Transitioning from adequate to inadequate sleep duration associated with higher smoking rate and greater nicotine dependence in a population sample

Introduction Inadequate sleep (≤ 6 and ≥ 9 h) is more prevalent in smokers than non-smokers but the extent to which sleep duration in smokers relates to smoking behaviors and cessation outcomes, is not yet clear. To begin to address this knowledge gap, we investigated the extent to which sleep duration predicted smoking behaviors and quitting intention in a population sample. Methods Data from current smokers who completed the baseline (N = 635) and 5-year follow-up (N = 477) assessment in the United Kingdom Biobank cohort study were analyzed. Multivariable regression models using smoking behavior outcomes (cigarettes per day, time to first cigarette, difficulty not smoking for a day, quitting intention) and sleep duration (adequate (7–8 h) versus inadequate (≤ 6 and ≥ 9 h) as the predictor were generated. All models adjusted for age, sex, race, and education. Results Worsening sleep duration (adequate to inadequate) predicted a more than three-fold higher odds in increased cigarettes per day (OR = 3.18; 95% CI = 1.25–8.06), a more than three-fold increased odds of not smoking for the day remaining difficult (OR = 3.90; 95% CI = 1.27–12.01), and a > 8-fold increased odds of higher nicotine dependence (OR = 8.98; 95% CI = 2.81–28.66). Improving sleep duration (i.e., inadequate to adequate sleep) did not predict reduced cigarette consumption or nicotine dependence in this population sample. Conclusion Transitioning from adequate to inadequate sleep duration may be a risk factor for developing a more “hard-core” smoking profile. The extent to which achieving healthy sleep may promote, or optimize smoking cessation treatment response, warrants investigation.