Interactive effect of family history and environmental factors on respiratory tract-related morbidity in infancy

Smoking in the family is most predictive of the development of childhood asthma in preterm babies <30 weeks gestation: Results of the Respiratory Outcomes Study 2 (RESPOS2)

OBJECTIVES

The Respiratory Outcomes Study 2 (RESPOS2) investigated the relationship between neonatal outcomes (specifically, chronic lung disease [CLD]) and environmental factors on the development of asthma and atopic outcomes at primary school age for preterm babies (PBs) <30 weeks gestational age (GA).

METHODS

The study included all surviving PBs <30 weeks GA admitted to the Neonatal Intensive Care Unit at Canberra Hospital, Australian Capital Territory between 2007 and 2009. Parents were sent a questionnaire regarding asthma and atopy symptoms when the PBs were aged 5-7 years old. Data were compared based on CLD status.

RESULTS

There were 103 PBs included in the study with a 68.9% response rate to the respiratory questionnaire (71/103). Of these PBs, 15/71 (21.1%) received a diagnosis of CLD. There were no significant differences with regards to asthma, hay fever or eczema in PBs either with or without CLD. The most significant predictor for the development of asthma was smoking in the family (Odds Ratio [OR]: 11.66, 95% Confidence Interval [CI]: 2.01-67.56) with a trend toward significance for family history of asthma (OR: 3.83, 95% CI: 0.85-17.25).

CONCLUSION

The RESPOS2 has confirmed previous reports that CLD in PBs <30 weeks GA is not associated with the development of childhood asthma, hay fever or eczema. In our group of PBs, the strongest predictor of the development of asthma was smoking in the family.

Acute Otitis Media During Infancy: Parent-reported Incidence and Modifiable Risk Factors

BACKGROUND

Age at exposure to acute otitis media (AOM) risk factors such as day care attendance, lack of breastfeeding and tobacco smoke is little studied but important for targeting AOM prevention strategies. Moreover, studies are typically restricted to clinically diagnosed AOM, while a significant subset can occur outside the health care system, depending on the country setting. This study aims to determine risk factor exposure and effect of its timing within the first year of life on parent-reported AOM symptom episodes.

METHODS

In the WHeezing and Illnesses STudy LEidsche Rijn birth-cohort study, 1056 children were prospectively followed during their first year of life. Group day care attendance, breastfeeding and tobacco smoke exposure were recorded monthly and parent-reported AOM symptoms daily. Generalized estimating equations were used to estimate the association between the time-varying risk factors and AOM symptom episodes, while correcting for confounding by indication.

RESULTS

The first-year incidence rate of parent-reported AOM was 569/1000 child-years [95% confidence interval (CI): 523-618]. Children who attended day care had higher odds of developing AOM symptom episodes compared with those not attending (odds ratio: 5.0; 95% CI: 2.6-9.6). Tobacco smoke exposure and (a history of) breastfeeding were not associated with AOM. Test for interaction revealed that the effect of day care increased with each month younger in age.

CONCLUSIONS

First-year day care attendance is a major risk factor for AOM symptom episodes among infants in the community. This adjusted effect estimate is higher than previously reported and is age-dependent. AOM prevention strategies in day care facilities should therefore focus in particular on the youngest age groups.

Cost-effectiveness of primary prevention of paediatric asthma: a decision-analytic model

BACKGROUND

Many children stand to benefit from being asthma-free for life with primary (i.e., prenatally started) prevention addressing one environmental exposure in a unifaceted (UF) approach or at least two in a multifaceted (MF) approach. We assessed the cost-effectiveness of primary prevention programmes for Dutch children in a decision-analytic framework.

METHODS

A decision-analytic tree model analysing healthcare costs and asthma cases prevented was developed to compare usual care (UC) with two UF and three MF programmes on the primary prevention of asthma amongst children. Programmes were evaluated through incremental cost-effectiveness ratios and net monetary benefits. Decision and parameter uncertainty were subjected to value-of-information analyses.

RESULTS

The current UC and one of three MF programmes dominated the other alternatives. The MF programme was more costly but also more effective than UC at an incremental cost-effectiveness ratio of <euro>8,209.20/additional asthma case prevented. The value of perfect information to reduce uncertainty was <euro>291.6M at its lowest. Most of the uncertainty in the cost-effectiveness threshold was attributable to the probability and cost estimates for low-risk children.

