Do depression and anxiety profiles over time predict persistent post-surgical pain? A study in cardiac surgery patients.

BACKGROUND: Rates of depression and anxiety in cardiac surgery patients are higher than in the general population. The development of persistent post-surgical pain (PPSP) in this population is also concerning. The objectives of this study were to (1) identify anxiety and depression trajectories of cardiac surgery patients over a 2-year period; (2) examine demographic and clinical characteristics associated with trajectory memberships and (3) determine if anxiety and/or depression trajectories predict PPSP.

METHODS: A total of 1071 patients completed questionnaires before cardiac surgery and 7 days, 3, 6, 12 and 24 months thereafter. Models were run using growth mixture modelling.

RESULTS: Both anxiety and depression models yielded a 3-trajectory solution. A minority of patients (< 10%) had unremitted major depression, almost one-third of patients had remitted minor depression and the remaining patients had no depression over the 2-year period. < 10% of patients had unremitted elevated anxiety, almost 40% of patients had unremitted mild anxiety symptoms, whereas half of patients did not experience anxiety over the same time period. Patients with unremitted elevated anxiety were more likely to report PPSP; the association between depression and PPSP was not significant.

CONCLUSIONS: The results' novelty lies in the identification of a homogeneous patient subgroup presenting with unremitted elevated anxiety which predicted the presence of PPSP up to 2 years following cardiac surgery. Unlike anxiety, depression subgroups were not predictive of PPSP status.

SIGNIFICANCE: This article presents the relationship between anxiety and depression profiles over 2 years in cardiac surgery patients and persistent post-surgical pain. These results suggest the importance of evaluating how early identification and treatment of high-risk patients could prevent PPSP. These results provide potential detection and prevention avenues of chronic pain for high-risk patients based on their anxiety trajectory.