Childhood Asthma Prevention Research Articles

Predictors for snoring in children with rhinitis at Age 5

Snoring is often found in allergic diseases and may be an early manifestation of more serious sleep-disordered breathing. We aimed to investigate whether the risk factors for snoring among pre-school children with rhinitis are similar to those for allergic diseases in a birth cohort. The study cohort was drawn from participants in the Childhood Asthma Prevention Study (CAPS). This is a randomized controlled trial of dietary intervention and house dust mite avoidance during the first 5 years of life, aimed at reducing the risk of acquiring asthma and other allergic conditions in children at high-risk for allergic diseases. Parents of children with symptoms of rhinitis at age 5 years (n = 219 out of 516 cohort members) were asked if their child snored: 127 (60%) reported some snoring and 56 (26%) snored more than three times per week. Multiple logistic regression analyses indicated that children who were first-born (adjusted odds ratio, 2.50, 95% CI 1.20-5.21), were exposed to maternal tobacco smoke during the first year of life (2.40, 1.1-5.25), or who had asthma (2.51, 1.14-5.55) and/or eczema (2.29, 1.02-5.13) at age 5 years were more likely to snore. Birth-weight, body mass index at age 4.5, spirometry, and breastfeeding were not related to snoring. Risk factors for snoring are similar to risk factors for allergic disorders. Snoring may be part of the allergic spectrum of diseases. Our data may contribute to clinician's ability to effectively screen for snoring in preschool children.

Infant growth modelling using a shape invariant model with random effects

Models for infant growth have usually been based on parametric forms, commonly an exponential or similar model, which have been shown to fit poorly especially during the first year of life. An alternative approach is to use a non-parametric model, based on a shape invariant model (SIM), where a single function is transformed by shifting and scaling to fit each subject. In the model a regression spline is used as the function, with log transformation of the data and a simplification of the SIM, obtained from the relationship with the exponential model. All subjects are fitted as a nonlinear mixed effects model, allowing the variation in the parameters between subjects to be determined. Methods for the inclusion of covariates in growth models based on SIM are developed, with parameters for time independent covariates included in the model by varying either the shape, the size parameter or the growth parameter and time-dependent co-variates included by transforming the time axis, to either increase or decrease the growth rate dependent on the co-variate, similar to methods used for accelerated failure-time models. The model is used to fit weight data for 602 infants, measured from 0 to 2 years as part of the Childhood Asthma Prevention Study (CAPS) trial, and to determine the effect of breastfeeding on infant weight.

Is there any role for allergen avoidance in the primary prevention of childhood asthma?

In this article we discuss 3 hypotheses to attempt to understand why preventive measures thus far studied with the aim of preventing (or delaying) the development of asthma have shown such disappointing results. The most likely explanation is that the development of a multifactorial disease, such as asthma, is extremely difficult, if not impossible, to prevent by eliminating only one risk factor. In a meta-analysis we investigated the effect of a multifaceted and monofaceted intervention in 10 prospective birth cohorts of a total of 3473 children on a diagnosis of asthma. Multifaceted intervention studies had an odds ratio (OR) of 0.73 (95% CI, 0.55-0.97), whereas the monointervention studies had an OR of 1.22 (95% CI, 0.83-1.78) in patients younger than 5 years and an OR of 0.52 (95% CI, 0.32-0.84) versus 0.93 (95% CI, 0.66-1.31) in patients older than 5 years. We therefore hypothesize that studies with a multifaceted approach will have a much greater chance of being successful than studies using a monofaceted approach, with the latter being unlikely to yield a clinically relevant reduction of asthma.

