Cause of Death after Traumatic Brain Injury: A Population-Based Health Record Review Analysis Referenced for Nonhead Trauma

Abstract

<b><i>Introduction:</i></b> Traumatic brain injury (TBI) is a leading cause of disability and is associated with decreased survival. Although it is generally accepted that TBI increases risk of death in acute and postacute periods after injury, causes of premature death after TBI in the long term are less clear. <b><i>Methods:</i></b> A cohort sample of Olmsted County, Minnesota, residents with confirmed TBI from January 1987 through December 1999 was identified. Each case was assigned an age- and sex-matched non-TBI referent case, called <i>regular referent</i>. Confirmed TBI cases with simultaneous nonhead injuries were identified, labeled <i>special cases</i>. These were assigned 2 age- and sex-matched <i>special referents</i> with nonhead injuries of similar severity. Underlying causes of death in each case were categorized using death certificates, <i>International Classification of Diseases</i>, <i>Ninth Revision</i>, <i>International Statistical Classification of Diseases</i>, <i>Tenth Revision</i>, and manual health record review. Comparisons were made over the study period and among 6-month survivors. <b><i>Results:</i></b> Case-regular referent pairs (<i>n</i> = 1,257) were identified over the study period, and 221 were special cases. In total, 237 deaths occurred among these pairs. A statistically significant difference was observed between total number of deaths among all cases (<i>n</i> = 139, 11%) and regular referents (<i>n</i> = 98, 8%) (<i>p</i> = 0.006) over the entire period. This outcome was not true for special cases (32/221, 14%) and special referents (61/441, 14%) (<i>p</i> = 0.81). A greater proportion of deaths by external cause than all other causes was observed in all cases (52/139, 37%) versus regular referents (3/98, 3%) and in special cases (13/32, 41%) versus special referents (5/61, 8%) (<i>p</i> < 0.001 for both). Among all case-referent pairs surviving 6 months, no difference was found between total number of deaths (<i>p</i> = 0.82). The underlying cause of death between these 2 groups was significantly different for external causes only (<i>p</i> < 0.01). For special cases surviving 6 months versus special referents, no difference was observed in total number of deaths (<i>p</i> = 0.24) or underlying causes of death (<i>p</i> = 1.00) between groups. <b><i>Discussion/Conclusion:</i></b> This population-based case-matched referent study showed that increased risk of death after TBI existed only during the first 6 months after injury, and the difference was due to external causes.

Long-Term Risk for Mood and Anxiety Disorders After Pediatric Traumatic Brain Injury: A Population-Based, Birth Cohort Analysis

“…This process had the potential to result in inaccurate classification of mood or anxiety disorders and did not account for changes in diagnostic practices over time; however, the same approach was used for all persons with the abstractor blinded to case/referent status, and interrater reliability was determined to be adequate. Consistent with prior studies within our population-based sample, the incidence of TBI in this study was dominated by Possible/Probable TBI 35,44. The few Definite TBI cases limited the power to assess the significance of moderate to severe TBI as well as the development of long-term mood and anxiety disorders.…”

“…Consistent with prior studies within our population-based sample, the incidence of TBI in this study was dominated by Possible/Probable TBI. 35,44 The few Definite TBI cases limited the power to assess the significance of moderate to severe TBI as well as the development of long-term mood and anxiety disorders. In other studies, severe TBI has more consistently predicted poor long-term psychiatric and neurobehavioral outcomes.…”