Abstract
Background: Coronary artery disease (CAD), a leading cause of morbidity and mortality worldwide, negatively impacts psychological well-being. Depressive and anxiety symptoms are commonly reported by patients with CAD, but little is known about symptom interconnectedness in this population. Insight into this interconnectedness may improve our understanding of how comorbidity arises and persists. Therefore, our aim was to gain new insights into the comorbidity of anxiety and depression symptoms in patients with CAD by estimating psychological networks at multiple time points. Methods: 2241 patients who had undergone percutaneous coronary intervention (22.2% women; mean age = 65.0, SD= 10.3) were included. With five cross-sectional psychological networks measured at five timepoints over two years, the symptom-level dynamics of depressive and anxiety symptoms were studied. Besides the overall network structure, network communities, centrality measures and sub-group differences were explored. Results: The estimated Bayesian Gaussian graphical models showed predominantly positive associations, and symptoms were mostly connected within their own domain of depression or anxiety. Two symptom clusters remained relatively stable: Depressed mood, feelings of worthlessness, and suicidal ideation consistently clustered together, while in the first month post PCI, fatigue, sleep disturbance, and appetite disturbance tended to co-occur. Fatigue, depressed mood, difficulty relaxing, and restlessness showed high connectivity and acted as bridging symptoms between different symptom groups. Conclusion: These findings suggest that both symptoms related to depression and to anxiety should be targeted within cardiac rehabilitation programs to reduce patients' psychological burden.