Received: 18 March 2019
Accepted: 29 May 2019
First Online: 7 June 2019
Ethics approval and consent to participate
: This study was performed at the Department of Respiratory Medicine at St. Marianna University School of Medicine Hospital, with ethics approval (human research and ethics committee approval reference number 3590) and registered as a clinical trial UMIN000027030. In this study, written informed consent was obtained from all participants.
: Not applicable.
: The authors have no financial or commercial associations that would be considered a conflict of interest in relation to this study.