The bidirectional relationship between sleep disturbance and anxiety: Sleep disturbance is a stronger predictor of anxiety

Background: Both sleep disturbance and anxiety are common problems that significantly affect human health, but little is known about their causal relationship. The aim of this study was to explore the causal relationship between them with a large sample of community-dwelling adults included. Methods: Data for this study were extracted from the baseline survey of West China Natural Population Cohort Study (WCNPCS) and follow-up in the following year. The sleep quality was assessed using Pittsburgh Sleep Quality Index (PSQI), and anxiety was screened using the Generalized Anxiety Disorder Scale (GAD-7). Age, gender, educational level, marital status, smoking status, drinking status, depressive symptoms, loneliness and chronic diseases were taken as covariant factors. Logistic regression and cross-lagged models were used for data analyses. Results: A total of 16699 participants (67.5 % females) were enrolled, with the average age of participants being 57.3 +/- 12.7 years. A total of 40.50 % of participants experienced poor sleep quality at baseline and 40.52 % at follow-up. The prevalence of anxiety was 7.58 % at baseline and 4.62 % at follow-up. The results showed that the risk of developing anxiety in individuals with sleep disturbance at baseline was 1.89 times higher than those without (95%CI = 1.43-2.48). Similarly, anxiety increased the risk of developing sleep disturbance by 1.20-fold (95%CI = 1.03-1.39). These results were further supported by the cross-lagged panel models. Conclusion: Sleep disturbance and anxiety are mutually causal, and the effect of poor sleep on anxiety seems to be more significant. Timely interventions targeting sleep may help to break the vicious circle between sleep disturbance and anxiety symptoms, and improve the quality of life.