The Association Between Pain Type, Cognition and Complaint After Mild Traumatic Brain Injury in Prospectively Studied Premorbidly Healthy Adults Admitted to Hospital

Objective: Literature examining the relationship between pain, cognition, and complaint after mild traumatic brain injury (mTBI) has conceptualized and measured pain as a unitary construct. Pain is defined as being multidimensional, however, with both sensory and affective aspects. The current study aimed to determine whether the sensory and affective aspects of pain differentially relate to cognition and complaint. Method: Using a prospective observational design, 6-10 weeks after injury, we assessed 60 premorbidly healthy individuals, who were admitted to hospital after an mTBI. Participants were assessed with multidimensional and unitary pain questionnaires, as well as measures of cognition, complaint, anxiety and depression. Results: Findings showed that a univariate measure of pain did not successfully measure affective pain. Multidimensional pain assessment revealed that affective descriptors of pain were significantly and independently associated with aspects of cognitive function (p <.05). A number of sensory types of pain also significantly related to cognition (p <.05), with these relationships varying between the different sensory pain types. Continuous type sensory pain also independently predicted memory and executive function. No independent linear relationships were evident between any type of pain and level of complaint. Conclusions: These findings show for the first time that it is important to examine both affective and sensory aspects of pain in individuals after mTBI, as pain subtypes show differential relationships with cognition. The study also suggests that the relationship between pain and complaint is not an independent one. This study has implications for treatment and management of individuals experiencing cognitive difficulties after mTBI.