CONCLUSION

This study supports the feasibility of a structured programme that simultaneously addresses exposure to house dust mites, pet dander, environmental tobacco, and breast-feeding as a cost-effective alternative to UC in the primary prevention of asthma amongst children.

Addressing passive smoking in children

BACKGROUND

A significant number of parents are unaware or unconvinced of the health consequences of passive smoking (PS) in children. Physicians could increase parental awareness by giving personal advice.

AIM

To evaluate the current practices of three Dutch health professions (paediatricians, youth health care physicians, and family physicians) regarding parental counselling for passive smoking (PS) in children.

METHODS

All physicians (n = 720) representing the three health professions in Limburg, The Netherlands, received an invitation to complete a self-administered electronic questionnaire including questions on their: sex, work experience, personal smoking habits, counselling practices and education regarding PS in children.

RESULTS

The response rate was 34%. One tenth (11%) of the responding physicians always addressed PS in children, 32% often, 54% occasionally and 4% reported to never attend to it. The three health professions appeared comparable regarding their frequency of parental counselling for PS in children. Addressing PS was more likely when children had respiratory problems. Lack of time was the most frequently mentioned barrier, being very and somewhat applicable for respectively 14% and 43% of the physicians. One fourth of the responders had received postgraduate education about PS. Additionally, 49% of the responders who did not have any education about PS were interested in receiving it.

CONCLUSIONS

Physicians working in the paediatric field in Limburg, The Netherlands, could more frequently address PS in children with parents. Lack of time appeared to be the most mentioned barrier and physicians were more likely to counsel parents for PS in children with respiratory complaints/diseases. Finally, a need for more education on parental counselling for PS was expressed.

Prenatal origins of bronchiolitis: protective effect of optimised asthma management during pregnancy

Objective

Maternal asthma is the most common chronic disease complicating pregnancy and is a risk factor for bronchiolitis in infancy. Recurrent episodes of bronchiolitis are strongly associated with the development of childhood asthma.

Methods

We conducted a follow-up study of infants born to women with asthma who completed a double-blind randomised controlled trial during pregnancy. In this trial, pregnant women with asthma were assigned to treatment adjustment by an algorithm using clinical symptoms (clinical group) or the fraction of exhaled nitric oxide (FeNO group) and we showed that the FeNO group had significantly lower asthma exacerbation rates in pregnancy.

Results

146 infants attended the 12-month follow-up visit. Infants born to mothers from the FeNO group were significantly less likely to have recurrent episodes of bronchiolitis in the first year of life (OR 0.08, 95% CI 0.01 to 0.62; p=0.016) as compared with the clinical group.

Conclusions

Optimised management of asthma during pregnancy may reduce recurrent episodes of bronchiolitis in infancy, which could potentially modulate the risk to develop or the severity of emerging childhood asthma.

Global strategies for reducing the burden from asthma

Asthma is one of the most important chronic diseases in childhood. For several decades, a steady increase in prevalence has been observed worldwide. In the structural collaboration between the Centre for Population Health Services in Edinburgh and the Research Institute CAPHRI of Maastricht we investigated the possibilities for primary prevention of asthma in childhood. We found that a multifaceted approach might be effective in delaying or preventing asthma, whereas a mono-intervention does not seem to have such a protective effect. 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. Underdiagnosis of asthma is still a big problem in primary care. Most patients do not present bronchial symptoms to the general practitioner, even though they have decreased lung function, so they remain unknown and undiagnosed. However, patients who do present with respiratory problems and who have reduced lung function are not always recognised as such. We found that the perception of dyspnoea seems to determine, at least in part, the presentation to the general practitioner with symptoms. These observations show that both the prevention of the development of asthma in early childhood, as well as case finding of asthma in adulthood, do not seem to be very effective in primary care. More research is needed to clarify what steps can be taken to reduce the global burden from asthma.

