1. Department of Molecular and Clinical Medicine; Sahlgrenska Academy/Sahlgrenska Academy Hospital; University of Gothenburg; Gothenburg Sweden
2. Skaraborg Hospital; Skövde Sweden
3. Department of Cardiology; Beijing Hospital; National Center of Gerontology; Beijing China
4. Department of Molecular Medicine and Surgery; Clinical Physiology; Karolinska Institutet; Stockholm Sweden
5. Center for Sleep and Vigilance Disorders; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden