Mild traumatic brain injury: A prospective repeated measures study investigating the influence of illness perceptions and coping on clinical outcome.

Abstract

Background: Mild traumatic brain injury (MTBI) results in persisting disability for a significant minority and factors influencing non-recovery remain poorly understood. Descriptive recovery models suggest psychological factors become increasingly important with time but these models lack empirical support. Research in other health conditions suggests patient perceptions of symptoms and recovery can have powerful explanatory utility but such constructs have not been systematically explored in MTBI. Accordingly, a theoretically derived model of health behaviour such as Leventhal’s common sense model (CSM) could refine understandings about MTBI recovery. The objective of this research is to examine associations between components of the CSM (injury perceptions, distress, coping) and outcome after MTBI. The key clinical applications of this research are the earlier identification of both those at risk for atypical recovery and potential treatment targets, thus improving the effectiveness of MTBI interventions. Study Design: In a prospective observational cohort study with repeated measures, participants age 16 or older (n = 147) were recruited within three months following a MTBI and seen again six months later. Clinical and demographic information was collected and participants completed questionnaires at both visits (Revised Illness Perceptions Questionnaire (IPQ-R), Brief COPE, Hospital Anxiety and Depression Scale (HADS), Rivermead Post-Concussion Symptoms Questionnaire, Rivermead Head Injury Follow-Up Questionnaire). Associations between components of the CSM, and conservative MTBI outcome criteria were examined using univariate (Chi square, t-test) and multivariate (multiple regressions) statistical approaches. Results: Demographic and injury related variables were not associated with MTBI outcomes over time. However components of the CSM were significantly associated with outcomes. Participants endorsing unhelpful injury perceptions at time one, that is stronger beliefs about symptoms attributed to the injury (Odds Ratio (OR) 2.9, 95% Confidence Interval (CI) 1.2 to 6.7; p < 0.05), severity of expected consequences (OR 2.0, 95% CI 0.9 to 4.7; p = 0.09), chronicity of disability (OR 2.0, 95% CI 0.9 to 4.7, p = 0.09) and emotional impact (OR 3.4, 95% CI 1.4 to 8.0; p < 0.01), had significantly greater odds of poor outcome six months later. There were also significant associations between high distress at time one (HADS anxiety and depression scores) and poor outcomes over time. Associations between coping and outcome were inconsistent and problems with the way coping was conceptualised and measured may have contributed to variability in the results. Conclusions: Consistent with Leventhal’s CSM, those at baseline visit who attributed many symptoms to their MTBI, expected this to have severe and lasting consequences, and greater emotional impact, were more likely to have poor clinical outcomes six months later. Coping appeared to have important associations with outcome but the results were inconsistent. More research is required to examine whether coping mediates or influences outcomes more directly. A theoretically derived, coherent model of health behaviour such as Leventhal’s CSM, offers a reasoned approach to examining psychological factors with potential for both predicting those at risk for atypical MTBI recoveries, and development of clinical and research approaches to intervention.