A motivational interviewing intervention to PREvent PAssive Smoke Exposure (PREPASE) in children with a high risk of asthma: design of a randomised controlled trial

Background

Especially children at risk for asthma are sensitive to the detrimental health effects of passive smoke (PS) exposure, like respiratory complaints and allergic sensitisation. Therefore, effective prevention of PS exposure in this group of vulnerable children is important. Based on previous studies, we hypothesized that an effective intervention program to prevent PS exposure in children is possible by means of a motivational interviewing tailored program with repeated contacts focussing on awareness, knowledge, beliefs (pros/cons), perceived barriers and needs of parents, in combination with feedback about urine cotinine levels of the children. The aim of the PREPASE study is to test the effectiveness of such an intervention program towards eliminating or reducing of PS exposure in children at risk for asthma. This article describes the protocol of the PREPASE study.

Methods

The study is a one-year follow-up randomized controlled trial. Families with children (0–13 years of age) having an asthma predisposition who experience PS exposure at home are randomized into an intervention group receiving an intervention or a control group receiving care as usual. The intervention is given by trained research assistants. The intervention starts one month after a baseline measurement and takes place once per month for an hour during six home based counselling sessions. The primary outcome measure is the percentage of families curtailing PS exposure in children (parental report verified with the urine cotinine concentrations of the children) after 6 months. The secondary outcome measures include: household nicotine level, the child’s lung function, airway inflammation and oxidative stress, presence of wheezing and questionnaires on respiratory symptoms, and quality of life. A process evaluation is included. Most of the measurements take place every 3 months (baseline and after 3, 6, 9 and 12 months of study).

Conclusion

The PREPASE study incorporates successful elements of previous interventions and may therefore be very promising. If proven effective, the intervention will benefit the health of children at risk for asthma and may also create opportunity to be tested in other population.

Trial registration number

NTR2632

Social cognitive changes resulting from an effective breastfeeding education program

Infants of parents with a history of asthma could benefit from exclusive breastfeeding during the first 6 months of life to reduce the chance of developing childhood asthma. Continuing to breastfeed for 6 months seemed difficult to perform for many Dutch women. Therefore, an educational breastfeeding program was developed and implemented. The program (a theory-based booklet and pre- and postnatal home visits by trained assistants) significantly improved exclusive breastfeeding rates at 6 months postpartum (48% for intervention vs. 27% for control). Repeated-measurements analyses showed significant increases in knowledge and more positive attitudinal beliefs regarding breastfeeding for 6 months, in particular immediately after exposure to the program, compared with the controls. As expected, over time perceived self-efficacy and women's positive emotions toward breastfeeding increased, and support for breastfeeding diminished in both groups. The intervention group was reported to perceive more pressure to bottle feed and to know more breastfeeding models than the control group. Implications for practice are discussed.

The effect of parental allergy on childhood allergic diseases depends on the sex of the child

BACKGROUND

The parent-of-origin effect is important in understanding the genetic basis of childhood allergic diseases and improving our ability to identify high-risk children.

OBJECTIVE

We sought to investigate the parent-of-origin effect in childhood allergic diseases.

METHODS

The Isle of Wight Birth Cohort (n= 1456) has been examined at 1, 2, 4, 10, and 18 years of age. Information on the prevalence of asthma, eczema, rhinitis, and environmental factors was obtained by using validated questionnaires. Skin prick tests were carried out at ages 4, 10, and 18 years, and total IgE measurement was carried out at 10 and 18 years. Parental history of allergic disease was assessed soon after the birth of the child, when maternal IgE levels were also measured. Prevalence ratios (PRs) and their 95% CIs were estimated, applying log-linear models adjusted for confounding variables.

RESULTS

When stratified for sex of the child, maternal asthma was associated with asthma in girls (PR, 1.91; 95% CI, 1.34-2.72; P= .0003) but not in boys (PR, 1.29; 95% CI, 0.85-1.96; P= .23), whereas paternal asthma was associated with asthma in boys (PR, 1.99; 95% CI, 1.42-2.79; P< .0001) but not in girls (PR, 1.03; 95% CI, 0.59-1.80; P= .92). Maternal eczema increased the risk of eczema in girls (PR, 1.92; 95% CI, 1.37-2.68; P= .0001) only, whereas paternal eczema did the same for boys (PR, 2.07; 95% CI, 1.32-3.25; P = .002). Similar trends were observed when the effect of maternal and paternal allergic disease was assessed for childhood atopy and when maternal total IgE levels were related to total IgE levels in children at ages 10 and 18 years.

