WASO (Wake after sleep onset)
DEWASO (Wachzeit nach dem Einschlafen)
Wake After Sleep Onset (WASO) is the total time you spend awake during the night. It counts the minutes after you first fall asleep, but before your final wake-up. It sums up all your wake spells in between. WASO is a core metric in sleep studies (polysomnography) and in actigraphy, standardized by the American Academy of Sleep Medicine. It feeds into your sleep efficiency. Sleep efficiency = total sleep time / time in bed. And total sleep time = time in bed, minus how long you took to fall asleep, minus WASO. A WASO above roughly 30 minutes is generally considered clinically significant. It is a diagnostic feature of insomnia disorder. WASO rises steadily with age, reflecting more frequent and longer awakenings. And it is raised in obstructive sleep apnea, restless legs syndrome, depression, menopause-related sleep complaints, and shift-work disorder.
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Sources
- Berry RB, Quan SF, Abreu AR, et al.. (2023). The AASM Manual for the Scoring of Sleep and Associated Events, Version 3. *American Academy of Sleep Medicine*
- Ohayon MM, Carskadon MA, Guilleminault C, Vitiello MV. (2004). Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: developing normative sleep values across the human lifespan. *Sleep*doi:10.1093/sleep/27.7.1255
- Riemann D, Espie CA, Altena E, et al.. (2023). The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023. *Journal of Sleep Research*doi:10.1111/jsr.14035