Prevention of asthma in childhood

The prevalence of asthma is increasing in many parts of the world, particularly in developed countries. The present review focuses on recent literature regarding asthma prevention in childhood. Several environmental exposures in infancy or early childhood are associated with reduced prevalence of asthma, but the mechanisms leading to these associations remain unknown. Recent studies have demonstrated limited success in the prevention of asthma or asthma symptoms with the use of asthma medications, once the therapy is discontinued. Immunotherapy offers another strategy for asthma prevention, and groups treated with this intervention have demonstrated reduced atopy and asthma. Several multi-interventional trials have demonstrated a reduced asthma symptom burden but have not demonstrated significant differences in objective measures such as lung function or bronchial hyper-responsiveness between intervention groups. The most promising asthma prevention strategies to date have been those that use a multi-interventional approach employing both dietary and environmental manipulations. More research is needed to assess the long-term follow-up of multi-interventional trials and to evaluate novel intervention strategies in the primary or secondary prevention of asthma in childhood.

Omega-3 and omega-6 fatty acid exposure from early life does not affect atopy and asthma at age 5 years

The Childhood Asthma Prevention Study was a randomized controlled trial conducted in children with a family history of asthma in whom omega-3 fatty acid supplementation and restriction of dietary omega-6 fatty acids did not prevent asthma, eczema, or atopy at age 5 years. We sought to examine the relation of all measures of omega-3 and omega-6 polyunsaturated fatty acids with outcomes at age 5 years in the whole birth cohort, regardless of randomization group. Plasma fatty acids were measured at 18 months, 3 years, and 5 years. Compliance with the fatty acid supplements was estimated every 6 months. Dietary intake was assessed at 18 months by means of weighed-food record and at 3 years by means of food-frequency questionnaire. At age 5 years, 516 children were examined for wheeze and eczema (questionnaire) and atopy (skin prick tests, n = 488). Multiple logistic regression was used to evaluate associations between exposures and outcomes. Plasma levels of omega-3 or omega-6 fatty acids were not associated with wheeze, eczema, or atopy at age 5 years (P = .11-.96). Overall, fatty acid exposure, measured as plasma levels, dietary intake, and compliance with supplements, was not associated with any respiratory or allergic outcomes (P = .35-.59). This observational analysis of the cohort, using the full range of observed variation in omega-3 and omega-6 fatty acid exposure, supports the negative findings of the randomized controlled trial. Modification of dietary polyunsaturated fatty acids in early childhood is not helpful in preventing atopy and asthma.

S12-2-2 Prevention and treatment of early asthma in childhood(Part-2 "Educational Session of APAACI",Joint symposium with APAACI,English session)

S12-2-2 Prevention and treatment of early asthma in childhood(Part-2 "Educational Session of APAACI",Joint symposium with APAACI,English session)

Consumption of ‘extra’ foods (energy-dense, nutrient-poor) among children aged 16–24 months from western Sydney, Australia

AbstractObjectiveThis study evaluates the contribution of energy-dense, nutrient-poor ‘extra’ foods to the diets of 16–24-month-old children from western Sydney, Australia.DesignAn analysis of cross-sectional data collected on participants in the Childhood Asthma Prevention Study (CAPS), a randomised trial investigating the primary prevention of asthma from birth to 5 years. We collected 3-day weighed food records, calculated nutrient intakes, classified recorded foods into major food groups, and further classified foods as either ‘core’ or ‘extras’ according to theAustralian Guide to Healthy Eating.SettingPregnant women, whose unborn child was at risk of developing asthma because of a family history, were recruited from all six hospitals in western Sydney, Australia. Data for this study were collected in clinic visits and at participants’ homes at the 18-month assessment.ParticipantsFour hundred and twenty-nine children participating in the CAPS study; 80% of the total cohort.ResultsThe mean consumption of ‘extra’ foods was ∼150 g day− 1and contributed 25–30% of the total energy, fat, carbohydrate and sodium to the diets of the study children. ‘Extra’ foods also contributed around 20% of fibre, 10% of protein and zinc, and about 5% of calcium. Children in the highest quintile of ‘extra’ foods intake had a slightly higher but not significantly different intake of energy from those in the lowest quintile. However, significant differences were evident for the percentage of energy provided by carbohydrate and sugars (higher) and protein and saturated fat (lower). The intake of most micronutrients was also significantly lower among children in the highest quintile of consumption. The intake of ‘extra’ foods was inversely associated with the intake of core foods.ConclusionsThe high percentage of energy contributed by ‘extra’ foods and their negative association with nutrient density emphasise the need for dietary guidance for parents of children aged 1–2 years. These preliminary data on commonly consumed ‘extra’ foods and portion sizes may inform age-specific dietary assessment methods.

