1. Department of CardiologyLovisenberg Diakonale Hospital Norway
2. Unit of Sleep MedicineLovisenberg Diakonale Hospital Norway
3. Department of BiostatisticsOslo University Hospital UllevalOslo Norway
4. Department of CardiologyOslo University Hospital UllevalOslo Norway
5. Department of Surgery and Clinical NeuroscienceOslo University Hospital Rikshospitalet and University of OsloOslo Norway