Daily patterns of melatonin and body clock gene activity in unexplained REM sleep behavior disorder

RBD patients exhibited a 2-hour delay in melatonin secretion compared to healthy controls.

• Circadian rhythmicity was absent for the clock genes Per2, Bmal1, and Nr1d1 in RBD patients.
• The rhythmicity of the clock gene Per1 remained in RBD patients, while the amplitude of Per3 was reduced.
• The melatonin profile of RBD patients showed a more dispersed range of acrophases over 11 hours compared to the stable 5-hour range in controls.
• Habitual sleep phases in RBD patients were phase delayed by about 1 hour.
• No phase shift was observed in any of the clock genes studied in RBD patients.

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