs in 3 different genes (CD80, STAT4, and IRAKI) were significantly associated with eczema (adjusted p-value < 0.02). None of these SNPs were associated with both asthma and eczema. Bayesian network analysis identified 4 SNPs that were predictive of asthma and 10 SNPs that predicted eczema. Of the genes identified using Bayesian networks, only CD80 was associated with eczema in the single-SNP study. Using novel methodology that allows for screening and replication in the same population, we have identified associations of innate immune genes with asthma and eczema. Bayesian network analysis suggests that additional SNPs influence disease susceptibility via SNP interactions.

CONCLUSION

Our findings suggest that innate immune genes contribute to the pathogenesis of asthma and eczema, and that these diseases likely have different genetic determinants.

ST2 requires Th2-, but not Th17-, type airway inflammation in epicutaneously antigen- sensitized mice

BACKGROUND

IL-33 is known to induce Th2-type cytokine production by various types of cells through its receptors, ST2 and IL-1RAcP. Polymorphism in the ST2 and/or IL-33 genes was found in patients with atopic dermatitis and asthma, implying that the IL-33/ST2 pathway is closely associated with susceptibility to these diseases. Exposure to allergens through damaged skin is suspected to be a trigger for allergen sensitization, resulting in development of such allergic disorders as asthma and atopic dermatitis.

METHODS

To elucidate the role(s) of the IL-33/ST2 pathway in asthma in individuals who had been epicutaneously sensitized to an antigen, wild-type and ST2-/- mice were epicutaneously sensitized with ovalbumin (OVA) and then were intranasally challenged with OVA. The degree of airway inflammation, the number of leukocytes and the activities of myeloperoxidase (MPO) and eosinophil peroxidase (EPO) in bronchoalveolar lavage fluids (BALFs), The levels of cytokines and chemokines in lungs and OVA-specific IgE levels in sera were determined by histological analysis, a hemocytometer, colorimetric assay, quantitative PCR or ELISA, respectively.

RESULTS

The number of eosinophils in BALFs, the levels of Th2 cytokines and chemoattractants in the lungs and OVA-specific IgE in sera from ST2-/- mice were significantly reduced compared with wild-type mice. Although the number of neutrophils in BALFs and the pulmonary levels of IL-17 were comparable in both mice, the levels of MPO activity in BALFs and neutrophil chemoattractants in the lung were reduced in ST2-/- mice.

CONCLUSIONS

The IL-33/ST2 pathway is crucial for Th2-cytokine-mediated eosinophilic, rather than Th17-cytokine-mediated neutrophilic, airway inflammation in mice that had been epicutaneously sensitized with antigens and then challenged with antigen.

Presentation of atopic disease in a large cohort of pediatric liver transplant recipients

Atopic disease occurs in solid organ transplant recipients with an increasingly recognized frequency. The time course for the development of these atopic diseases in liver transplantation has not been described. The objective was to characterize the atopic manifestations of children receiving chronic immunosuppression after orthotopic liver transplantation (OLT). Chart review and follow-up questionnaire were utilized for 176 OLT pediatric recipients at a single institution for manifestations of allergic disease. Atopic disease was present in 25 (14.2%) patients. Median age at transplant was 16 months with a median follow-up of 63 months. Food allergy and non-food related atopic symptoms presented at a median of 11.5 (IQR, 6-28) and 19 (IQR, 5-41) months post-transplantation, respectively. The median age at transplant of the non-atopic children was 72 months, higher than patients with atopy (p < 0.001). Food allergy and atopic skin disease symptoms were present in 40% and 56% of cases, respectively. Asthma, allergic rhinitis, or both were found in 66% of cases. The onset of symptoms of food allergy and eczema (median, 12 months post-transplantation) preceded symptoms of allergic rhinitis and asthma. (median of 27 and 30 months post-transplantation, respectively). Atopy occurs in ∼14% of pediatric liver transplant recipients, with manifestations including food allergy, eczema, allergic rhinitis, and asthma.