Consumption of ‘extra’ foods (energy-dense, nutrient-poor) among children aged 16–24 months from western Sydney, Australia

This study evaluates the contribution of energy-dense, nutrient-poor 'extra' foods to the diets of 16-24-month-old children from western Sydney, Australia. An analysis of cross-sectional data collected on participants in the Childhood Asthma Prevention Study (CAPS), a randomised trial investigating the primary prevention of asthma from birth to 5 years. We collected 3-day weighed food records, calculated nutrient intakes, classified recorded foods into major food groups, and further classified foods as either 'core' or 'extras' according to the Australian Guide to Healthy Eating. Pregnant women, whose unborn child was at risk of developing asthma because of a family history, were recruited from all six hospitals in western Sydney, Australia. Data for this study were collected in clinic visits and at participants' homes at the 18-month assessment. Four hundred and twenty-nine children participating in the CAPS study; 80% of the total cohort. The mean consumption of 'extra' foods was approximately 150 g day(-1) and contributed 25-30% of the total energy, fat, carbohydrate and sodium to the diets of the study children. 'Extra' foods also contributed around 20% of fibre, 10% of protein and zinc, and about 5% of calcium. Children in the highest quintile of 'extra' foods intake had a slightly higher but not significantly different intake of energy from those in the lowest quintile. However, significant differences were evident for the percentage of energy provided by carbohydrate and sugars (higher) and protein and saturated fat (lower). The intake of most micronutrients was also significantly lower among children in the highest quintile of consumption. The intake of 'extra' foods was inversely associated with the intake of core foods. The high percentage of energy contributed by 'extra' foods and their negative association with nutrient density emphasise the need for dietary guidance for parents of children aged 1-2 years. These preliminary data on commonly consumed 'extra' foods and portion sizes may inform age-specific dietary assessment methods.

The PREVASC Study: The Clinical Effect of a Multifaceted Educational Intervention to Prevent Childhood Asthma

Purpose of the Study. To evaluate the clinical effectiveness of a multifaceted education intervention to prevent childhood asthma. Study Population. General practitioners recruited 476 high-risk children during the prenatal period. Methods. These high-risk children were randomly assigned to either a control group, receiving usual care, or an intervention group, in which families received instruction from nurses on how to reduce exposure of newborns to dust mite, pet, and food allergens and passive smoking. Results. A total of 443 infants were followed up for 2 years. At 2 years of age, those in the intervention group (n = 222) had less asthma-like symptoms, including wheezing, shortness of breath, and nighttime cough, compared with those in the control group (n = 221). No significant differences in total and specific immunoglobulin E were found between the groups. During the first 2 years of life, the incidence of asthma-like symptoms was similar in both groups; however, subanalysis revealed a significant reduction in the females but not in the males in the intervention group. Conclusions. The intervention used in this study was not effective in reducing asthma-like symptoms in high-risk children during the first 2 years of life, although it was modestly effective at 2 years. Follow-up is necessary to confirm whether the intervention can actually prevent the development of asthma. Reviewer Comments. This is a well-designed study in a primary care environment to investigate the clinical effectiveness of a multifaceted approach to prevent the development of asthma in high-risk children. It seemed that the intervention was moderately able to reduce exposure to dust mite, pet, and food allergens, but no significant effect was observed on parentally observed symptoms or allergen-specific immunoglobulin E in the first 2 years of life. Perhaps a more focused intervention or longer follow-up period would have proven more useful. The effectiveness of a variety of multifaceted randomized intervention trials on asthma prevention has yet to be determined. Although a host of epidemiologic studies have helped identify risk factors, we will all be interested in determining whether any practical interventions may be promising in preventing asthma development.

