Smoking and insomnia go hand in hand, study shows

Smokers who have difficulty falling asleep at night may find it doubly hard to stop smoking, a study suggests. At the same time, non-insomniac smokers may develop symptoms of sleeplessness if they continue using tobacco.

The study included 2,568 adults (mean age, 40.1 years; 53.3 percent female; mean body mass index, 24.5 kg/m²) who smoked at baseline. They had completed a questionnaire in 1999–2001 (RHINE II) and a follow-up one in 2010–2012 (RHINE III).

Smokers vs never smokers at baseline were older and more frequently have diabetes, chronic bronchitis, snoring, sleep disturbances, and daytime sleepiness. In the entire population, 23 percent reported insomnia symptoms (defined as having difficulty initiating and/or maintaining sleep and/or early morning awakening ≥3 nights/week).

Multiple logistic regression analyses revealed that insomnia and excessive daytime sleepiness were negative predictors of smoking cessation. Specifically, long-term smoking cessation was less likely to be achieved by smokers with trouble initiating sleep (adjusted odds ratio [aOR], 0.6, 95 percent confidence interval [CI], 0.4–0.8), difficulty maintaining sleep (aOR, 0.7, 95 percent CI, 0.5–0.9), early morning awakening (aOR, 0.6, 95 percent CI, 0.4–0.8), any insomnia symptom (aOR, 0.6, 95 percent CI, 0.5–0.8), or excessive daytime sleepiness (aOR, 0.7, 95 percent CI, 0.5–0.8).

There was no significant association between snoring and smoking cessation.

Among participants without sleep disturbance at baseline, continued smoking was associated with a higher likelihood of developing a difficulty initiating sleep during the follow-up period compared with those who had quit smoking (aOR, 1.7, 95 percent CI, 1.2–2.3).