Methacholine and Macrolides

study are relevant, I believe that the design of the study was not adequate to answer these questions. First, all patients were on NM for w3 months and one patient even for 70 months, whereas they trained only for 1 day on FFM. In our centre (Dept of Pulmonary Diseases/ Home mechanical ventilation, University Hospital Groningen, Groningen, The Netherlands), patients routinely need more time (y7 days) to adjust to their specific mask. As a result of this short time of training on FFM compared with a long-term adjustment on NM, it is not surprising that total sleep time and sleep efficiency were worse in the FFM group compared with the NM group. As a consequence of their longer experience with the NM mask, the patients also rated less leak and more comfort in the NM night compared with the FFM night. Secondly, no differences were found between pressure settings if NM was compared with FFM. However, this study will not detect any differences if pressure settings, optimalised during their review night, remained unchanged during the subsequent mask trials. Due to the previously mentioned issues, I believe that the study by WILLSON et al. [1], with its present design, makes it difficult to draw strong conclusions. It would have been preferable to compare both mask ventilations in a parallel study of naı̈ve patients in whom noninvasive ventilation was started. In this way, it would have been possible to compare the time it takes to adjust to either nasal mask or full face mask. If the patients were adjusted to the mask, it would be possible to determine differences in terms of sleep quality, tolerability and pressure needed to maintain an effective noninvasive ventilation.