[1] Univ Edinburgh, Ctr Clin Brain Sci, Sleep Res Unit, Edinburgh, Midlothian, Scotland
[2] Univ Edinburgh, Ctr Clin Brain Sci, EPAD, Edinburgh, Midlothian, Scotland
[3] Royal Infirm Edinburgh NHS Trust, Dept Sleep Med, 51 Little France Crescent, Edinburgh EH16 4SA, Midlothian, Scotland