Abnormal night sleep duration and inappropriate sleep initiation time are associated with elevated anxiety symptoms in Chinese rural adults: the Henan Rural Cohort

Sleep problems have been demonstrated to cause mental symptoms, such as anxiety. However, research on the association of the night sleep duration and sleep initiation time on anxiety symptoms in rural China is still lacking. The current study, therefore, explored the independent and combined association of the night sleep duration and sleep initiation time on anxiety symptoms. This study included 28, 054 participants from the Henan Rural Cohort. Sleep was measured using the Pittsburgh Sleep Quality Index (PSQI). Anxiety was assessed by the two-item Generalized Anxiety Disorder scale (GAD-2). Multivariable logistic regression models and restricted cubic spline with anxiety symptoms as a dependent variable were fitted. Among the participants in this study, 11, 209 (39.96%) were males, and 16,845 (60.04%) were females, 1574 (5.61%) had anxiety symptoms. Both shorter and longer night sleep duration were significantly related to elevated prevalence of anxiety symptoms. Extreme sleep initiation time was also significantly associated with elevated anxiety symptoms. Additionally, night sleep duration and sleep initiation time had a combined effect on the prevalent anxiety symptoms. In conclusion, there was a dose-response association of night sleep duration and sleep initiation time with anxiety among Chinese rural population. Moreover, they might jointly increase the odds of prevalent anxiety.