Teaching NeuroImage: Non–24-Hour Sleep-Wake Rhythm Disorder
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A 77-year-old woman with obstructive sleep apnea reported a lifelong difficulty with periods of severe nocturnal insomnia and daytime sleepiness. Wrist actigraphy, the diagnostic method of choice for circadian rhythm disorders, was not covered by insurance. A review of her CPAP data (Figure) demonstrated progressively later bedtimes with a period of greater than 24 hours, revealing the diagnosis of non–24-hour sleep-wake rhythm disorder. While common in unsighted individuals, non–24-hour sleep-wake rhythm disorder can occur in sighted people,1,2 as was the case here. For patients on PAP therapy, adherence data can provide evidence of circadian rhythm disorders.
Each green bar represents 1 day of CPAP use with the top representing CPAP initiation, approximating sleep onset, and the bottom representing CPAP discontinuation, approximating end of sleep. The image produces a unique diagonal band appearance.
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The authors report no targeted funding.
Disclosure
The authors report no disclosures relevant to the manuscript. Go to Neurology.org/N for full disclosures.
Acknowledgment
The authors thank Onyinye Iweala, MD, PhD for reviewing the manuscript.
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Footnotes
Go to Neurology.org/N for full disclosures.
↵* These authors contributed equally to this work.
Submitted and externally peer reviewed. The handling editor was Roy Strowd III, MD, Med, MS.
Teaching slides links.lww.com/WNL/B906.
- Received November 29, 2021.
- Accepted in final form March 4, 2022.
- © 2022 American Academy of Neurology
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