Background: Change in airway resistance and inflammation are the two most commonly accused pathogenetic processes in the coexistence of asthma and obesity. The aim of this study was to compare airway resistance between normal weight and overweight/obese children using impulse oscillometry (IOS). Methods: We consecutively enrolled 3 to 10-year-old children with asthma who presented to our department between May and August 2018. Ones with a body mass index percentile at or above 85th percentile were grouped as overweight/obese. Sociodemographic characteristics such as age, sex and family history of allergy were recorded and Test for Respiratory and Asthma Control in Kids (TRACK) was filled in for all. Finally, impulse oscillometric (IOS) measurements were taken. Results: We enrolled 170 subjects; among which 114 (67.1%) were normal weight while 56 (33%) were overweight/obese. Sociodemographic characteristics were not significantly different between the two groups, but asthma control was significantly worse in the overweight/obese group (75.9±21.1 vs 85.9±17.8, p=0.001). Impulse oscillometric measurements of resistance and reactance were nor significantly different between the two groups. Conclusion: Asthma control in children who are overweight or obese are worse compared to the normal weight ones but, airway resistance and reactance measured by IOS at different frequencies are not significantly different between these two groups. This implies that airway resistance change may not the main pathogenetic mechanism underlying the uncontrolled asthma and obesity coexistence.

Background: Change in airway resistance and inflammation are the two most commonly accused pathogenetic processes in the coexistence of asthma and obesity. The aim of this study was to compare airway resistance between normal weight and overweight/obese children using impulse oscillometry (IOS). Methods: We consecutively enrolled 3 to 10-year-old children with asthma who presented to our department between May and August 2018. Ones with a body mass index percentile at or above 85th percentile were grouped as overweight/obese. Sociodemographic characteristics such as age, sex and family history of allergy were recorded and Test for Respiratory and Asthma Control in Kids (TRACK) was filled in for all. Finally, impulse oscillometric (IOS) measurements were taken. Results: We enrolled 170 subjects; among which 114 (67.1%) were normal weight while 56 (33%) were overweight/obese. Sociodemographic characteristics were not significantly different between the two groups, but asthma control was significantly worse in the overweight/obese group (75.9±21.1 vs 85.9±17.8, p=0.001). Impulse oscillometric measurements of resistance and reactance were nor significantly different between the two groups. Conclusion: Asthma control in children who are overweight or obese are worse compared to the normal weight ones but, airway resistance and reactance measured by IOS at different frequencies are not significantly different between these two groups. This implies that airway resistance change may not the main pathogenetic mechanism underlying the uncontrolled asthma and obesity coexistence.