Illness Perceptions in Complex Regional Pain Syndrome

Abstract

Background: Complex Regional Pain Syndrome (CRPS) is a chronic pain condition that is accompanied by sensory, vasomotor, trophic and motor symptoms. Several multifaceted physiological systems underpin this condition, some of which are likely influenced by psychological factors. Research has shown mixed findings regarding the importance of psychological factors in CRPS, however, in other pain conditions pain-specific psychological variables are influential. Illness perceptions are one psychological variable that is associated with pain outcomes and emotional distress in other pain conditions and could be important in CRPS. Aim: To investigate CRPS patients' illness perceptions in relation to pain outcomes and, to see whether patient drawings are a useful tool to assess these perceptions. Method: 53 participants who met the Budapest Diagnostic Criteria of CRPS completed questionnaires on: illness perceptions, pain, disability, depression, anxiety, stress, pain-catastrophizing and kinesiophobia, a drawing task and answered three open-ended questions on their perceptions of CRPS. Results: Negative illness perceptions were found to be associated with pain related outcomes. Higher illness identity perceptions (attributing more symptoms to CRPS) and higher negative affect were associated with higher pain intensity. Lower illness coherence perceptions (poorer understanding), higher pain and being on ACC income compensation were associated with higher disability. No illness perceptions were associated with depression, however, higher catastrophising and higher negative affect were associated with higher depression. Lower illness coherence perceptions and higher catastrophising were associated with higher kinesiophobia. Drawings were not found to be an effective tool to measure CRPS patients' illness perceptions. Answers to open-ended questions demonstrated a range of understanding of CRPS amongst patients; with many patients' reporting a poor understanding. Patients' reported a number of severe consequences of the condition and attributed different causes to their CRPS. Conclusion: CRPS patients who lack a good understanding of their condition may engage in catastrophising and experience increased pain, disability and kinesiophobia. Future experimental research is required to investigate the relationship between CRPS patients' understanding and pain outcomes. However, these findings show that patients' perceptions are important in CRPS as they influence pain and emotional outcomes.