The Mediating Role of Pain Catastrophizing: Understanding the Relationship Between Psychological Distress and Functional Disability in Mild Traumatic Brain Injury

Abstract

Background. Recovery following brain injury can be significantly impeded by the way in which an individual appraises pain, which in turn, can affect ability to cope with pain, and result in psychological distress. Pain catastrophizing, implicated in the appraisal of pain, can exacerbate the intensity of pain-related distress and impact psychological well-being. However, the concurrent evaluation of these phenomena via functional outcomes has not been examined in mild traumatic brain injury. Material and methods. The present study evaluated de-identified archival data of 190 patients with mild traumatic brain injury following injury in motor vehicle accidents. Of primary interest was whether pain catastrophizing mediated the relationship among psychological distress (i.e., anxiety, depression) and functional disability outcomes in patients with mild traumatic brain injury. Results. Pain catastrophizing was found to have a significant mediating effect on the relationship between anxiety and functional disability, as well as for depression and functional disability. Age, gender, time since injury, and/or pain intensity, were not significant predictors of outcome. Although, pain severity was linked to pain catastrophizing. Moreover, the current work also evaluated feigning amongst a subset of patients with mild traumatic brain injury. Interestingly, it appears that the presence of psychological distress, irrespective of the nature of that reporting, is itself predictive of functional well-being. This is an important clinical finding and supports the role of psychological factors on real-life functional compromise in patients with mild traumatic brain injury. Conclusion. The present study found that psychological distress and functional disability are mediated by pain catastrophizing in patients with mild traumatic brain injury. It also appears that the presence of psychological distress, irrespective of the level of reported complaints (i.e., the over-reporting of symptomatology) itself, is predictive of functional well-being.