Filaggrin mutations and atopy: consequences for future therapeutics

Filaggrin is a key component of the epidermal differentiation complex of the stratum corneum in the epidermal layer of human skin. Loss-of-function mutations in filaggrin have been described in patients with atopic eczema and are associated with an increased risk of atopic sensitization in these individuals. Atopic eczema is the first stage of the atopic march that describes the phenomenon of increased rates of allergic rhinitis and allergic asthma observed in individuals with early atopic dermatitis. The skin barrier disruptions of atopic eczema associated with loss-of-function mutations in filaggrin are thought to provide a nidus for allergic sensitization to food and aeroallergens, which can then lead to increased allergic disease. It is on this foundation that therapies aimed at restoration of barrier function are thought to play a role, not only in the effective treatment of atopic eczema, but also in the prevention of further allergic disease development.

Homeopathy in paediatric atopic diseases: long-term results in children with atopic dermatitis

AIM

To study the socio-demographic features, the prescribed remedies and the outcome of atopic diseases in children treated with homeopathy at the Homeopathic Clinic of Lucca (Italy), and the long-term outcome of children suffering from atopic dermatitis (AD) after an approximate 8-year period (range 5-10 years).

METHODS

Our data derive from an observational longitudinal study carried out on 213 children (38.6%) with atopic diseases out of 551 children consecutively examined from September 1998 to December 2008. We used the Glasgow Homeopathic Hospital Outcome Score to evaluate the results that were classified on the basis of a Likert scale.

RESULTS

Eighty-three (39%) children were affected by asthma, 51 (24%) by allergic rhinoconjunctivitis, 76 (36%) by AD and 3 (1%) by food intolerance. Follow-up patients were 104 (48.8%), and 65 (62.5%) of them reported a major improvement or resolution. The parents of paediatric patients suffering from AD, who had started homeopathic treatment at <4.9 years of age were invited to follow-up assessment 8 years later and 40 children (mean age 12.9) were examined; 28/40 (70%) had a complete disappearance of AD, 12/40 children (30.0%) were still affected by AD; 8/40 (20%) had asthma and 8/40 patients had, or developed, allergic rhinitis.

CONCLUSION

These preliminary results seem to confirm a positive therapeutic effect of homeopathy in atopic children. Furthermore, according to the data from the literature paediatric patients treated with homeopathy seem to show a reduced tendency to maintain AD and develop asthma (and allergic rhinitis) in adult age.

Effect of cat and daycare exposures on the risk of asthma in children with atopic dermatitis

Atopic dermatitis (AD) in young children is often followed by the development of asthma (atopic march). The role of environmental exposures is unclear in this high-risk population. We aimed to determine the predictive relationship between indoor allergen exposures, particularly pets, rodents, and cockroaches, to the development of asthma in a prospective pediatric cohort. Children with AD and a family history of allergy were followed prospectively with questionnaire ascertainment of environmental exposure to cats, dogs, cockroaches, rats, and mice. Asthma was diagnosed by study physicians based on caregiver reports of symptoms continually assessed over the course of the study period. Fifty-five of the 299 children developed asthma by the end of the study. Cat exposure had a strong and independent effect to reduce the risk of developing asthma across all analyses (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.05-0.53). Dog, mouse, rat, and cockroach exposures did not significantly influence the development of asthma. Daycare exposure had the largest risk reduction for the development of asthma (OR, 0.08; 95% CI, 0.03-0.19). Maternal asthma (OR, 2.93; 95% CI, 1.29-6.67), baseline body mass index (OR, 1.23; 95% CI, 1.08-1.42), and specific immunoglobulin E to house-dust mix at 3 years were each independent risk factors for the development of asthma. In children with AD, cat and daycare exposure may reduce the risk of developing early childhood asthma.

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.

Particular characteristics of allergic symptoms in tropical environments: follow up to 24 months in the FRAAT birth cohort study

Background

Early wheezing and asthma are relevant health problems in the tropics. Mite sensitization is an important risk factor, but the roles of others, inherent in poverty, are unknown. We designed a birth-cohort study in Cartagena (Colombia) to investigate genetic and environmental risk factors for asthma and atopy, considering as particular features perennial exposure to mites, parasite infections and poor living conditions.

