Sleep-Related Eating Disorder Emerges from NREM Sleep
Sleep-related eating disorder (SRED) is classified as a non-REM (NREM) parasomnia that occurs after arousals from the main sleep period, typically emerging from stages of NREM sleep rather than REM sleep. 1, 2
Sleep Stage Characteristics
- SRED episodes occur following arousals from NREM sleep, with patients experiencing partial or complete amnesia for the eating events 1
- The disorder manifests during transitions from night-time sleep to arousal, with varying levels of consciousness ranging from partial awareness to complete unawareness typical of somnambulistic episodes 3
- These episodes are characterized by compulsive consumption of food with impaired level of awareness and memory, distinguishing them from fully conscious eating behaviors 4
Clinical Context and Sleep Architecture
- SRED shares pathophysiological features with other NREM-related parasomnias, particularly sleepwalking, which also emerges from deeper stages of NREM sleep 1, 5
- The condition is associated with sleep fragmentation and other primary sleep disorders that disrupt normal NREM sleep architecture, including restless legs syndrome and obstructive sleep apnea 1
- Understanding that SRED arises from NREM sleep is clinically important because treatment of underlying sleep disorders that fragment NREM sleep (such as RLS or OSA) often improves SRED symptoms 1
Important Clinical Distinction
- SRED must be differentiated from night eating syndrome (NES), which occurs at full arousal from nocturnal sleep without accompanying amnesia and represents eating during complete wakefulness rather than a parasomnia 3, 5
- The level of consciousness during SRED episodes is a key distinguishing feature, with the semi-sleepiness state and subsequent amnesia indicating emergence from NREM sleep rather than full wakefulness 5