BACKGROUND/OBJECTIVES: Obesity is a global health problem that adversely influences the respiratory system. We assessed the effects of body mass index (BMI) on distal airway function and airway @entity32 . SUBJECTS/METHODS: Impulse oscillometry (IOS) as a measure of distal airway function, together with spirometry, were assessed in adults with a range of different BMIs. Airway @entity32 was assessed with the fraction of exhaled @entity842 (FeNO) and @entity1 exhaled at various exhalation flows to determine alveolar and bronchial NO. RESULTS: In total 34 subjects were enrolled in the study; 19 subjects had a normal BMI (18.50-24.99), whilst 15 subjects were overweight (BMI 25.00-29.99), or @entity28 (BMI >= 30). All subjects had normal spirometry. However, IOS measures of airway resistance (R) at 5Hz, 20Hz and frequency dependence (R5-20) were elevated in overweight/ @entity28 individuals, compared to subjects with a normal BMI (median (interquartile range)); 5Hz: 0.41 (0.37, 0.45) vs. 0.32 (0.30, 0.37)kPa/l/s; 20Hz: 0.34 (0.30, 0.37) vs. 0.30 (0.26, 0.33)kPa/l/s; R5-20: 0.06 (0.04, 0.11) vs. 0.03 (0.01, 0.05)kPa/l/s; p<0.05), whereas airway reactance at 20Hz was decreased in overweight/ @entity28 individuals (20Hz: 0.07 (0.03, 0.09) vs. 0.10 (0.07, 0.13)kPa/l/s, p=0.009; 5Hz: -0.12 (-0.15, -0.10) vs. -0.10 (-0.13, -0.09)kPa/l/s, p=0.07). In contrast, within-breath IOS measures (a sign of expiratory flow limitation) and FeNO inflammatory measures, did not differ between groups (p>0.05). CONCLUSIONS: Being overweight has significant effects on distal and central airway function as determined by IOS, which is not detected by spirometry. Obesity does not influence airway @entity32 as measured by FeNO. IOS is a reliable technique to identify airway abnormalities in the presence of normal spirometry in overweight @entity1 .

The effect of body weight on distal airway function and airway XXXX .

@entity1 :: ('9606', 'Species') :: ['participants', 'people'] @entity32 :: ('MESH:D007249', 'Disease') :: ['inflammation'] @entity842 :: ('MESH:D009569', 'Chemical') :: ['nitric oxide'] @entity28 :: ('MESH:D009765', 'Disease') :: ['obese']
@entity32 :: (MESH:D007249,Disease) :: ['inflammation']
