Relationships among environmental exposures, cord blood cytokine responses, allergy, and wheeze at 1 year of age in an inner-city birth cohort (Urban Environment and Childhood Asthma study)

Psychosocial stress and asthma morbidity

PURPOSE OF REVIEW

The objective of this review is to provide an overview and discussion of recent epidemiologic and mechanistic studies of stress in relation to asthma incidence and morbidity.

RECENT FINDINGS

Recent findings suggest that stress, whether at the individual (i.e. epigenetics, perceived stress), family (i.e. prenatal maternal stress, early-life exposure, or intimate partner violence) or community (i.e. neighborhood violence; neighborhood disadvantage) level, influences asthma and asthma morbidity. Key recent findings regarding how psychosocial stress may influence asthma through Posttraumatic Stress Disorder, prenatal and postnatal maternal/caregiver stress, and community violence and deprivation are highlighted.

SUMMARY

New research illustrates the need to further examine, characterize, and address the influence of social and environmental factors (i.e. psychological stress) on asthma. Further, research and innovative methodologies are needed to characterize the relationship and pathways associated with stress at multiple levels to more fully understand and address asthma morbidity, and to design potential interventions, especially to address persistent disparities in asthma in ethnic minorities and economically disadvantaged communities.

Advances in pediatric asthma in 2011: moving forward

Last year's "Advances in pediatric asthma" concluded with the following statement: "Perhaps new directions in personalized medicine and improved health care access and communication will help maintain steady progress in alleviating the burden of this disease in children, especially young children." This year's summary will focus on recent advances in pediatric asthma that show significant accomplishments in reducing asthma morbidity and mortality over the last 10 years and discuss some pathways to further reduce asthma burden, as indicated in Journal of Allergy and Clinical Immunology publications in 2011. Some of the recent reports continue to shed light on methods to improve asthma management through steps to reduce asthma exacerbations, identify features of the disease in early childhood, alter asthma progression, intervene with nutrition, and more effectively implement the asthma guidelines. As new information evolves, it is also time to consider a revision of the asthma guidelines based on key studies that affect our management of the disease since the last revision in 2007. Now is also the time to use information recorded in electronic medical records to develop innovative disease management plans that will track asthma over time and enable timely decisions on interventions to maintain control that can lead to disease remission and prevention.

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.