Study Finds Evening Use of Nicotine and Alcohol Associated With Sleep Disturbances
Sleep efficiency is the percentage of time spent asleep while in bed. A normal sleep efficiency is considered to be 85% or higher. Wake after sleep onset refers to how much time a person spends awake after initially falling asleep. A new study looked at the association between evening use of alcohol, caffeine, and nicotine and sleep and found that nicotine and alcohol use within 4 hours of bedtime are associated with decreased sleep efficiency and increased wake after sleep onset.
Participants in the study included 785 adults with an average age
of 63.7 who took part in the Jackson Heart Sleep Study. Participants wore a wrist-watch-like
sensor for an average of 6.7 nights to record sleep activity. They also kept
daily sleep diary assessments to record consumption of alcohol, caffeine, and
nicotine within 4 hours of bedtime.
Alcohol use in the evening was associated with lower sleep
efficiency, but not with sleep duration or wake after sleep onset. Nicotine use
in the evening was associated with lower sleep efficiency and 6.09 higher
minutes of wake after sleep onset. In insomniacs, evening nicotine use was
associated with an average 42.47-minute reduction in sleep duration. Caffeine
use in the evening was not associated with any of the sleep parameters.
The study was conducted by researchers from Florida Atlantic
University, Brigham and Women’s Hospital, and Harvard Medical School. It was published
online ahead of print on August 6, 2019 in the journal Sleep.