Pulmonary function is reduced in children with recurrent wheezing irrespective of Asthma Predictive Index results

Objective: It is important to determine the risk factors for the development of asthma in patients with recurrent wheezing (RW). This study was intended to compare the lung functions of children with RW with and without Asthma Predictive Index (API) positivity. Methods: This prospective cross-sectional study included 40 children with RW aged between 3 months and 3 years and 34 age- and sex-matched healthy controls (HC). Lung functions were measured using tidal breath analysis during the wheezing attack in the RW group. Peak tidal expiratory flow time (TPTEF), ratio of peak tidal expiratory flow time to expiratory time (TPTEF/TE), volume required for PTEF (VPTEF), ratio of volume required for PTEF to expiratory volume (VPTEF/VE), tidal volume/kg (VT/kg), inspiratory to expiratory ratio (TI/TE), inspiratory time (TI), and expiratory time (TE) represented the main tidal breath analysis parameters. API positivity was also calculated in the RW group. Results: TPTEF, VPTEF, TPTEF/TE, VPEF/VE, TI, and TI/TE were all lower in the RW group than in the HC group (p<0.05). However, there was no difference in TPTEF/TE between the RW patients with positive and negative API. TPTEF and TE parameters were higher in the RW group with positive API (p=0.026 and p=0.043, respectively). Conclusion: Greater bronchial obstruction was observed in the RW group compared to the HC group. No difference in bronchial obstruction was detected between the RW group with positive API and the negative API group. API positivity during wheezing attacks did not emerge as an important parameter in terms of decreased lung functions in this study.