The majority of infants with wheezing have transient conditions associated with diminished airway function at birth and do not have increased risks of asthma or allergies later in life. In a substantial minority of infants, however, wheezing episodes are probably related to a predisposition to asthma.

No abstract

Because most cases of asthma begin during the first years of life, identification of young children at high risk of developing the disease is an important public health priority. We used data from the Tucson Children's Respiratory Study to develop two indices for the prediction of asthma. A stringent index included frequent wheezing during the first 3 yr of life and either one major risk factor (parental history of asthma or eczema) or two of three minor risk factors (eosinophilia, wheezing without colds, and allergic rhinitis). A loose index required any wheezing during the first 3 yr of life plus the same combination of risk factors described previously. Children with a positive loose index were 2.6 to 5.5 times more likely to have active asthma between ages 6 and 13 than children with a negative loose index. Risk of having subsequent asthma increased to 4.3 to 9.8 times when a stringent index was used. We found that 59% of children with a positive loose index and 76% of those with a positive stringent index had active asthma in at least one survey during the school years. Over 95% of children with a negative stringent index never had active asthma between ages 6 and 13. We conclude that the subsequent development of asthma can be predicted with reasonable accuracy using simple, clinically based parameters.

Exposure of young children to older children at home or to other children at day care protects against the development of asthma and frequent wheezing later in childhood.

No abstract

Rationale: The effect of early life wheezing on respiratory function and continued symptoms through adolescence has not been fully described. Using data from a population-based birth cohort in Tucson, Arizona, we previously described four phenotypes based on the occurrence of wheezing lower respiratory illnesses before age 3 yr and active wheeze at age 6 yr: never wheezers (n ϭ 425), transient early wheezers (n ϭ 164), persistent wheezers (n ϭ 113), and lateonset wheezers (n ϭ 124). Objective: We sought to determine the prognosis for these phenotypes, with reference to lung function and symptoms, through adolescence. Methods: Current wheeze was assessed by questionnaire, lung function was measured by conventional spirometry, and atopy was determined by skin prick tests. Results: The prevalence of atopy and wheeze by age 16 yr was similar for never and transient wheezers and for persistent and late-onset wheezers. Both transient early, and persistent wheezers had significantly lower FEF 25-75 (-259 ml/s, p Ͻ 0.001, and -260 ml/s, p ϭ 0.001, respectively), FEV 1 (-75 ml, p ϭ 0.02, and -87 ml, p ϭ 0.03, respectively), and FEV 1 :FVC ratio (-1.9%, p ϭ 0.002, and -2.5%, p ϭ 0.001, respectively) through age 16 yr compared with never wheezers. Late-onset wheezers had levels of lung function similar to those of never wheezers through age 16 yr. There was no significant change in lung function among subjects with any of the four phenotypes, relative to their peers, from age 6 to 16 yr. Conclusion: Patterns of wheezing prevalence and levels of lung function are established by age 6 yr and do not appear to change significantly by age 16 yr in children who start having asthmalike symptoms during the preschool years.

Background-Together with smoking, the level of lung function attained in early adulthood is among the strongest predictors of chronic obstructive pulmonary disease. Whether airway function measured shortly after birth is a determinant of this level is currently unknown.

In a prospective study of 124 infants enrolled as newborns, we assessed the relation between initial lung function and the subsequent incidence of lower respiratory tract illness during the first year of life. The risk of having a wheezing illness was 3.7 times higher (95 percent confidence interval, 0.9 to 15.5; P = 0.06) among infants whose values for total respiratory conductance (the reciprocal of the resistance to air flow of the entire respiratory system) were in the lowest third, as compared with infants with values in the upper two thirds of the range of values for the group. Boys with initial values in the lowest third for an indirect index of airway conductance had a 10-fold increase (95 percent confidence interval, 2.2 to 44.2; P = 0.001) in the risk of having a wheezing illness. A 16-fold increase (95 percent confidence interval, 1.7 to 147.1; P = 0.002) in the risk of having a wheezing illness was found among girls whose initial values for lung volume at the end of tidal expiration were in the lowest third. We conclude that diminished lung function is a predisposing factor for the development of a first wheezing illness in infants.