Five‐year follow‐up on the PAT study: specific immunotherapy and long‐term prevention of asthma in children

A 3-year course of specific immunotherapy (SIT) in children with hay fever to grass and/or birch pollen significantly reduced the risk of developing asthma. To investigate the long-term preventive effect, we performed a follow up--2 years after termination of immunotherapy. A total of 183 children, aged 6-14 years with grass and/or birch pollen allergy could be investigated 2 years after discontinuation of SIT or no treatment. Conjunctival provocation tests (CPTs) and methacholine bronchial provocation tests were carried out during the season and winter after 5 years. The development of asthma was assessed by clinical evaluation. The significant improvement in hay fever and CPT results observed after 3 years of SIT persisted at the 5-year follow-up. No difference in bronchial responsiveness to methacholine was found after 5 years because of spontaneous improvement during the follow-up period in the control patients. The immunotherapy-treated children had significantly less asthma after 5 years as evaluated by clinical symptoms [odds ratio 2.68 (1.3-5.7)] in favor of SIT for prevention of development of asthma and significantly less patients reported an increase in asthma scores (P < 0.01). Immunotherapy for 3 years with standardized allergen extracts of grass and/or birch shows long-term clinical effect and preventive effect on development of asthma in children with seasonal rhinoconjunctivitis.

Primary prevention of childhood asthma and allergic disorders

The prevalence of asthma and allergic disorders in childhood is increasing in many parts of the world. This review focuses on recent findings with regard to environmental risk factors and their manipulation in the primary prevention of these diseases in childhood. Recent studies have failed to resolve the controversy on the subject of exposure to indoor aeroallergens and the risk of sensitization and asthma in childhood. Bronchiolitis due to respiratory syncytial virus in infancy is associated with a significant increase in risk of asthma, but not atopy. In the prevention of these diseases, the effects of breastfeeding are controversial, with studies showing a protective effect in children without allergic predisposition, but other studies showing no effect or even the potential for an increased asthma risk. A significant reduction in the prevalence of doctor-diagnosed asthma at 7 years was found in a randomized controlled multifaceted (reduction of inhaled and ingested allergens) intervention study of high-risk infants. Other intervention measures, such as an education program on how to reduce exposure, the use of probiotics, and immunization against infections, all showed some protective effects. More research is required, especially with regard to longer periods of follow-up for all current intervention studies aimed at reducing exposure, the onset and duration of intervention, and other novel intervention measures in the primary prevention of asthma and allergic diseases in childhood.

A 3-year Course of Subcutaneous Specific Immunotherapy Results in Long-term Prevention of Asthma in Children. Ten Year Follow-up on the PAT-Study

A 3-year Course of Subcutaneous Specific Immunotherapy Results in Long-term Prevention of Asthma in Children. Ten Year Follow-up on the PAT-Study

Respiratory Syncytial Virus Infection Reversed Anti-Asthma Effect of Neonatal Bacillus Calmette-Guerin Vaccination in BALB/c Mice

