TY - JOUR
T1 - Circadian phase and phase angle disorders in primary insomnia
AU - Flynn-Evans, Erin E.
AU - Shekleton, Julia A.
AU - Miller, Belinda
AU - Epstein, Lawrence J.
AU - Kirsch, Douglas
AU - Brogna, Lauren A.
AU - Burke, Liza M.
AU - Bremer, Erin
AU - Murray, Jade M.
AU - Gehrman, Philip
AU - Rajaratnam, Shantha M.W.
AU - Lockley, Steven W.
N1 - Funding Information:
EEF reports that she is a consultant for Baby Sleep Science. JAS, BRM, LAB, LMB, EB, JMM, DK, and PG report no conflicts of interest in relation to this study. SMWR reports that he has served as a consultant through his institution to Vanda Pharmaceuticals, Philips Respironics, EdanSafe, The Australian Workers’ Union, National Transport Commission, Transport Accident Commission, New South Wales Department of Education and Communities, and has through his institution received research grants and/or unrestricted educational grants from Vanda Pharmaceuticals, Shell, Teva Pharmaceuticals, Rio Tinto, Seeing Machines, Takeda Pharmaceuticals North America, Philips Lighting, Philips Respironics, Cephalon, and ResMed Foundation, and reimbursements for conference travel expenses from Vanda Pharmaceuticals. His institution has received equipment donations or other support from Optalert™, Compumedics, and Tyco Healthcare. He has served as an expert witness and/ or consultant to shift work organizations. Prof Rajaratnam also serves as a Program Leader in the Cooperative Research Centre for Alertness, Safety and Productivity. In the last 12 months, SWL has received consulting fees from the Atlanta Falcons, Atlanta Hawks, BHP Billiton and Slingshot Insights; has current consulting contracts with Akili Interactive; Consumer Sleep Solutions; Delos Living LLC; Environmental Light Sciences LLC; Headwaters Inc.; Hintsa Performance AG; Light Cognitive; Mental Workout; OpTerra Energy Services Inc.; Pegasus Capital Advisors LP; PlanLED; and Wyle Integrated Science and Engineering; has received unrestricted equipment gifts from Biological Illuminations LLC, Bionetics Corporation and F. Lux Software LLC; royalties from Oxford University Press; and has served as a paid expert in legal proceedings related to light, sleep and health. He holds a patent through Harvard University and Brigham and Women’s Hospital for “Systems and methods for determining and/or controlling sleep quality.” He is a Program Leader for the CRC for Alertness, Safety and Productivity, Australia.
Funding Information:
We would like to thank Elizabeth Lydon for assistance with this study and Melissa St. Hilaire, PhD for assistance with the phase angle definitions. The study was funded by an investigator-initiated research grant from Philips Respironics to the Brigham and Women’s Hospital (PI: Lockley; Co-Is: Rajaratnam, Epstein).
PY - 2017/12/1
Y1 - 2017/12/1
N2 - Objectives: We aimed to identify the prevalence of circadian phase and phase angle abnormalities in patients with insomnia. Methods: We conducted a cross-sectional, multicenter study at three sleep laboratories in the United States and Australia. Patients with insomnia and healthy control participants completed a sleep log for 7 days. Circadian phase was assessed from salivary dim light melatonin onset (DLMO) time during a 12-hour laboratory visit. Results: Seventy-nine patients meeting the Research Diagnostic Criteria for Primary, Psychophysiological, Paradoxical, and/or Idiopathic Childhood Insomnia (46 females, 35.5 ± 12.3 years [M ± SD]) and 21 controls (14 females, 34.4 ± 11.8 years). As compared to controls, patients with insomnia tried to initiate sleep on average at the same clock time (24:17 ± 1:17 hours vs. 24:13 ± 1:30 hours, respectively; p = .84) but had a later average DLMO times (20:56 ± 1:55 hours, 18:17–01:21 vs. 22:02 ± 2:02 hours, 17:11–04:52, respectively; p = .04). Consequently, patients with insomnia slept at an earlier circadian phase than controls (phase angle, bedtime-DLMO 2:13 hours (± 1:43) vs. 3:10 hours (± 1:08), respectively; p = .008), of whom 10% tried to sleep at or before DLMO (compared to 0 controls), and 22% tried to sleep before or within 1 hour after DLMO (compared to 6% of controls). Conclusions: A substantial proportion (10%–22%) of patients with insomnia initiate sleep at too early a circadian phase, implicating a circadian etiology for their insomnia. Outpatient circadian phase assessments should be considered to improve differential diagnoses in insomnia and to inform the development of appropriately timed circadian-based treatments.
AB - Objectives: We aimed to identify the prevalence of circadian phase and phase angle abnormalities in patients with insomnia. Methods: We conducted a cross-sectional, multicenter study at three sleep laboratories in the United States and Australia. Patients with insomnia and healthy control participants completed a sleep log for 7 days. Circadian phase was assessed from salivary dim light melatonin onset (DLMO) time during a 12-hour laboratory visit. Results: Seventy-nine patients meeting the Research Diagnostic Criteria for Primary, Psychophysiological, Paradoxical, and/or Idiopathic Childhood Insomnia (46 females, 35.5 ± 12.3 years [M ± SD]) and 21 controls (14 females, 34.4 ± 11.8 years). As compared to controls, patients with insomnia tried to initiate sleep on average at the same clock time (24:17 ± 1:17 hours vs. 24:13 ± 1:30 hours, respectively; p = .84) but had a later average DLMO times (20:56 ± 1:55 hours, 18:17–01:21 vs. 22:02 ± 2:02 hours, 17:11–04:52, respectively; p = .04). Consequently, patients with insomnia slept at an earlier circadian phase than controls (phase angle, bedtime-DLMO 2:13 hours (± 1:43) vs. 3:10 hours (± 1:08), respectively; p = .008), of whom 10% tried to sleep at or before DLMO (compared to 0 controls), and 22% tried to sleep before or within 1 hour after DLMO (compared to 6% of controls). Conclusions: A substantial proportion (10%–22%) of patients with insomnia initiate sleep at too early a circadian phase, implicating a circadian etiology for their insomnia. Outpatient circadian phase assessments should be considered to improve differential diagnoses in insomnia and to inform the development of appropriately timed circadian-based treatments.
KW - 6-sulfatoxymelatonin
KW - Circadian
KW - Circadian rhythms
KW - DLMO
KW - Insomnia
KW - Melatonin
KW - Phase angle
UR - http://www.scopus.com/inward/record.url?scp=85040726841&partnerID=8YFLogxK
U2 - 10.1093/sleep/zsx163
DO - 10.1093/sleep/zsx163
M3 - Article
C2 - 29029340
AN - SCOPUS:85040726841
SN - 0161-8105
VL - 40
JO - Sleep
JF - Sleep
IS - 12
M1 - Y
ER -