The relationship between pain, anxiety and depression in patients with post-intensive care syndrome.

Purpose: Survivors of critical illness frequently experience long-term symptoms including physical symptoms such as pain and emotional symptoms such as anxiety and depression. These symptoms frequently co-exist, however, at present there is limited understanding of these relationships. The aim of this study was to quantify the relationship between pain, anxiety and depression across the recovery trajectory.

Methods: This study is a secondary analysis of data from a multi-centre, prospective, cohort study which followed-up patients recovering from critical illness. Data was available at multiple time points and for 3 distinct cohorts. Structural equation modelling was used to investigate the relationship between outcome measures of pain, anxiety and depression.

Results: Data from 414 patients was analysed. Pain was significantly associated with both anxiety and depression in all cohorts and at all time points sampled. Path coefficients for the covariances between pain and depression ranged between 0.39 and 0.72 (p < 0.01). Path coefficients for the covariances between pain and anxiety ranged between 0.39 and 0.65 (p < 0.01).

Conclusions: Pain, anxiety and depression are highly correlated in survivors of critical illness. Pharmacological treatments for pain management may be ineffective alone and further research is required to assess interventions targeting these symptoms in combination.