Methods

Pregnant women representative of the low-income suburbs of the city were randomly screened for eligibility at delivery; 326 mother-infant pairs were included at baseline and biological samples were collected from birth to 24 months for immunological testing, molecular genetics and gene expression analysis. Pre and post-natal information was collected using questionnaires.

Results

94% of families were from the poorest communes of the city, 40% lacked sewage and 11% tap-water. Intestinal parasites were found as early as 3 months; by the second year, 37.9% of children have had parasites and 5.22% detectable eggs of Ascaris lumbricoides in stools (Median 3458 epg, IQR 975-9256). The prevalence of "wheezing ever" was 17.5% at 6 months, 31.1% at 12 months and 38.3% at 24 months; and recurrent wheezing (3 or more episodes) 7.1% at 12 months and 14.2% at 24 months. Maternal rhinitis [aOR 3.03 (95%CI 1.60-5.74), p = 0.001] and male gender [aOR 2.09 (95%CI 1.09 - 4.01), p = 0.026], increased risk for wheezing at 6 months. At 24 months, maternal asthma was the main predisposing factor for wheezing [aOR 3.65 (95%CI 1.23-10.8), p = 0.01]. Clinical symptoms of milk/egg allergy or other food-induced allergies were scarce (1.8%) and no case of atopic eczema was observed.

Conclusions

Wheezing is the most frequent phenotype during the first 24 months of life and is strongly associated with maternal asthma. At 24 months, the natural history of allergic symptoms is different to the "atopic march" described in some industrialized countries. This cohort is representative of socially deprived urban areas of underdeveloped tropical countries. The collection of biological samples, data on exposure and defined phenotypes, will contribute to understand the gene/environment interactions leading to allergy inception and evolution.

Cost-effectiveness model for a specific mixture of prebiotics in The Netherlands

The objective of this study was to assess the cost-effectiveness of the use of prebiotics for the primary prevention of atopic dermatitis in The Netherlands. A model was constructed using decision analytical techniques. The model was developed to estimate the health economic impact of prebiotic preventive disease management of atopic dermatitis. Data sources used include published literature, clinical trials and official price/tariff lists and national population statistics. The comparator was no supplementation with prebiotics. The primary perspective for conducting the economic evaluation was based on the situation in The Netherlands in 2009. The results show that the use of prebiotics infant formula (IMMUNOFORTIS(®)) leads to an additional cost of € 51 and an increase in Quality Adjusted Life Years (QALY) of 0.108, when compared with no prebiotics. Consequently, the use of infant formula with a specific mixture of prebiotics results in an incremental cost-effectiveness ratio (ICER) of € 472. The sensitivity analyses show that the ICER remains in all analyses far below the threshold of € 20,000/QALY.

CONCLUSION

This study shows that the favourable health benefit of the use of a specific mixture of prebiotics results in positive short- and long-term health economic benefits. In addition, this study demonstrates that the use of infant formula with a specific mixture of prebiotics is a highly cost-effective way of preventing atopic dermatitis in The Netherlands.

Effect of environmental tobacco smoke on atopic dermatitis among children in Korea

The prevalence of atopic dermatitis is increasing in many countries. Several factors are known to be associated with childhood atopic dermatitis. Environmental tobacco smoke (ETS) is one of the most common indoor pollutants, and children are more vulnerable to ETS exposure than adults are. In this study, the possible association of ETS with atopic dermatitis was evaluated in 7030 individuals aged 6-13 years who participated in the Children's Health and Environment Research study. In addition, predictive factors, such as the allergic history of the parents, children's immunoglobulin E levels and children's history of rhinitis and its association with dermatitis, were assessed. After adjustment for possible confounding variables, atopic dermatitis was found to be highly correlated with ETS, especially among children whose mothers had smoked during pregnancy and/or in the first year after birth (OR=2.06, 95% CI: 1.01-4.22). In conclusion, our results show that childhood exposure to ETS is a major risk factor for atopic dermatitis.