CONCLUSIONS

The current study indicates a sex-dependent association of parental allergic conditions with childhood allergies, with maternal allergy increasing the risk in girls and paternal allergy increasing the risk in boys. This has implications for childhood allergy prediction and prevention.

Viral Disease, Air Pollutants, Nanoparticles, and Asthma

Health care providers who treat patients with respiratory disease are often asked by their patients, “What caused my asthma? And what causes my asthma suddenly to become worse?” These questions have always been difficult to answer, and moving directly to a discussion of the management of asthma is a much easier road to take. In recent years, though, enough information has accumulated about the causes of asthma that one can weave a story containing useful advice that may help patients participate in the management of their disease. And there are also recent studies that can provide answers to the questions posed by physicians who have watched in puzzlement as their previously well-controlled asthma patients have spiraled rapidly out of control. This story has been growing increasingly complex, with an ever-expanding cast of players that sometimes creates a tangled web of interactions.

Structuring and validating a cost-effectiveness model of primary asthma prevention amongst children

BACKGROUND

Given the rising number of asthma cases and the increasing costs of health care, prevention may be the best cure. Decisions regarding the implementation of prevention programmes in general and choosing between unifaceted and multifaceted strategies in particular are urgently needed. Existing trials on the primary prevention of asthma are, however, insufficient on their own to inform the decision of stakeholders regarding the cost-effectiveness of such prevention strategies. Decision analytic modelling synthesises available data for the cost-effectiveness evaluation of strategies in an explicit manner. Published reports on model development should provide the detail and transparency required to increase the acceptability of cost-effectiveness modelling. But, detail on the explicit steps and the involvement of experts in structuring a model is often unevenly reported. In this paper, we describe a procedure to structure and validate a model for the primary prevention of asthma in children.

METHODS

An expert panel was convened for round-table discussions to frame the cost-effectiveness research question and to select and structure a model. The model's structural validity, which indicates how well a model reflects the reality, was determined through descriptive and parallel validation. Descriptive validation was performed with the experts. Parallel validation qualitatively compared similarity between other published models with different decision problems.

RESULTS

The multidisciplinary input of experts helped to develop a decision-tree structure which compares the current situation with screening and prevention. The prevention was further divided between multifaceted and unifaceted approaches to analyse the differences. The clinical outcome was diagnosis of asthma. No similar model was found in the literature discussing the same decision problem. Structural validity in terms of descriptive validity was achieved with the experts and was supported by parallel validation.

CONCLUSIONS

A decision-tree model developed with experts in round-table discussions benefits from a systematic and transparent approach and the multidisciplinary contributions of the experts. Parallel validation provides a feasible alternative to validating novel models. The process of structuring and validating a model presented in this paper could be a useful guide to increase transparency, credibility, and acceptability of (future, novel) models when experts are involved.

Prevalence of and risk factors for wheezing in the first year of life

OBJECTIVE

To determine the prevalence of and the risk factors for wheezing in infants under one year of age and residing in the city of Porto Alegre, Brazil.

METHODS

This was a cross-sectional study and is part of a multicenter, multinational project. The parents or legal guardians of the infants were interviewed at primary health care clinics or during home visits. We used a standardized questionnaire, validated for use in Brazil. Potential risk factors were assessed by means of a Poisson regression model with robust variance estimation, using the Wald test to determine the significance of each variable in the model.

RESULTS

The sample comprised 1,013 infants. The majority of those were male (53%), and the mean age was 13.5 ± 1.2 months. In 61% of the infants, there had been at least one episode of wheezing, which had recurred at least three times in one third of those infants. The mean age at the first episode of wheezing was 5.16 months (median, 5 months). Over 40% of the infants with wheezing visited emergency rooms due to wheezing, and 17% of those were hospitalized at least once in the first year of life because of this symptom. In the multivariate analysis, the risk factors for wheezing were as follows: male gender; history of pneumonia; maternal smoking during pregnancy; day care center attendance; low maternal level of education; early weaning; multiple episodes of cold; first viral infection prior to 3 months of age; existence of siblings; and history of asthma in the nuclear family.

CONCLUSIONS

The prevalence of wheezing is high among infants in the city of Porto Alegre. We identified various risk factors for wheezing in infants.

