Mortality among older adults after a traumatic brain injury: A meta-analysis

Primary objective: To examine mortality rates among older adults (>= 60 years) post-traumatic brain injury (TBI). Research design: Systematic review and meta-analysis. Methods and procedures: Using multiple databases, a literature search was conducted for articles on mortality after TBI published up to July 2011. Information on patient characteristics (age, Glasgow Coma Scale (GCS), injury aetiology, etc.), mortality rates, time to death and study design was extracted and pooled. Main outcomes and results: Twenty-four studies had an overall mortality rate of 38.3% (CI 27.1-50.9%). The odds of mortality for those over 75 years compared to those of 65-74 years was 1.734 (CI=1.311-2.292; p<0.0001). Pooled mortality rates for mild (GCS 13-15), moderate (GCS 9-12) and severe (GCS 3-8) head injuries were 12.3% (CI=6.1-23.3%), 34.3% (CI=19.5-53.0%) and 65.3% (CI=53.1-75.9), respectively. Odds ratios comparing severe to mild and moderate to mild head injuries were 12.69 (CI=5.29-30.45; p<0.0001) and 5.31 (CI=3.41-8.29; p<0.0001), respectively. There was no significant difference in the odds of death between severe and moderate injuries (p=0.116). Conclusions: These mortality rates associated with moderate and severe injuries may be attributed to complications, chronic disease prevalence, conservative management techniques or the consequences of biological ageing.