Abstract
PURPOSE: Depressive symptoms and sleep disorders were independent risk factors for cardiovascular diseases (CVD). However, few studies have examined the combined effects of depressive symptoms and sleep disorders on CVD. We aimed to evaluate the association between depressive symptoms, sleep disorders and CVD occurrence. METHODS: Data on 30,398 participants were extracted from the National Health and Nutritional Examination Survey (NHANES) database (2005-2018). Univariate and multivariate analyses were used for assessing the association of depressive symptoms, sleep disorders, and CVD occurrence. Three indexes, including the relative excess risk of interaction (RERI), attributable proportion of interaction (API), and synergy index (SI), were used to analyze the interaction. RESULTS: Of 30,398 participants, 11,544 (37.98%) participants had CVD and 18,854 (62.02%) did not. Except for gender, the differences were significant between CVD and non-CVD participants in all variables (all P<0.001). Depressive symptoms [odds ratio (OR)=1.73; 95% confidence intervals (CI):1.57-1.91] and sleep disorders (OR=1.76; 95% CI:1.65-1.88) were associated with an increased risk of CVD after adjusting all confounders. Patients with both depressive symptoms and sleep disorders (OR=2.64; 95% CI:2.32-3.00) had a higher risk of CVD than those without. There may be a synergistic interaction between depression and sleep disorders on the CVD occurrence (SI=1.763; 95% CI:1.299-2.394), and the proportion of CVD caused by this interaction was 26.9% (API=0.269; 95% CI:0.148-0.389). In addition, only moderate depressive symptoms may interact with sleep disorders in the occurrence of CVD. CONCLUSION: There may be a synergistic interaction between depressive symptoms and sleep disorders, and the synergistic interaction may increase the occurrence of CVD.