Factors associated with acute respiratory illness in day care children

The aim of this study was to investigate the relationship between child characteristics, parental and environmental factors and the occurrence of acute respiratory illness (ARI) and acute otitis media (AOM) among Finnish children attending day care centres (DCCs). The study was a cross-sectional questionnaire of 594 children aged 1-6 y from 18 DCCs in Helsinki, Finland. Recurrent (> or =4 diseases/y) ARI was present in 44% of the 1-3-y-olds and 23% of the 4-6-y-olds, and recurrent AOM in 15% and 2.5%, respectively. Parent atopic disease (odds ratio (OR) 1.53, p = 0.033), mother's academic education (OR 1.77, p = 0.008) and a medium length of DCC attendance compared to a short period (OR 1.67, p = 0.049) increased, while furry pets (OR 0.44, p = 0.003) and older child age (OR 0.38, p < 0.001) reduced the risk of recurrent ARI. Recurrent ARI (OR 3.96, p = 0.008), mother's academic education (OR 5.02, p = 0.003), and a medium length of DCC attendance compared to a short period (OR 3.34, p = 0.044) increased, while partial breastfeeding > or =6 months (OR 0.20, p = 0.002) and older child age (OR 0.05, p < 0.001) reduced the risk of recurrent AOM. Parental and environmental factors had a significant impact on recurrent ARI and AOM episodes in children attending DCCs. These risk factors should be considered in future studies intending to reduce DCC infections.

What are the risks associated with formula feeding? A re-analysis and review

BACKGROUND

Most infant feeding studies present infant formula use as "standard" practice, supporting perceptions of formula feeding as normative and hindering translation of current research into counseling messages supportive of exclusive breastfeeding. To promote optimal counseling, and to challenge researchers to use exclusive breastfeeding as the standard, we have reviewed the scientific literature on exclusive breastfeeding and converted reported odds ratios to allow discussion of the "risks" of any formula use.

METHODS

Studies indexed in PubMed that investigated the association between exclusive breastfeeding and otitis media, asthma, types 1 and 2 diabetes, atopic dermatitis, and infant hospitalization secondary to lower respiratory tract diseases were reviewed. Findings were reconstructed with exclusive breastfeeding as the standard, and levels of significance calculated.

RESULTS

When exclusive breastfeeding is set as the normative standard, the re-calculated odds ratios communicate the risks of any formula use. For example, any formula use in the first 6 months is significantly associated with increased incidence of otitis media (OR: 1.78, 95% CI: 1.19, 2.70 and OR: 4.55, 95% CI: 1.64, 12.50 in the available studies; pooled OR for any formula in the first 3 mo: 2.00, 95% CI: 1.40, 2.78). Only shorter durations of exclusive breastfeeding are available to use as standards for calculating the effect of "any formula use" for type 1 diabetes, asthma, atopic dermatitis, and hospitalization secondary to lower respiratory tract infections.

CONCLUSIONS

Exclusive breastfeeding is an optimal practice, compared with which other infant feeding practices carry risks. Further studies on the influence of presenting exclusive breastfeeding as the standard in research studies and counseling messages are recommended.

Epidemiology, natural history, and risk factors: panel report from the Ninth International Research Conference on Otitis Media

The 2007 Recent Advances in Otitis Media Research Conference Panel Report provides an update on otitis media (OM) research published from 2003 to 2007. This report summarizes important trends in disease incidence and prevalence, describes established and newly identified risk factors for acute and chronic OM and OM with effusion, and conveys information on newly discovered genetic factors. In this report, researchers have described declining rates of OM diagnosis, antibiotic prescriptions, offices visits for OM, and middle ear surgery since the licensure and routine use of pneumococcal conjugate vaccine in infants. The panel report also recommends short and long term goals for current and future OM research.

Determinants in early life for asthma development

A reliable screening test in newborns for the subsequent development of bronchial asthma (BA) has not been found yet. This is mainly due to the complexity of BA, being made up by different types and underlying mechanisms. In different studies, a number of risk factors for BA have been identified. These include a positive family history of BA, passive smoking (also during pregnancy), prematurity (including pulmonary infections, RDS and BPD), early viral respiratory infections (such as RSV-bronchiolitis), male gender, early lung function abnormalities and atopic constitution. The major risk factor for persistent BA is an underlying allergic constitution. Therefore, early symptoms and markers of allergy (i.e. The Allergic March) and a positive family history for allergy should be considered as important risk factors for the development of BA.