Comorbidity in Atopic Dermatitis

The negative impact of atopic dermatitis (AD) often extends beyond the skin. Children with AD experience increased rates of infectious, mental health, and allergic diseases compared to their non-atopic peers. The mechanisms underlying these associations remain elusive. New insights from genetic and epidermal research pinpoint the skin barrier as a primary initiator of AD. Epicutaneous sensitization represents an intriguing new model which links a disrupted skin barrier to the later development of IgE-mediated diseases in patients with AD. Recent epidemiological studies have identified new comorbidities linked to AD as well, including several mental health disorders and obesity. This manuscript reviews the recent literature regarding both classic and newly described AD comorbidities.

Comorbidities between nose and skin allergy

PURPOSE OF REVIEW

This review focuses on comorbidities between nose and skin allergies. For this purpose, allergic rhinitis and chronic rhinosinusitis (CRS) were selected as examples of nasal disorders and atopic dermatitis and urticaria as examples of allergic skin disorders and the individual entities of both localizations were evaluated and compared in relation to their prevalence and coincidence, underlying pathophysiological mechanisms, genetic data and shared therapy options.

RECENT FINDINGS

The inter-relationships between atopic dermatitis and allergic rhinitis are the best studied, but even for the other comorbidities it was possible to demonstrate comparable pathomechanisms in addition to a high prevalence and coincidence, particularly in the case of atopically assisted forms. In this context, the interactions of IgE, mast cells and eosinophils play a special role, but genetic issues, the significance of epithelial barrier defects and colonization with Staphylococcus aureus are also important sharing issues.

SUMMARY

Allergic skin disorders such as atopic dermatitis and urticaria are frequently associated with comorbidities of the nose as well as allergic rhinitis and CRS. By contrast, different manifestations of these diseases involve the nose and the skin. These are not separate diseases but are linked by complex and currently unclear/insufficiently defined inter-relationships.

The relationship of rhinitis and asthma, sinusitis, food allergy, and eczema

Epidemiologic, genetic, immunologic, and clinical studies show a close relationship between allergic rhinitis and asthma, food allergy, and atopic dermatitis. Rhinitis and sinusitis often coexist and are commonly referred to with the term rhinosinusitis. These conditions are also linked in the so-called atopic march, which is the sequential appearance of atopic manifestations starting with atopic dermatitis and later followed by food allergy, allergic rhinitis, and asthma. Allergic rhinitis and asthma are now increasingly being approached diagnostically and therapeutically as the one-airway concept.

The Role of TSLP in IL-13-induced atopic march

Although atopic dermatitis (AD) is the initial step of the “atopic march”, a progression from AD to asthma, the underlying mechanism remains unknown. Selective expression of IL-13 in the skin of mice caused an AD phenotype resembling human AD, and the disorder was associated with enhanced production of thymic stromal lymphopoietin (TSLP) in the AD skin with a systemic Th2 immunity. Here we show that IL-13 transgenic mice with AD had significantly enhanced lung inflammation, mucus hypersecretion, and airway hyperresponsiveness (AHR) when sensitized and challenged by allergen. In addition, the level of TSLP was significantly higher in acute AD than in chronic AD. Furthermore, elimination of TSLP signaling significantly diminished the allergic asthma responses, immune cell production of Th2 cytokines (IL-4, IL-13), and serum IgE. These studies indicate that IL-13 induces AD and atopic march via a TSLP dependent mechanism.