Bacillus Calmette-Guerin (BCG) vaccination can protect animals from asthma, but the effect of BCG on childhood asthma prevention is controversial in humans. To verify the hypothesis that the BCG anti-asthma effect in childhood might be reversed by a respiratory virus infection, newborn BALB/c mice were divided into five groups. Control and ovalbumin (OVA) groups were mock vaccinated and mock infected. The BCG/OVA group was BCG vaccinated and mock infected. The respiratory syncytial virus (RSV)/OVA group was mock vaccinated and RSV infected. The BCG/RSV/OVA group was BCG vaccinated and RSV infected. Except for the control group, all groups underwent OVA sensitization and challenge. Airway hyperresponsiveness (AHR) was measured after challenge and cells in bronchoalveolar lavage fluid (BALF) were counted. Cytokines in BALF and serum OVA-specific IgE were detected by ELISA and inflammatory characteristics of lung sections were scored. Mice with neonatal BCG vaccination (BCG/OVA group) were significantly protected from BALF eosinophilia, AHR to methacholine, peribronchiolitis, alveolitis, and peribronchial eosinophilia in comparison with the OVA, RSV/OVA, and BCG/RSV/OVA groups. AHR in the OVA group was greater than in the BCG/OVA group but lower than in the RSV/OVA and BCG/RSV/OVA groups. No significant differences in BALF eosinophilia, AHR, and lung inflammation were found between the RSV/OVA and BCG/RSV/OVA groups. The impact of BCG vaccination on anti-asthma in mice was not dependent on interferon-gamma, IL-4, and IL-10 levels. The results suggested that RSV infection can reverse the anti-asthma effect of neonatal BCG vaccination in BALB/c mice.

Update on Allergy Immunotherapy

This article summarizes and provides commentary regarding guidelines on the administration of immunotherapy (IT) for allergic airway disease. Recent investigations have provided important insights into the immunologic mechanism of IT and the prominent role of interleukin-10-producing regulatory T lymphocytes. The most important aspect of successful IT is the administration of an appropriate dose of an extract containing a sufficient concentration of the relevant allergen. This is largely possible now only with standardized extracts. When the major allergen content of successful IT extracts was quantified, efficacy was demonstrated across a surprisingly narrow concentration range (approximately 5-24 μg per injection), irrespective of the extract. This presumably reflects the concentration of an antigen that drives an immune response toward tolerance. It may be predicted that as major allergen content is quantified in currently nonstandardized extracts, effective IT will also be achieved by administering a dose in this range, in contrast to current practices involving fairly arbitrary dosing decisions. With the availability of nonsedating antihistamines, intranasal corticosteroids, and the leukotriene modifiers, inadequate pharmacologic response or intolerable side effects are less commonly the major indications for starting IT for allergic rhinitis (AR). However, with the recognition that a relatively short course (3-5 years) of IT can provide long-term immunomodulation and clinical benefit, a desire to avoid long-term pharmacotherapy and the associated high costs may be the primary indication for IT in AR cases. While evidence overwhelmingly supports the beneficial influences of IT in asthma cases, the positioning of IT for this disorder is not established. The observed prevention of asthma in children who have AR is intriguing, but further studies are required to assess the extent to which the prevalence and severity of chronic asthma will be reduced when these children reach adulthood. Similarly, safety issues overwhelmingly suggest that uncontrolled asthma is the greatest risk factor for mortality associated with IT and that IT therefore may be contraindicated for most patients who have inadequate pharmacologic responses or are unable to tolerate useful pharmacologic agents. Paradoxically, these are the patients for whom a response to IT may be most desirable.

Meat consumption among 18-month-old children participating in the Childhood Asthma Prevention Study

Objective: To document meat consumption among 18-month-old children, for use in refining population dietary assessment methods and dietary guidance for young children. Design: A secondary analysis of data collected in 1998–2000 from the 18 months follow up of the Childhood Asthma Prevention Study: an intervention trial of omega-3 oil supplementation and house-dust mite reduction, from birth to five years. Subjects and setting: Pregnant women whose unborn children had an atopic family history were recruited from antenatal clinics of six hospitals in western Sydney. Carers of 429 18-month-old children (80% response) satisfactorily completed three-day weighed food records. Main outcome measures: Mean and median intakes per day and portion sizes of various meats and meat products. Statistical analyses: T-tests for comparing gender differences; Pearson correlation and one-way analysis of variance for relationships between meat and nutrient intake. Results: During the recording period 94% of the children ate meat. McDonald's Chicken McNuggets™, beef mince, and beef sausages were the most frequently consumed meats. Median portion sizes ranged from 20–50 g, and were considerably smaller than ‘usual’ portions specified on food frequency questionnaires in common use. Higher meat diets in this age group were not associated with higher intakes of iron or zinc per MJ. Conclusion: The marginally low intakes of iron and zinc in this age group could be improved by greater use of cuts of red meat appropriately prepared for toddlers.

