Abstract
OBJECTIVE: Sleep is vital for homeostasis. Smoking negatively affects sleep quality, whereas regular physical activity and reduced sedentary behavior improve sleep quality. However, the combined effect of e-cigarettes, physical activity, and sedentary behavior remains unknown. Therefore, the current study compared sleep quality according to e-cigarette dependence status among adults with high versus low levels of physical activity and sedentary behavior. METHODS: In 644 adults, sleep, e-cigarette dependence, physical activity, and sedentary behavior were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Penn State E-Cigarette Dependence Index, and the International Physical Activity Questionnaire, respectively. RESULTS: The two-way ANCOVA, after controlling for gender, income, and disease status, revealed main effects of e-cigarette dependence (p<0.001) and sedentary behavior (p<0.03), and an interaction effect (p<0.05) on the PSQI. Post hoc comparisons showed significantly greater PSQI scores among adults with heavy e-cigarette dependence and in the high sedentary behavior group (p<0.05). However, the analysis showed no main effect of physical activity on PSQI scores (p>0.05). CONCLUSIONS: The results suggest that heavy dependence on e-cigarettes negatively alters sleep quality. These adverse sleep alterations are exacerbated by sedentary behavior. Programs are needed to reduce e-cigarette use and sedentary behavior to enhance sleep quality.