The genetics of asthma and allergic disease: a 21st century perspective

Asthma and allergy are common conditions with complex etiologies involving both genetic and environmental contributions. Recent genome-wide association studies (GWAS) and meta-analyses of GWAS have begun to shed light on both common and distinct pathways that contribute to asthma and allergic diseases. Associations with variation in genes encoding the epithelial cell-derived cytokines, interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP), and the IL1RL1 gene encoding the IL-33 receptor, ST2, highlight the central roles for innate immune response pathways that promote the activation and differentiation of T-helper 2 cells in the pathogenesis of both asthma and allergic diseases. In contrast, variation at the 17q21 asthma locus, encoding the ORMDL3 and GSDML genes, is specifically associated with risk for childhood onset asthma. These and other genetic findings are providing a list of well-validated asthma and allergy susceptibility genes that are expanding our understanding of the common and unique biological pathways that are dysregulated in these related conditions. Ongoing studies will continue to broaden our understanding of asthma and allergy and unravel the mechanisms for the development of these complex traits.

Geographical and sociodemographic risk factors for allergic diseases in korean children

PURPOSE

(a) To examine geographical distribution of childhood allergic diseases in Korea and (b) to identify geographical and sociodemographic risk factors for allergic diseases.

METHODS

Data on doctor-diagnosed asthma during lifetime and allergic rhinitis and atopic dermatitis during the past 12 months of 8,631 children (≤ 18 years) were obtained from the Third Korea National Health and Nutrition Examination Survey, along with information on housing type and presence of an indoor smoker. The SaTScan program identified geographical case clusters of allergic diseases, and multiple logistic regression determined risk factors, including geographical case clusters, for each allergic disease.

RESULTS

Prevalence of asthma, allergic rhinitis, and atopic dermatitis was 3.2%, 13.2%, and 15.5%, respectively. Older children (10-18 years) were more likely to have allergic rhinitis whereas younger children were more likely to have atopic dermatitis. It is noteworthy that children living in areas of geographical risk for asthma and atopic dermatitis were more likely to develop the respective allergic disease than children living in other areas (odds ratio [OR] = 3.47 for asthma, and OR = 9.74 for atopic dermatitis).

CONCLUSIONS

This study indicates that the areas in which children live may influence the development of certain allergic diseases. Implications include the need to assess geographical location of children with allergic diseases and to develop community-based preventive programs for children with allergic diseases.

Childhood eczema and rhinitis predict atopic but not nonatopic adult asthma: a prospective cohort study over 4 decades

BACKGROUND

The evidence on whether the atopic march observed in childhood (ie, the progression from eczema to allergic rhinitis and asthma) extends to adulthood is sparse, and there is no evidence on whether the progression leads to a specific phenotype of asthma.

OBJECTIVE

We sought to assess whether childhood eczema and rhinitis are risk factors for specific phenotypes of adult asthma.

METHODS

Participants of the Tasmanian Longitudinal Health Study recruited in 1968 (age range, 6.0-7.0 years) were followed up at age 44 years. The risk of current atopic or nonatopic asthma in middle age characterized by sensitization to aeroallergens given childhood eczema, rhinitis, or both was calculated by using multinomial logistic regression.

RESULTS

No association was found between childhood eczema or rhinitis and nonatopic adult asthma. In contrast, childhood eczema and rhinitis in combination predicted both new-onset atopic asthma by middle age (adjusted multinomial odds ratio [aMOR], 6.3; 95% CI, 1.7-23.2) and the persistence of childhood asthma to adult atopic asthma (aMOR, 11.7; 95% CI, 3.6-37.9). Participants with childhood eczema alone were at increased risk of new-onset atopic asthma (aMOR, 4.1; 95% CI, 1.9-8.8), whereas rhinitis alone predicted the persistence of childhood asthma to atopic asthma (aMOR, 2.7; 95% CI, 1.3-5.6). Of all asthma, 29.7% of persistent atopic asthma and 18.1% of new-onset atopic asthma could be attributed to having childhood eczema and rhinitis.

CONCLUSION

Childhood eczema and rhinitis are strongly associated with the incidence and persistence of adult atopic asthma.

