Lung function in school-age children who had mild lower respiratory illnesses in early childhood.

We examined the relationship between patterns of mild lower respiratory illness (LRI) experienced in early childhood and lung function in 89 boys and 70 girls 6 to 18 yr of age. The children's histories of outpatient visits for wheezing and nonwheezing LRI during the first 6 yr of life had been documented by physicians in a single pediatric practice. Most children were reported by their parents to have been free of recurrent respiratory symptoms during the 2 yr prior to lung function testing. In sex-specific analyses, average lung function assessed by spirometry was similar in children who had made zero or one physician visit for wheezing LRI during the preschool years. Boys who had experienced two or more episodes of wheezing LRI during the preschool years had lower average FEV1, FEV1/FVC, FEF25-75, Vmax50, and Vmax75 than did boys who had zero or one preschool wheezing illness. The association between recurrent preschool wheezing LRI and later lung function remained after exclusion of data from seven boys who were reported to have wheezed in the 2 yr prior to study. Girls who had experienced two or more preschool wheezing LRI had lower average FEF25-75 and Vmax50 than girls with a history of zero or one such illness, but differences were not statistically significant. Recurrent nonwheezing LRI during the preschool years was not significantly associated with subsequent lung function in either sex, regardless of preschool wheezing LRI history. Detailed information concerning early childhood LRI experience is valuable in epidemiologic studies of factors influencing lung function in children.

Correlates of recurrent wheezing in school-age children. The Physicians of Raleigh Pediatric Associates.

Correlates of recurrent wheezing were examined in a case-control study involving 343 children ranging from 7 to 12 yr of age and recruited from a general pediatric practice. Positive skin tests for allergy were observed in 35% of a random sample of children without recurrent wheezing, and in 77% and 90% of children who had experienced from two to four episodes and five or more episodes, respectively, of recent wheezing. By logistic regression analysis, sensitization to dust mite (odds ratio [OR]: 5.2; 95% CI: 3.0 to 9.0), cat (OR: 15.5; 95% CI: 3.4 to 70.8), and Alternaria (OR: 6.8; 95% CI: 2.1 to 21.5) antigens was consistently associated with recurrent wheezing. Sensitization to pollen antigen(s), observed in 60% of allergic children, was not associated with wheezing. A family history of asthma was a significant predictor of recurrent wheezing (OR: 3.2; 95% CI: 1.7 to 5.9) after adjusting for its association with positive skin tests. Environmental tobacco smoke (ETS) exposure was associated with an increased risk of recurrent wheezing in nonallergic children and in allergic females, but not in allergic males. ETS exposure was not associated with positive skin tests for allergy. A history of wheezing with respiratory illness before 2 yr of age was associated with a modest risk of recurrent wheezing between 7 and 12 yr of age (OR: 2.3; 95% CI: 1.2 to 4.6), a risk that did not differ by allergic status or gender. Theoretically, the prevalence of recurrent wheezing in this population could be reduced approximately 65% by controlling exposure to indoor allergens and ETS.

Respiratory allergy and the relationship between early childhood lower respiratory illness and subsequent lung function.

In a study of 159 school-age children whose histories of outpatient visits for lower respiratory illness (LRI) had been documented from early infancy, we observed lower mean levels of small airway function in boys who had experienced two or more episodes of wheezing-associated LRI before 6 yr of age. To determine whether allergy was an important factor influencing this result, we examined relationships among the results of RAST tests for seven common inhalant allergens and concurrent lung function in 126 subjects who consented to venipuncture. Increasing values for the sum of scores for the seven RAST tests were associated with progressively lower mean levels of small airways function in boys with histories of recurrent wheezing LRI during the preschool years. The association of allergy with lower levels of lung function was largely accounted for by dust mite allergy. RAST results were not correlated with lung function in boys who had experienced zero or 1 wheezing LRI before 6 yr of age or in girls. A history of recurrent wheezing LRI during the preschool years was also associated with significantly lower mean levels of small airways function in boys who had negative RAST tests. A subset of 49 boys was reevaluated after an average interval of 4 yr with RAST tests, spirometry, and methacholine challenge. Dust mite allergy was associated with an increased prevalence of bronchial hyperreactivity independent of early childhood wheezing LRI history.(ABSTRACT TRUNCATED AT 250 WORDS)