Characterization of regulatory T cells in urban newborns

BACKGROUND

In the United States, asthma prevalence is particularly high among urban children. Although the underlying immune mechanism contributing to asthma has not been identified, having impaired T regulatory (Treg) cells at birth may be a determining factor in urban children. The objective of this study was to compare Treg phenotype and function in cord blood (CB) of newborns to those in peripheral blood (PB) of a subset of participating mothers.

METHODS

Treg numbers, expression, and suppressive function were quantified in subjects recruited prenatally from neighborhoods where >/= 20% of families have incomes below the poverty line. Proportion of Treg cells and expression of naïve (CD45RA) or activated (CD45RO, CD69, and HLA-DR) markers in CD4+T cells was measured by flow cytometry. Treg suppressive capacity was determined by quantifying PHA-stimulated lymphocyte proliferation in mononuclear cell samples with and without CD25 depletion.

RESULTS

In an urban cohort of 119 newborns and 82 mothers, we found that newborns had similar number of cells expressing FOXP3 as compared to the mothers but had reduced numbers of CD4+CD25+bright cells that predominantly expressed the naïve (CD45RA) rather than the activated/memory (CD45RO) phenotype found in the mothers. Additionally, the newborns had reduced mononuclear cell TGF-beta production, and reduced Treg suppression of PHA-stimulated lymphocyte proliferation compared to the mothers.

CONCLUSION

U.S. urban newborns have Treg cells that express FOXP3, albeit with an immature phenotype and function as compared to the mothers. Longitudinal follow-up is needed to delineate Treg cell maturation and subsequent risk for atopic diseases in this urban birth cohort.

Breastfeeding and allergies: time for a change in paradigm?

PURPOSE OF REVIEW

This review examines recent studies of the relationships between breastfeeding and the epidemiology of allergic diseases, especially atopic dermatitis in infants and asthma in early and later childhood.

RECENT FINDINGS

Results from observational birth cohort studies, case-control studies, and one cluster randomized intervention trial have generally failed to demonstrate a protective effect of breastfeeding on outcomes of atopic dermatitis, allergic sensitization, wheezing, or asthma. Difficulties in interpretation relate to the absence of nonbreastfed control or reference groups in some studies, meaning outcomes can only be compared between different durations of breastfeeding. Studies with a nonbreastfed control group suggest there is an increased risk for atopy and asthma associated with breastfeeding and that prolonged breastfeeding may eventually reduce this increased risk. The family history, sex of the child, and the presence of other risk factors for allergy and asthma also influence the outcome.

SUMMARY

Although breastfeeding is strongly recommended for its multiple benefits on child health, most recent studies do not confirm the 'conventional wisdom' that breastfeeding is protective against allergy and asthma. Early reduction in childhood wheezing may reflect protection from viral infections, but allergies and asthma at later ages may be increased.

Nonlinear relationship of mite allergen exposure to mite sensitization and asthma in a birth cohort

BACKGROUND

There is uncertainty about the nature of the relationship between mite allergen exposure during infancy and the expression of allergic diseases in childhood.

OBJECTIVE

We sought to explore the relationships between repeated measurements of mite allergen exposure during the first 5 years of life and clinical allergic disease outcomes at age 5 years.

METHODS

In a birth cohort of 516 at-risk children, 13 bed dust samples were collected between birth and 5 years of age and analyzed for mite allergen. At age 5 years, the presence of mite atopy was assessed based on skin prick test results, and clinical assessments for asthma, eczema, and wheeze were conducted. The association of allergen exposure with each clinical outcome was examined by means of logistic regression, with adjustments for potential confounders.

RESULTS

The lowest and highest mite exposure quintiles, expressed as mean allergen concentration averaged over 0 to 5 years, were associated with a lower prevalence of mite atopy and of asthma compared with intermediate levels of exposure. These relationships, when determined by using average allergen concentration over 0 to 18 months, were weaker.

CONCLUSIONS

This study demonstrates a nonlinear relationship between mite allergen exposure and clinical outcomes in this generally high mite allergen environment.

Natural history of asthma: persistence versus progression-does the beginning predict the end?