Three-Year Outcomes of Dietary Fatty Acid Modification and House Dust Mite Reduction in the Childhood Asthma Prevention Study

Peat JK, Mihrshahi S, Kemp AS, et al. J Allergy Clin Immunol . 2004;114:807–813 To measure the effects of dietary supplementation with ω-3 fatty acids and house d-e (HDM) allergen avoidance in children with a family history of asthma. Children at high risk for asthma, defined by having at least 1 parent or sibling with current asthma or frequent wheeze. A total of 616 children at high risk for asthma were enrolled antenatally, …

The primary prevention of asthma in children study: Design of a multifaceted prevention program

The PREVASC study addresses the primary prevention of asthma in infants and small children. The objective of this study is to investigate whether a multifaceted prenatally started intervention strategy in high-risk infants leads to a decrease in the occurrence of (severe) asthma and whether a refinement of the prevention strategy leads to an increase in the adherence to the prevention program. The primary prevention program includes house dust mite impermeable bed coverings, education on breast feeding, hypoallergenic feeding, timing of introduction of solid food and smoking cessation. A total of 888 infants were prenatally included. By the time of inclusion the mothers were 3-7 months pregnant. About 27 infants were excluded from the study and 18 dropped out. Of the remaining 843 infants 535 had a first-degree familial predisposition of asthma (high-risk group), whereas a reference group of 308 (162 boys) infants was not predisposed for asthma in the first-degree (low-risk group). To evaluate the (cost-)effectiveness of the preventive intervention, 222 (118 boys) infants of the high-risk group allocated to the intervention group and 221 (112 boys) allocated to a control group are followed up. The low-risk infants served as controls to evaluate the predictive value of high risk (first-degree familial predisposition of asthma). The infants are followed from the prenatal stage until they reach the age of 6 yr. The remaining 92 high-risk infants were included in an optimized randomized-clinical adherence trial (RCAT). Of these 92 infants, 45 (20 boys) were allocated to an intervention group and 47 (24 boys) to a control group. Until now all infants have been followed for at least 1 yr.

Beyond the Bench: Mapping the Air in Public Schools

In the home, parents are the primary guardians of a child’s environmental health. However, once the child’s environment moves out of the home, identifying sources of protection can become difficult. The Community Outreach and Education Program (COEP) of Duke University’s NIEHS Environmental Health Sciences Research Center in Durham, North Carolina, has pledged to give children’s environmental health the attention it deserves and is proactively implementing projects to create preventive environmental interventions that protect children before they become sick. One of the main questions the Duke COEP seeks to answer in its outreach activities is whether children are being exposed to environmental factors in school that contribute to asthma incidence. The Duke COEP staff have used geographic information system (GIS) technology in a number of applications to address this question, including a May 2004 assessment of the indoor air environment at nearby New Hope Elementary School. For years, students and staff in the Orange County school system (of which New Hope Elementary is a part) had complained of respiratory problems as well as general discomfort with fluctuating indoor temperatures and a sense that the air in the school buildings was unhealthy. COEP staff were asked to evaluate one sample school in the system and offer recommendations. They selected New Hope Elementary for study, then went into the school and conducted an evaluation of every classroom. The problems they observed included a high relative indoor humidity of around 75–78% (the ideal humidity is 35–40% when the outdoor temperature is 20°F or higher) and imbalances in the heating and cooling system (they observed temperature differences of as much as 5–10°F in separate classrooms in some instances). They also noticed problems exacerbated by failing insulation, such as mold spore development and air flow variations—some rooms would have a distinct breeze, while others had still, damp air. Once they had gathered their data, the COEP staff created a GIS compilation to display the data and analyze the results. The advantage of using GIS technology to interpret information is that it visually integrates previously unlinked sets of information, facilitating the detection of relationships among them. In the case of New Hope Elementary, the GIS map let concerned parents, teachers, school administrators, and education policy makers see a visual representation of the spatial distribution of airflow irregularities and mold spores throughout the school. Based on information gathered from the GIS map, the school administrators replaced carpeting throughout the school with tile floors and thoroughly cleaned the entire duct system, which significantly improved ventilation in the classrooms. “What’s exciting is that we were able to provide information, education, and outreach directly to the faculty and school governance council,” says Marie Lynn Miranda, director of the Duke COEP. Another benefit of the study is the unique learning opportunity it will afford the New Hope Elementary students. All the data from the project will be turned over to the school’s fifth-grade science teachers for development into classroom lesson projects. COEP workers also plan to use the New Hope Elementary study as a model for future initiatives in childhood asthma prevention.

