Jade M Murray1, Andrew J K Phillips2, Michelle Magee1, Tracey L Sletten1, Christopher Gordon3, Nicole Lovato4, Bei Bei5, Delwyn J Bartlett6, David J Kennaway7, Leon C Lack4, Ronald R Grunstein6, Steven W Lockley8, Shantha M W Rajaratnam8. 1. School of Psychological Sciences, Monash University, Clayton, Victoria, Australia; Cooperative Research Centre for Alertness, Safety and Productivity, Clayton, Victoria, Australia; NHMRC Centre for Sleep and Circadian Neurobiology, Sydney, New South Wales, Australia. 2. School of Psychological Sciences, Monash University, Clayton, Victoria, Australia. Electronic address: andrew.phillips@monash.edu. 3. Cooperative Research Centre for Alertness, Safety and Productivity, Clayton, Victoria, Australia; NHMRC Centre for Sleep and Circadian Neurobiology, Sydney, New South Wales, Australia; Woolcock Institute of Medical Research and Sydney Local Health District, Sydney, New South Wales, Australia; University of Sydney Susan Wakil School of Nursing, New South Wales, Australia. 4. Cooperative Research Centre for Alertness, Safety and Productivity, Clayton, Victoria, Australia; Adelaide Institute for Sleep Health, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia. 5. School of Psychological Sciences, Monash University, Clayton, Victoria, Australia. 6. Cooperative Research Centre for Alertness, Safety and Productivity, Clayton, Victoria, Australia; NHMRC Centre for Sleep and Circadian Neurobiology, Sydney, New South Wales, Australia; Woolcock Institute of Medical Research and Sydney Local Health District, Sydney, New South Wales, Australia. 7. Robinson Research Institute and School of Medicine, University of Adelaide, Adelaide, South Australia, Australia. 8. School of Psychological Sciences, Monash University, Clayton, Victoria, Australia; Cooperative Research Centre for Alertness, Safety and Productivity, Clayton, Victoria, Australia; NHMRC Centre for Sleep and Circadian Neurobiology, Sydney, New South Wales, Australia; Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA.
Abstract
BACKGROUND: In healthy populations, irregular sleep patterns are associated with delayed sleep and poor functional/mood outcomes. Currently, it is unknown whether irregular sleep contributes to poor functional/mood outcomes in individuals with Delayed Sleep-Wake Phase Disorder (DSWPD). METHODS: In 170 patients with DSWPD, we collected sleep-wake patterns, dim light melatonin onset (DLMO), and functional/mood outcomes. The Sleep Regularity Index (SRI) and other sleep timing metrics were computed. Correlations of SRI were computed with phase angle (difference between DLMO and desired bedtime), sleep timing and quality variables, daytime function, sleep-related daytime impairment, mood, and insomnia symptom severity. Path analyses assessed whether SRI or total sleep time mediated the associations between sleep onset time and phase angle with daytime functioning, sleep-related impairment, and mood outcomes. RESULTS: Higher SRI was associated with earlier sleep and longer total sleep time, but did not relate to sleep quality, daytime function, or mood outcomes. Path analysis showed that phase angle was directly associated with all outcome variables, whereas sleep onset time was not directly associated with any. SRI mediated the effects of sleep onset time and phase angle on daytime function. Total sleep time mediated the effects of sleep onset time and phase angle on sleep-related impairment. CONCLUSION: Individuals with DSWPD who have more delayed sleep and a greater phase angle also have more irregular sleep. This suggests that it is not delayed sleep timing per se that drives poor functional outcomes in DSWPD, but rather the timing of sleep relative to circadian phase and resultant irregular sleep patterns.
BACKGROUND: In healthy populations, irregular sleep patterns are associated with delayed sleep and poor functional/mood outcomes. Currently, it is unknown whether irregular sleep contributes to poor functional/mood outcomes in individuals with Delayed Sleep-Wake Phase Disorder (DSWPD). METHODS: In 170 patients with DSWPD, we collected sleep-wake patterns, dim light melatonin onset (DLMO), and functional/mood outcomes. The Sleep Regularity Index (SRI) and other sleep timing metrics were computed. Correlations of SRI were computed with phase angle (difference between DLMO and desired bedtime), sleep timing and quality variables, daytime function, sleep-related daytime impairment, mood, and insomnia symptom severity. Path analyses assessed whether SRI or total sleep time mediated the associations between sleep onset time and phase angle with daytime functioning, sleep-related impairment, and mood outcomes. RESULTS: Higher SRI was associated with earlier sleep and longer total sleep time, but did not relate to sleep quality, daytime function, or mood outcomes. Path analysis showed that phase angle was directly associated with all outcome variables, whereas sleep onset time was not directly associated with any. SRI mediated the effects of sleep onset time and phase angle on daytime function. Total sleep time mediated the effects of sleep onset time and phase angle on sleep-related impairment. CONCLUSION: Individuals with DSWPD who have more delayed sleep and a greater phase angle also have more irregular sleep. This suggests that it is not delayed sleep timing per se that drives poor functional outcomes in DSWPD, but rather the timing of sleep relative to circadian phase and resultant irregular sleep patterns.
Authors: Lauren A Watson; Elise M McGlashan; Ihaia T Hosken; Clare Anderson; Andrew J K Phillips; Sean W Cain Journal: J Clin Sleep Med Date: 2020-09-15 Impact factor: 4.062
Authors: Jade M Murray; Michelle Magee; Tracey L Sletten; Christopher Gordon; Nicole Lovato; Krutika Ambani; Delwyn J Bartlett; David J Kennaway; Leon C Lack; Ronald R Grunstein; Steven W Lockley; Shantha M W Rajaratnam; Andrew J K Phillips Journal: Sci Rep Date: 2021-05-25 Impact factor: 4.379
Authors: Stephanie Griggs; Kingman P Strohl; Margaret Grey; Eric Barbato; Seunghee Margevicius; Ronald L Hickman Journal: Chronobiol Int Date: 2021-06-15 Impact factor: 3.749
Authors: Jessica R Lunsford-Avery; Katherine S F Damme; Matthew M Engelhard; Scott H Kollins; Vijay A Mittal Journal: Sci Rep Date: 2020-01-16 Impact factor: 4.379
Authors: Alyssa T Brooks; Shravya Raju; Jennifer J Barb; Narjis Kazmi; Subhajit Chakravorty; Michael Krumlauf; Gwenyth R Wallen Journal: Int J Environ Res Public Health Date: 2020-01-03 Impact factor: 3.390