Epidemiology of atopic dermatitis and atopic march in children

Atopic dermatitis (AD) is one of the most common chronic childhood skin diseases affecting up to 17% of children in the United States. The point prevalence of AD has increased based on validated questionnaires in the most recent update of the International Study of Asthma and Allergies in Childhood. However, the increases are primarily in developing countries, whereas the rates have stabilized in countries with higher incomes. AD starts in early childhood with 65% of children affected by 18 months of age. Furthermore, less than half of the patients with AD have complete resolution by 7 years of age and only 60% have resolution by adulthood, indicating the chronic nature of AD. AD is a major risk factor for the development of asthma, with an increased odds ratio in children with AD in several longitudinal studies compared with children without AD, and about 30% of patients with AD develop asthma. Patients with atopic sensitization along with eczema are at a higher risk for progressing in the atopic march to asthma. The main risk factors for progression and persistence of asthma are early onset and severity of AD.

The atopic march: progression from atopic dermatitis to allergic rhinitis and asthma

Atopic dermatitis (AD) is an inflammatory disease characterized by pruritic skin lesions. The pathogenesis of AD may include disrupted epidermal barrier function, immunodysregulation, and IgE-mediated sensitization to food and environmental allergens. AD is also part of a process called the atopic march, a progression from AD to allergic rhinitis and asthma. This has been supported by multiple cross-sectional and longitudinal studies and experimental data. Research on the mechanisms of AD has been centered on the adaptive immune system with an emphasis on the T-helper 1 (Th1)-Th2 paradigm. Recently, the conceptual focus has largely shifted to include a primary defect in the epithelial barrier as an initial event in AD providing a significant insight into the disease initiation and pointing to a complex secondary interplay of environmental and immunological sequelae with barrier disruption. Further understanding of AD will help the development of more effective treatment for AD and ultimately, preventative algorithms for the atopic march. In this review we highlight recent advances in our understanding of the pathogenesis of AD and the atopic march.

Effects of prenatal and perinatal exposure to fine air pollutants and maternal fish consumption on the occurrence of infantile eczema

BACKGROUND

As there is a scarcity of evidence on potential hazards and preventive factors for infantile eczema operating in the prenatal period, the main goal of this study was to assess the role of prenatal exposure to fine particulate matter and environmental tobacco smoke (ETS) in the occurrence of infant eczema jointly with the possible modulating effect of maternal fish consumption.

METHODS

The study sample consisted of 469 women enrolled during pregnancy, who gave birth to term babies (>36 weeks of gestation). Among all pregnant women recruited, personal measurements of fine particulate matter (PM₂.₅) were performed over 48 h in the second trimester of pregnancy. After delivery, every 3 months in the first year of the newborn's life, a detailed, standardized, face-to-face interview was administered to each mother, in the process of which a trained interviewer recorded any history of infantile eczema and data on potential environmental hazards. The estimated risk of eczema related to higher prenatal exposure to fine particulate matter (PM₂.₅ > 53.0 μg/m³) and postnatal ETS as well as the protective effect of maternal fish intake were adjusted for potential confounders in a multivariable logistic regression model.

RESULTS

While the separate effects of higher prenatal PM₂.₅ and postnatal ETS exposure were not statistically significant, their joint effect appeared to have a significant influence on the occurrence of infantile eczema [odds ratio 2.39, 95% confidence interval (CI) 1.10-5.18]. With maternal fish intake of more than 205 g/week, the risk of eczema decreased by 43% (odds ratio 0.57, 95% CI 0.35-0.93). The incidence rate ratio (IRR) for eczema symptoms, estimated from the Poisson regression model, was increased with both higher exposure to prenatal PM₂.₅ and postnatal ETS (IRR 1.55, 95% CI 0.99-2.44) and in children of atopic mothers (IRR 1.35, 95% CI 1.04-1.75) but was lower in girls (IRR 0.78, 95% CI 0.61-1.00). The observed preventive effect of fish consumption on the frequency of eczema symptoms was consistent with the results of the logistic analysis (IRR 0.72, 95% CI 0.52-0.99).

CONCLUSIONS

The findings indicate that higher prenatal exposure to fine particulate matter combined with postnatal exposure to ETS may increase the risk of infant eczema, while maternal fish intake during pregnancy may reduce the risk of infantile eczema.

