Effect of an inhaled glucocorticosteroid on airway mucosal blood flow in mild asthma.

We determined airway mucosal blood flow (Qaw) and FEV (1) before and after inhaled albuterol in 19 glucocorticosteroid (GS)-naive patients with mild intermittent asthma, and assessed the effects of a 2-wk course of fluticasone propionate (FP; 440 microg daily) on these parameters. Twelve healthy nonsmokers served as controls. Baseline Qaw was 55.5 +/- 0.7 microl/min/ml (mean +/- SE) in the asthmatic subjects and 44.2 +/- 0.7 microl/min/ml in the controls; the respective FEV(1) values were 2.8 +/- 0.2 L and 3.4 +/- 0.2 L (p < 0.01 for both parameters). Albuterol increased Qaw by 27 +/- 3% in the control subjects (p < 0.01) but had no effect on Qaw in the asthmatic subjects; it increased FEV (1) by 7 +/- 1% and 6 +/- 1% in the two groups, respectively. Qaw decreased to 49.2 +/- 0.8 microl/min/ml (p < 0.05 versus baseline), and the Qaw responsiveness to albuterol was restored ( +21 +/- 2%; p < 0.05) in the asthmatic subjects after FP. Eleven asthmatic subjects stopped using FP at this time; 2 wk later, their Qaw returned to baseline (55.2 +/- 0.9 microl/min/ml) and they lost the Qaw responsiveness to albuterol. Mean ( +/- SE) FEV(1) and FEV(1) responsiveness to albuterol were not affected by FP. The GS-sensitive increase in Qaw and its hyporesponsiveness to albuterol in asthmatic subjects may be consequences of airway inflammation.