1. Department of Pulmonary Medicine, Koç University School of Medicine, Istanbul 34450, Turkey
2. Department of Cardiology, Dokuz Eylül University Faculty of Medicine, Izmir 35340, Turkey
3. Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
4. Department of Clinical Sciences, Respiratory Medicine and Allergology, Faculty of Medicine, Lund University, 22185 Lund, Sweden
5. Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden