Chronic impact of traumatic brain injury on outcome and quality of life: a narrative review

Abstract

Traditionally seen as a sudden, brutal event with short-term impairment, traumatic brain injury (TBI) may cause persistent, sometimes life-long, consequences. While mortality after TBI has been reduced, a high proportion of severe TBI survivors require prolonged rehabilitation and may suffer long-term physical, cognitive, and psychological disorders. Additionally, chronic consequences have been identified not only after severe TBI but also in a proportion of cases previously classified as moderate or mild. This burden affects the daily life of survivors and their families; it also has relevant social and economic costs.Outcome evaluation is difficult for several reasons: co-existing extra-cranial injuries (spinal cord damage, for instance) may affect independence and quality of life outside the pure TBI effects; scales may not capture subtle, but important, changes; co-operation from patients may be impossible in the most severe cases. Several instruments have been developed for capturing specific aspects, from generic health status to specific cognitive functions. Even simple instruments, however, have demonstrated variable inter-rater agreement.The possible links between structural traumatic brain damage and functional impairment have been explored both experimentally and in the clinical setting with advanced neuro-imaging techniques. We briefly report on some fundamental findings, which may also offer potential targets for future therapies.Better understanding of damage mechanisms and new approaches to neuroprotection-restoration may offer better outcomes for the millions of survivors of TBI.

Keywords: Axonal injury; Disability; Long-term outcome; Quality of life; Rehabilitation; Traumatic brain injury.

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Flow diagram of literature search

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Toxic and protective events in TBI over time

Fig. 3

Advanced diffusion imaging in a normal control subject (a–c) and a TBI patient (d–f). a, d Axial T2-weighted images at 0.7-mm isotropic resolution. b, e Fractional anisotropy and c, f mean diffusivity from diffusion tensor imaging. Cc corpus callosum, Cg cingulum, CR corona radiata, LV lateral ventricle. The color scheme indicates quantitative diffusion parameters (not direction of fibers). Processing included averaging of two acquisitions with opposite phase encoding direction acquisitions and eddy current correction plus motion correction using the Human Connectome Project pipeline which included FSL 5.0.6. (L. Holleran, JH Kim, and DL Brody, unpublished data)