Test radioaerosol penetration into the lungs increased significantly ( p < 0.003 ) as did FEV1 ( p < 0.006 ) in the tiotropium-treated patients , but measured mucociliary clearance was not significantly changed despite the increased pathway length for clearance ( mean + / - SE area under the tracheobronchial retention curve changed from 442 + / - 22 to 453 + / - 20 % / h ) .
