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Published on: October 2, 2019
Delayed Sleep-Wake Phase Disorder: Can Polysomnography Be Useful?
Iva Příhodová1, Simona Dostálová1, Petr Bielicki2
1Department of Neurology and Center for Clinical Neurosciences, 1(st) Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic.
Delayed sleep-wake phase disorder in adolescents is common, but polysomnography confirms sleep delay in only 38%. Psychiatric comorbidities like ADHD and mood disorders are frequent in these patients.
Area of Science:
- Sleep Medicine
- Adolescent Health
- Neurodevelopmental Disorders
Background:
- Delayed sleep-wake phase disorder (DSWPD) is a chronic condition affecting adolescents, impacting their quality of life.
- Distinguishing intrinsic versus behavioral factors in DSWPD is challenging in clinical settings.
- This study investigated DSWPD in adolescents, assessing comorbidities and diagnostic methods.
Purpose of the Study:
- To compare clinical interviews, sleep diaries, actigraphy, and polysomnography (PSG) in adolescents with DSWPD.
- To evaluate the prevalence of psychiatric and neurodevelopmental comorbidities in this cohort.
- To determine the utility of PSG in identifying sleep timing issues in DSWPD.
Main Methods:
- Thirty-one adolescents (mean age 15.4 years) diagnosed with DSWPD underwent PSG.
- Participants also received neurological, psychological, and psychiatric examinations.
- Data from history, sleep diaries, and actigraphy were compared with PSG findings.
Main Results:
- High rates of comorbidities were observed: ADHD (45%), learning difficulties (29%), and mood disorders (52%).
- Polysomnography confirmed delayed sleep onset in only 38% of diagnosed cases.
- Patients with delayed sleep onset showed reduced total sleep time, sleep efficiency, and altered REM sleep parameters.
Conclusions:
- Polysomnography confirmed delayed sleep timing in only 38% of adolescents diagnosed with DSWPD.
- PSG may help differentiate biological from behavioral causes of DSWPD when melatonin testing is unavailable.
- Psychiatric and neurodevelopmental comorbidities are highly prevalent in adolescents with DSWPD.
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