Abstract
Background: The role of elevated BMI in asthma is controversial.
Objectives: To investigate the relationship between overweight (BMI > 25 < 30 kg/m²) and total, proximal and peripheral airway resistance, by means of IOS in asthmatic patients as compared to controls.
Methods: In 62 asthmatics (35 F; age 42 yr ± 15) with normal spirometry (FEV1/FVC≥70% and FEV1≥80%) and BMI < 30 kg/m2 and 38 healthy subjects (22 F; age yr 36 ± 12), respiratory resistance at 5 and 20 Hz and the fall in resistance from 5 to 20 Hz (R5, R20 and R5-R20, in kPa s l-1) were measured as indices of total, proximal and peripheral airway resistance, respectively.
Results: In all subjects and in asthmatic patients and healthy controls, when separately assessed, BMI was significantly related (p<0.01) to R5-R20, but not to R5 and R20 values. Moreover, R5-R20 values, but not R5 and R20 values were significantly higher (p<0.05) in overweight as compared to normal weight (BMI > 20 ≤ 25 kg/m²) asthmatic and healthy subjects.
Conclusions: This study shows that overweight is strictly associated to small airway dysfunction both in asthma and in normal people. IOS may add further information to spirometry in asthma.
- © 2013 ERS