Risk factors for asthma symptoms at school age: An 8-year prospective study

Abstract

Childhood recurrent wheezing is a very prevalent heterogeneous clinical entity. An 8-year prospective study was performed to correlate the clinical outcome of recurrent wheezing in the first years of life with prognostic risk factors. A cohort of 308 children with recurrent wheezing, aged <7 years, were enrolled in 1993, studied using a questionnaire, skin-prick tests, and serum total IgE. According to the study protocol, in 1996 and 2001, the cohort was assessed. In 2001, 81% of the initial sample was reevaluated (n=249); 61% remained symptomatic. Prevalence of atopy was 48% in 1993, 65% in 1996, and 75% in 2001. By logistic regression analysis, we identified the following as independent risk factors for asthma symptoms in the last year of the follow-up: personal history of rhinitis (odds ratio [OR] = 15.8, 95% confidence interval [CI], 6.1-40.8; p < 0.001), paternal asthma (OR =, 7.2; 95% CI = 1.7-29.7; p = 0.007), personal history of atopic dermatitis (OR = 5.9, 95% CI = 2.2-15.7; p < 0.001), maternal asthma (OR = 5.4, 95% CI = 1.7-17.1; p = 0.004), allergen sensitization (OR = 3.4, 95% CI = 1.2-10.4; p = 0.03), and onset of symptoms in the 2nd year or later in preschool-aged children (OR = 2.1, 95% CI = 1.1-4.8; p = 0.04). Kindergarten attendance before 12 months was identified as a protective factor (OR = 0.4, 95% CI = 0.2-0.9; p = 0.04). Among the 128 nonatopic children in 1993, 52% developed allergen sensitization. We identified as prognostic risk factors for asthma symptoms personal history of allergic disease, parental asthma, atopy, and late onset of symptoms. In a significant number of children clinical symptoms can occur years before allergen sensitization.

Clinical assessment of asthma progression in children and adults

“…Children with a positive loose API were 5.5 times whereas those with a positive stringent API were 9.8 times more likely to have asthma at some time during the school years compared with those with a negative API. With that said, the positive predictive value for active asthma at least once during follow-up was only 59% in children with a positive loose index 2,21,23,24 Onset of wheezing after 2 years of age 5,23 RSV bronchiolitis requiring hospitalization in the first year of life [27][28][29] Asthma Predictive Index 2, 21 One major criterion (parent with asthma, concurrent atopic dermatitis) or Two minor criteria (wheezing apart from colds, eosinophilia, food sensitization) and 76% in those with a stringent positive index. The high negative predictive values and specificity (>80%) for both indices suggest that the majority of preschool children with recurrent wheeze and a negative API are not at increased risk of having asthma in school age.…”

“…These include female sex, 14,16,[39][40][41] BHR in adulthood, 14,16 and personal or family history of atopy. 39,41 Symptom severity, lung function in childhood, and onset of symptoms after the age of 2 years 5,23,39,42,43 are also related to outcome in adulthood.…”

Is parent–child bed-sharing a risk for wheezing and asthma in early childhood?

“…Child inhalant allergy did attenuate the effect of bed-sharing at 24 months on asthma diagnosis, but it did not attenuate the effect on the repeated wheezing measures or the persistent wheezing phenotype. A history of inhalant allergy is an important risk factor for development of childhood asthma [40,41], and our findings suggest that atopy could affect the development of asthma in bed-sharing families. However, previous studies also indicate that multiple features may interact in the expression of early wheezing, and the combination of these features (e.g.…”

“…Many demographic and environmental factors also affect the development of childhood wheezing and asthma [41], and must be taken into account when modelling associations with family and crowding factors. In the first model, a small set of confounders was used, but even when controlling for a comprehensive set of confounders (as in the second model), the effect estimates remained significant, indicating a robust association between bed-sharing in toddlerhood and development of asthma.…”

Epidemiology of asthma and allergic diseases in Portuguese speaking regions

“…The authors [14] performed an 8-year prospective study, in order to correlate clinical outcome of recurrent wheezing in the first years of life with prognostic risk factors, including evaluation of the impact of allergic rhinitis. A cohort of 308 children with recurrent wheezing, aged less than 7 years, was enrolled in 1993, studied with clinical questionnaire (adapted from ISAAC), skin prick tests (standardised allergen extracts to common inhalant allergens, house-dust mites, pollens, moulds, cockroaches and pets supplied by Merck-AlIergopharma and CBF-Leti, and food allergens, cow's milk proteins, egg, fish and wheat supplied by Stallergènes), and serum total IgE.…”