1. Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
2. Interdisciplinary Sleep Medicine Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
3. Saratov State University, Saratov, Russian Federation
4. Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
5. Department of Internal Medicine B, University Medicine Greifswald, Greifswald, Germany
6. Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany