**Acknowledgements**

The authors thank Dr. Joseph Milic-Emili for valuable input to the manuscript; Mr. Louis Wilkinson for his valuable technical assistance; Dr. Danielle Kushner and Mr. Shadman Chowdhury for assistance in tabulating data. Dr. Cheryl Vigen and Dr. Zhanghua Chen pro‐ vided critical statistical and data analysis. The authors also thank the technical staff of the Pulmonary Function Laboratory at Los Angeles County + University of Southern California Medical Center for performing the lung function and polysomnograhic testing, and all the patients and volunteers who participated in the study.
