Comorbidity in adults with traumatic brain injury and all-cause mortality: a systematic review

Abstract

ObjectivesComorbidity in traumatic brain injury (TBI) has been recognised to alter the clinical course of patients and influence short-term and long-term outcomes. We synthesised the evidence on the effects of different comorbid conditions on early and late mortality post-TBI in order to (1) examine the relationship between comorbid condition(s) and all-cause mortality in TBI and (2) determine the influence of sociodemographic and clinical characteristics of patients with a TBI at baseline on all-cause mortality.DesignSystematic review.Data sourcesMedline, Central, Embase, PsycINFO and bibliographies of identified articles were searched from May 1997 to January 2019.Eligibility criteria for selecting studiesIncluded studies met the following criteria: (1) focused on comorbidity as it related to our outcome of interest in adults (ie, ≥18 years of age) diagnosed with a TBI; (2) comorbidity was detected by any means excluding self-report; (3) reported the proportion of participants without comorbidity and (4) followed participants for any period of time.Data extraction and synthesisTwo independent reviewers extracted the data and assessed risk of bias using the Quality in Prognosis Studies tool. Data were synthesised through tabulation and qualitative description.ResultsA total of 27 cohort studies were included. Among the wide range of individual comorbid conditions studied, only low blood pressure was a consistent predictors of post-TBI mortality. Other consistent predictors were traditional sociodemographic risk factors. Higher comorbidity scale, scores and the number of comorbid conditions were not consistently associated with post-TBI mortality.ConclusionsGiven the high number of comorbid conditions that were examined by the single studies, research is required to further substantiate the evidence and address conflicting findings. Finally, an enhanced set of comorbidity measures that are suited for the TBI population will allow for better risk stratification to guide TBI management and treatment.PROSPERO registration numberCRD42017070033

Health Status Transitions Related to Traumatic Brain Injury.

“…Our results suggest that many disorders and social adversities preceding injury are reflected in external causes of injury and injury severity. Disorders clustering within the same external cause of injury and injury severity, as highlighted here, illuminate TBI as an event that is constructed within the context of health and social statuses, both formative and reflective 6,53 . For example, we observed that clusters composed of cardiovascular and metabolic disorders, stroke, dementia, and disorders of the elderly preceding TBI were strongly associated with falls and severe TBI.…”

Systems of Care and Natural History of Traumatic Brain Injury

“…18 TBI often causes irreversible pathological changes, persisting neurological defi cits, reduced life expectancy, and is associated with an increased risk of a variety of comorbidities, including seizures, endocrine dysfunction, sleep disorders, and psychiatric disorders. 19 TBI may be a risk factor for late neurodegenerative disorders, 20,21 and repetitive trauma can result in a variety of neuropathological fi ndings including a distinct, tau-related, neurodegenerative disorder, chronic traumatic encephalopathy. 22,23 Finally, TBI is a disorder with a wide variety of pathophysiological effects, a broad range of severities, and a multitude of problems that can occur as the result of injury.…”

Pre-injury health status and excess mortality in persons with traumatic brain injury: A decade-long historical cohort study

“…Although evidence exists for relationships between certain pre-existing comorbid disorders and both in-hospital and all-cause mortality 4,5 , uncertainty surrounds the magnitude of these associations, and the contributions of different comorbidities to the development of longterm adverse outcomes 6 . Chronic medical disorders, mental health disorders and alcohol and drug use, and a range of comorbid conditions through comorbidity indices are the most commonly reported predictors of all-cause mortality (supplementary table 1) [6][7][8][9][10][11][12][13][14][15] ; however, a variety of non-diagnostically specific ways were used to study and categorize these comorbidities and/or comorbidity indices 6 .…”

“…Although evidence exists for relationships between certain pre-existing comorbid disorders and both in-hospital and all-cause mortality 4,5 , uncertainty surrounds the magnitude of these associations, and the contributions of different comorbidities to the development of longterm adverse outcomes 6 . Chronic medical disorders, mental health disorders and alcohol and drug use, and a range of comorbid conditions through comorbidity indices are the most commonly reported predictors of all-cause mortality (supplementary table 1) [6][7][8][9][10][11][12][13][14][15] ; however, a variety of non-diagnostically specific ways were used to study and categorize these comorbidities and/or comorbidity indices 6 . By focusing almost exclusively on selective comorbid disorders within an individual, both mental and physical, that are collected via self-report measures or chart abstractions from clinical files 6 , clinicians and researchers may miss opportunities to risk-stratify patients with less common comorbidities, and those emerging from environmental adversities.…”

“…Chronic medical disorders, mental health disorders and alcohol and drug use, and a range of comorbid conditions through comorbidity indices are the most commonly reported predictors of all-cause mortality (supplementary table 1) [6][7][8][9][10][11][12][13][14][15] ; however, a variety of non-diagnostically specific ways were used to study and categorize these comorbidities and/or comorbidity indices 6 . By focusing almost exclusively on selective comorbid disorders within an individual, both mental and physical, that are collected via self-report measures or chart abstractions from clinical files 6 , clinicians and researchers may miss opportunities to risk-stratify patients with less common comorbidities, and those emerging from environmental adversities. Likewise, the burden of different comorbid disorders differs between male and female patients with TBI 7 , and it is possible that certain comorbidities may be more relevant and offer better predictive ability when studying mortality risk in the sexes, bringing forth another objective for the study of mortality in TBI -sex-specific analysis.…”