Effects of body weight and posture on pulmonary functions in asthmatic children

Background: Asthma is one of the most common chronic illnesses in the world. Pulmonary function tests are important tools in monitoring of asthmatic patients. There is need for investigating if spirometric indices were affected by body weight or posture or not.
Objectives: The aim of this study was to evaluate the spirometric measurements in standing and sitting positions in a group of Egyptian asthmatic children with different body weights.
Methods: Sixty patients were included. They were stable asthmatics and were following up in the allergy clinic. Spirometry was conducted at pulmonary functions laboratory of Pediatric Allergy and Chest Unit of New Children’s University Hospital, Cairo. The one-way analysis of variance was used to test the differences between groups. The Duncan multiple comparison test was used to test the significant differences between each pair of groups.
Results: The study found that sitting FEV1/FVC is significantly lower in overweight/obese asthmatic children compared to normal weight asthmatic children (p value=0.046).
Conclusion: There was no effect of weight on standing spirometric data. Weight showed significant negative correlation with asthma control level. We concluded that in overweight/obese asthmatic children, spirometric position might affect the results.