The Complex Interplay of Pain, Depression, and Anxiety Symptoms in Patients with Chronic Pain: A Network Approach.

Objective: This study aimed to analyze the associations among depressive and anxiety and pain symptoms in patients diagnosed with chronic pain. Materials and Methods: Four hundred fifty-four inpatients who were consecutively admitted in a multimodal 3-week treatment in a tertiary, psychosomatic university clinic completed 25 items from the Brief Pain Inventory and the Hospital Anxiety and Depression Scale at baseline and after treatment termination. Associations among symptoms were explored by network analyses using the graphical least absolute shrinkage and selection operator to estimate their partial correlations, whereas Extended Bayesian Information Criterion was used to select the best network solution for the data. We explored symptoms' centrality and expected influence within the network and the minimum spanning tree for the network. Results: Besides expected associations within depressive and anxiety and pain symptoms, the estimated network showed several local associations between depressive and pain interference symptoms. The lacks of being cheerful and of laughing are 2 of the depressive symptoms that showed the greatest associations with pain interference and a strong centrality within the network. Sleep problems were associated with both anxiety and depressive symptoms and pain intensity symptoms. Although at posttreatment most of the symptoms showed a significant decrease, the strength of the associations between the symptoms within the network was significantly higher than at baseline. Discussion: The results support focusing psychosocial interventions in chronic pain treatment not only on reducing pain, anxiety, and sleep symptoms but also on enhancing positive affect. Future research is needed to replicate these findings using repeated within-person measures designs.