Tree nut allergy, egg allergy, and asthma in children

BACKGROUND

Children with food allergies often have concurrent asthma.

OBJECTIVE

The authors aimed to determine the prevalence of asthma in children with food allergies and the association of specific food allergies with asthma.

METHODS

Parental questionnaire data regarding food allergy, corroborated by allergic sensitization were completed for a cohort of 799 children with food allergies. Multivariate regression analysis tested the association between food allergy and reported asthma.

RESULTS

In this cohort, the prevalence of asthma was 45.6%. After adjusting for each food allergy, environmental allergies, and family history of asthma, children with egg allergy (odds ratio [OR] = 2.0; 95% confidence interval [CI] = 1.3-3.2; P < .01) or tree nut allergy (OR = 2.0; 95% CI = 1.1-3.6; P = .02) had significantly greater odds of report of asthma.

CONCLUSION

There is a high prevalence of asthma in the food-allergic pediatric population. Egg and tree nut allergy are significantly associated with asthma, independent of other risk factors.

Synbiotics prevent asthma-like symptoms in infants with atopic dermatitis

BACKGROUND

  Infants with atopic dermatitis (AD) have a high risk of developing asthma. We investigated the effect of early intervention with synbiotics, a combination of probiotics and prebiotics, on the prevalence of asthma-like symptoms in infants with AD.

METHODS

  In a double-blind, placebo-controlled multicentre trial, ninety infants with AD, age <7\ months, were randomized to receive an extensively hydrolyzed formula with Bifidobacterium breve M-16V and a galacto/fructooligosaccharide mixture (Immunofortis(®) ), or the same formula without synbiotics during 12 weeks. After 1 year, the prevalence of respiratory symptoms and asthma medication use was evaluated, using a validated questionnaire. Also, total serum IgE and specific IgE against aeroallergens were determined.

FINDINGS

  Seventy-five children (70.7% male, mean age 17.3 months) completed the 1-year follow-up evaluation. The prevalence of 'frequent wheezing' and 'wheezing and/or noisy breathing apart from colds' was significantly lower in the synbiotic than in the placebo group (13.9%vs 34.2%, absolute risk reduction (ARR) -20.3%, 95% CI -39.2% to -1.5%, and 2.8%vs 30.8%, ARR -28.0%, 95% CI -43.3% to -12.5%, respectively). Significantly less children in the synbiotic than in the placebo group had started to use asthma medication after baseline (5.6%vs 25.6%, ARR -20.1%, 95% CI -35.7% to -4.5%). Total IgE levels did not differ between the two groups. No children in the synbiotic and five children (15.2%) in the placebo group developed elevated IgE levels against cat (ARR -15.2%, 95% CI -27.4% to -2.9%).

CONCLUSION

  These results suggest that this synbiotic mixture prevents asthma-like symptoms in infants with AD.

Food allergy and atopic dermatitis: separating fact from fiction

The relationship between food and atopic dermatitis (AD) is complex. A common misunderstanding is that food allergies have a significant impact on the course of AD, resulting in uncontrolled attempts at elimination diets and undertreatment of the skin itself. Studies have shown that only a small portion of cutaneous reactions to food in the form of late, eczematous eruptions will directly exacerbate AD in young infants who have moderate-to-severe AD. Given the low frequency of food allergies actually inducing flares of AD, the focus should return to appropriate skin therapy, and identification of true food allergies should be reserved for recalcitrant AD in children in whom the suspicion for food allergy is high. A different relationship between food and AD involves delaying or preventing AD in high-risk infants by exclusive breastfeeding during the first 4 months of life. Finally, the skin barrier defect in AD may allow for easier and earlier sensitization of food and airborne allergens; therefore, exposure of food proteins on AD skin may act as a risk factor for development of food allergies.

