1. Department of Mountain and Sleep Medicine and Pulmonary Hypertension, National Center of Cardiology and Internal Medicine, Bishkek, Kyrgyzstan.
2. Kyrgyz-Indian Mountain Biomedical Research Center, Bishkek, Kyrgyzstan.
3. Department of Internal Medicine, Excellence Cluster Cardio-Pulmonary System (ECCPS), Justus Liebig University of Giessen, Giessen, Germany.