The relation between smoking and sleep: the influence of smoking level, health, and psychological variables.

The relation between smoking and sleep was examined in a randomly selected sample of 769 individuals (379 men and 390 women, ages 20 to 98). Participants completed 2 weeks of sleep diaries, provided a global report on their sleep, indicated the number of cigarettes smoked per day, and supplied information on health, depressive symptoms, anxiety, and caffeine and alcohol use. After controlling for demographic, health, psychological, and behavioral variables, light smoking (< 15 cigarettes per day), but not heavier smoking, was associated with self-reported chronic insomnia and reduced sleep diary total sleep time and time in bed. Smokers did not differ significantly from nonsmokers on diary measures of sleep-onset latency, number of awakenings during the night, wake time after sleep onset, or sleep efficiency.