Environmental exposures during the early years and airway obstruction that develops during this time, in conjunction with genetic susceptibility, are important factors in the development of persistent asthma in childhood. Established risk factors for childhood asthma include frequent wheezing during the first 3 years, a parental history of asthma, a history of eczema, allergic rhinitis, wheezing apart from colds, and peripheral blood eosinophilia, as well as allergic sensitization to aeroallergens and certain foods. Risk factors for the development of asthma in adulthood remain ill defined. Moreover, reasons for variability in the clinical course of asthma--persistence in some individuals and progression in others--remain an enigma. The distinction between disease persistence and disease progression suggests that these are different entities or phenotypes. There is currently no consensus on whether disease progression requires either airway inflammation or airway remodeling or the combination of the two. For patients with irreversible airway obstruction, inflammation might, in part, be necessary but perhaps not entirely sufficient to induce the irreversible component, some of which could be attributed to alterations in the structure of the bronchial wall. Intervening with intermittent or daily inhaled corticosteroids in high-risk infants and children does not prevent disease progression or impaired lung growth. These findings, however, might not apply to adults, and further study in adults is needed to determine the effect of inhaled corticosteroid therapy on disease progression.

Early respiratory infections and asthma among New York City Head Start children

BACKGROUND

Respiratory infections in neonates have been found to predict wheeze among young children. We hypothesized that among preschool children from low-income minority communities in New York City, current asthma would be associated with a history of respiratory infection in the first few months after their birth.

METHODS

We asked parents of children in New York City Head Start centers (preschool programs for children of low-income families) to respond to a questionnaire covering demographic factors, lifestyle, home environment, and health history, including a detailed history of respiratory conditions. We used logistic regression to model the association of asthma and asthma severity with history of respiratory infections, controlling for gender, ethnicity, family history of asthma, and other factors.

RESULTS

Among 1,022 children (mean age 4+/- 0.6 years) whose parents provided information about their health history, 359 (35%) met our criteria for asthma. Overall, 22% had had a cold by 6 months and 17% an ear infection by 8 months of age. In multivariable models, children with asthma had had more colds (OR = 2.8, 95% confidence interval [CI] 1.4-6.0) and ear infections (OR = 3.4, 95% CI 1.7-6.9) in the past year than other children. Associations of respiratory infections with emergency department use for asthma (as a measure of severity) were similar. In models that did not control for infections in the past year, ages at first cold and first ear infection were associated with asthma and emergency department visits in the past year.

CONCLUSIONS

In this sample of preschool children, respiratory infections were common and were associated with asthma and health care utilization for asthma exacerbations. If these findings are confirmed, preventive measures among children who develop such infections at a very early age should be explored to help reduce the burden of asthma in this age group.

Advances in the care of adults with asthma and allergy in 2007

In 2007 the National Asthma Education and Prevention Program published the Expert Panel Report 3, updating its 1997 and 2002 guidelines for the diagnosis and management of asthma with new emphasis on assessment and attainment of control. This review focuses on the Journal articles published in 2007 pertaining to risk and impairment in adult asthma and interventions to improve its control.

Benefícios da amamentação para a saúde da mulher e da criança: um ensaio sobre as evidências

Este ensaio reúne uma seleção de estudos, particularmente revisões sistemáticas que têm contribuído para aumentar a compreensão sobre os benefícios do aleitamento materno para a criança e para a mulher e sua implementação. Realizou-se uma busca de artigos publicados a partir do ano 2000, sem, no entanto, deixar de lado estudos relevantes para o avanço do conhecimento publicados décadas atrás. Para a seleção dos estudos efetuou-se uma busca na Internet com base nas ferramentas disponíveis no PubMed e SciELO. Além dos aspectos para os quais há consenso, procurou-se incluir estudos sobre resultados controversos e outros que são instigantes, como os provenientes da neurobiologia. Verificam-se mudanças substanciais nas recomendações para políticas públicas em decorrência desses novos conhecimentos. Algumas investigações também têm sido realizadas com o objetivo de avaliar quais intervenções seriam mais efetivas para um aumento das práticas de amamentação. Procurou-se neste artigo dar destaque a: recomendações atuais sobre alimentação da criança pequena; importância da amamentação no início da vida; implicações do aleitamento materno para a saúde da criança; implicações do aleitamento materno para a saúde da mulher; e efetividade de algumas ações pró-amamentação.