Lung sound analysis for predicting recurrent wheezing in preschool children

Abstract

BackgroundIn young healthy children, assessing airflow limitation may be difficult because of the narrowing of the airways, which is a pathology of asthma, and responsiveness to bronchodilators. ObjectiveWe investigated whether lung sound analysis could predict the development of recurrent wheezing (RW), one of the signs of asthma. MethodsIn healthy children aged 3 to 24 months, we recorded and analyzed lung sounds before and after inhalation of bronchodilators and conducted a questionnaire survey. The children were followed up and assessed for the development of RW at 3 years of age. ResultsOf the 62 patients analyzed, 19 (30.6%) developed RW. The parameters RPF50 and RPF75, calculated by lung sound analysis, were lower in the RW group, with odds ratios (95% CI) of 0.77 (0.61–0.98) and 0.81 (0.66–0.99), respectively. The change rate of lung sound analysis parameters after bronchodilator inhalation was not different among all participants; however, in the subgroup of children with a history of atopic dermatitis, B4/AT and ΔRPF50 were elevated in the RW group (P = .015 and P = .041, respectively). In the subgroup of children with total IgE >20 kUA/L, the sensitivity and specificity (95% CI) for predicting the development of RW were 85.7% (48.7-99.3) and 68.8% (44.4-85.8), respectively, when the cutoff value of ΔRPF50 was set at 10.5%. ConclusionThe lung sound analysis method allows noninvasive assessment of the airway, including airway hypersensitivity, in young children and may predict the risk of developing RW.