Allergic rhinitis: indicators of quality of life

The objective of this review was to present evidence of the relationship between allergic rhinitis and impairment of quality of life. The data sources were original articles, reviews and consensus statements entered into the Medline and LILACS databases between 1997 and 2008. The following search terms were used: 'allergic rhinitis'; 'quality of life'; and 'sleep disorders'. Quality of life is often impaired in patients with allergic rhinitis, due to the classic symptoms of the disease (sneezing, pruritus, rhinorrhea and nasal obstruction). In addition, the pathophysiology of allergic rhinitis often disrupts sleep, leading to fatigue, irritability, memory deficits, daytime sleepiness and depression. The total burden of this disease goes beyond impairment of physical and social functioning. It has also a financial impact, which becomes greater when we consider the evidence that allergic rhinitis is a possible causal factor of comorbidities, such as asthma and sinusitis. Nasal obstruction, the most prominent symptom, is associated with sleep disorders, which can have a profound effect on mental health, learning, behavior and attention. Finally, allergic rhinitis-a chronic condition that affects adults, adolescents and children-is often underdiagnosed or inadequately treated. The deleterious impact that allergic rhinitis-related sleep disorders have on patient capacity to perform activities of daily living is an important component of the morbidity of the disease. With an accurate diagnosis, there are various available treatments that can reduce the burden of allergic rhinitis.

The patient with allergies

Allergic disease affects a sizeable percentage of the general population, has a significant impact on patient quality of life, and exerts a significant financial burden on society. Atopic symptoms from inhalant allergens are among the most frequent complaints in outpatient medical visits. Key history and physical examination findings help to distinguish allergic rhinitis from other forms of chronic rhinosinusitis. Diagnostic testing may not be necessary unless immunotherapy is contemplated.

Does improvement management of atopic dermatitis influence the appearance of respiratory allergic diseases? A follow-up study

Background

Atopic dermatitis (AD) is often the prelude to allergic diseases. The aim of this study was 1) to evaluate if an integrated management regime could bring about a change in the evolution of the disease in comparison to the results of a previous study; 2) to determine whether the refinement of allergic investigations allowed to identify more promptly the risk factors of evolution into respiratory allergic diseases.

Methods

The study included 176 children affected by AD and previously evaluated between 1993 and 2002 at the age of 9-16 months, who underwent a telephonic interview by means of a semi-structured, pre-formed questionnaire after a mean follow-up time of 8 years. According to the SCORAD, at first evaluation children had mild AD in 23% of cases, moderate in 62%, severe in 15%.

Results

AD disappeared in 92 cases (52%), asthma appeared in 30 (17%) and rhinoconjunctivitis in 48 (27%). The factors significantly related to the appearance of asthma were: sensitization to food allergens with sIgE > 2 KU/L (cow's milk and hen's egg; P < 0.05); to inhalant allergens with sIgE > 0.35 KU/L (P < 0.05). Logistic regression analysis showed that inhalant sensitization was positively related to the occurrence of asthma (OR = 4.219). While AD showed similar rates of disappearance to those of our previous study, the incidence of asthma was reduced, at the same follow-up time, from 29% to 15% (P = 0.002), and the incidence of rhinoconjunctivitis from 35% to 24% (P = 0.02).

Conclusion

Comparing the results with those of the previous study, integrated management of AD does not seem to influence its natural course. Nevertheless, the decrease in the percentage of children evolving towards respiratory allergic disease stresses the importance of early diagnosis and improvement management carried out by specialist centers. The presence of allergic sensitization at one year of age might predict the development of respiratory allergy.

Impact of comorbidities on asthma

Asthma is a common and serious illness with suboptimal outcomes of care. Epidemiological studies show certain comorbidities occurring more frequently than expected with asthma, with some being associated with poor control and a differential response to therapy options. This review summarizes the evidence of clinically important comorbidities, focusing on the best-explored conditions, including rhinitis and rhinosinusitis, anxiety and depression, obesity, gastroesophageal reflux, smoking and dysfunctional breathing. The evidence of epidemiological and pathophysiological associations for these comorbidities is explored, and the practical therapeutic implications are considered. Comorbidities are important for clinicians treating asthma as they may be markers of patients at risk of poor outcomes, they may point to specific effective treatment options and they are important to researchers as possible confounding factors in clinical trials.