Asthma Management Issues in Infancy and Childhood

The prevalence of asthma has been increasing worldwide over the past 2 decades, especially the prevalence of childhood asthma. Currently, the prevalence of childhood asthma is around 3-20% in different countries based on the report from the International Study of Asthma and Allergies in Children (ISAAC). Asthma in childhood is predominantly an extrinsic asthma. In general, countries in the coastal, temperate, and subtropical zones have the highest prevalence of mite- and cockroach-sensitive asthma. Countries in the sub-arctic or semi-arid areas have a lower prevalence of childhood asthma, mostly associated with sensitization to pet dander, moulds, and pollens. Many genes have been linked to asthma in different ethnic populations. A global consensus for the management of asthma in adults and children >5 years of age has been made possible in the Global Initiative for Asthma (GINA) guidelines, where a step-wise management program using inhaled medication with and without oral anti-inflammatory drugs is recommended. The management of asthma in children <5 years of age remains inconclusive. Recent studies suggest that inherited susceptibility associated with risk factors from the prenatal and postnatal environment is likely to promote allergic sensitization and development of asthma. Consequently, early prevention of prenatal sensitization in utero and environmental control of early life exposure to various allergens may decrease the incidence of childhood asthma. In the management of moderate persistent asthma in infants and young children <5 years of age, airway resistance tests (FEV(1) or PEF) are not of significance, but assessment of respiratory rate and skin pulse oximeter measurements of arterial oxygen saturation are helpful. Moreover, recent advances in pharmacogenetics and pharmacogenomics may provide better individualized care for early pharmacological prevention of childhood asthma via selective modulation of airway remodeling.

Short-term Impact of a Randomized Multifaceted Intervention for Wheezing Infants in Low-Income Families

To present an interim analysis of the effect of a home-based intervention with low-income caregivers of wheezing infants at risk for childhood asthma on mediating variables. Infants aged 9 to 24 months with 3 or more physician-documented wheezing episodes were randomly assigned to environmental support intervention (ES) (n = 90) or control (n = 91) groups. Nurse home visitors intervened for 1 year to decrease allergen and environmental tobacco smoke exposure and improve symptom perception and management. Assessments at baseline and 12 months included allergens in house dust, infant urinary cotinine levels, caregivers' symptom reports, quality of life, illness management, and quality of caregiving. Medical records were coded for hospitalizations, emergency department visits, and corticosteroid bursts. Within the ES group, cockroach allergen levels were significantly reduced and there was a trend toward reduction in dog dander levels. Among infants with detectable urinary cotinine, levels were significantly reduced in the ES group. Caregiver psychological resources modified the impact, and low-resource ES caregivers were the most strongly affected. Asthma knowledge and provider collaboration improved significantly in the ES group. Neither reports of infant symptoms nor emergency department visits or hospitalizations showed positive intervention effects. Number of corticosteroid bursts for infants was significantly higher for the ES group. The Childhood Asthma Prevention Study intervention was effective in reducing several environmental exposures and improving illness management. However, even with an intensive home-based intervention, we failed to reduce respiratory symptoms or medical use in the ES group relative to the control group, illustrating the difficulty of changing the course of early asthma development among low-income infants.