Airway resistance in irritable bowel syndrome as measured by impulse oscillometry

Irritable bowel syndrome (IBS) is associated with bronchial asthma. However, published data on airway resistance or impedance in patients with IBS but without any respiratory symptoms are lacking.

Patients with IBS but no respiratory symptoms underwent spirometry and airway resistance measurement using impulse oscillometry; the data were compared with those from 97 historical age- and sex-matched healthy control subjects.

Patients had lower FEV1 (3.03 [0.74] vs. 3.35 [0.80] L/min; p=0.004) and FVC (3.56 [0.85] vs. 3.88 [0.9]; p=0.01) than healthy subjects; however, the values were within the normal range. Patients had a higher resistance at 5 Hz (0.45 [0.42] vs. 0.30 [0.15] kPa L/s; p=0.003); however, reactance at this frequency was not significantly different (-0.08 [0.30] vs. -0.10 [0.09] kPa L/s; p=0.438).

Patients with IBS have increased airway resistance as compared to healthy subjects, as measured by impulse oscillometry; however, reactance is unchanged, indicating no change in elastic resistance.