A systematic review of fatigue in patients with traumatic brain injury: The course, predictors and consequences

BACKGROUND Fatigue is common after traumatic brain injury (TBI). Its risk factors, natural history and consequences are uncertain. Best-evidence synthesis was used to address the gaps. METHODS Five databases were searched for relevant peer-reviewed studies. Of the 33 articles appraised, 22 longitudinal studies were selected. Results were reported separately based on their timing of baseline assessment. RESULTS All studies document changes in fatigue frequency and severity with time, irrespective of setting or TBI severity. There is limited evidence for certain clinical and psychosocial variables as predictors of fatigue severity at follow-up. Early fatigue severity predicted persistent post-concussive symptoms and Glasgow outcome score at follow-up. CONCLUSIONS Fatigue is present before and immediately following injury, and can persist long term. The variation in findings supports the idea of fatigue in TBI as a nonhomogeneous entity, with different factors influencing the course of new onset or chronic fatigue. To decrease the heterogeneity, we emphasize the need for agreement on a core set of relevant fatigue predictors, definitions and outcome criteria. PROSPERO registry number: CRD42013004262.