Asthma predictive index in relation to respiratory mechanics by impulse oscillometry in recurrent wheezers.

BACKGROUND: The identification of children who will have persistent asthma has become a focus of recent research. The aim of this study was to assess whether impulse oscillometry (IOS) has a diagnostic value to predict modified API (asthma predictive index) in pre-schoolers with recurrent wheezing.

METHODS: Pre-school children aged 3-6 years with recurrent wheezing were enrolled. The study population was divided into two groups based on mAPI criteria. Lung function was assessed by IOS.

RESULTS: 115 children were assessed; 75 (65.2%) of them were male. The median age was 39 months (min: 36, max: 68 months). 64 (55.6%) of the children were mAPI positive. The R5-R20% levels of children with positive mAPI were significantly higher compared to negative mAPI. Also, R5-R20% levels of children with parental asthma and R20% pred and resonant frequency (Fres) levels of children with inhalant sensitization were higher than those without. No significant differences were found in IOS indices between groups based on the presence of atopic dermatitis, food sensitization, eosinophilia, inhaled corticosteroid usage or wheezing without colds. R5-R20% and total IgE values were found to be significantly related to positive mAPI (aOR: 1.40, p=0.022 and aOR: 1.02, p=0.001, respectively). In the ROC analysis, R5-R20% levels >14.4 had a sensitivity of 75% and specificity of 53% for predicting a positive mAPI (p=0.003).

CONCLUSION: IOS may help clinicians to identify the pre-school wheezers with a high risk of asthma.