Death after head injury: the 13 year outcome of a case control study
- 1Psychological Medicine, Faculty of Medicine, University of Glasgow, Glasgow, UK
- 2NHS Quality Improvement Scotland, Glasgow, UK
- 3MRC Hub for Trials Methodology Research, Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK
- Correspondence to Professor T M McMillan, Psychological Medicine, Faculty of Medicine, University of Glasgow, Gartnavel Royal Hospital, 1055 Great Western Road, Glasgow G12 0XH, UK;
Contributors TMMM was the primary investigator for the follow-up study and took a lead role in writing the manuscript. GMT was the primary investigator for the original prospective study and commented at all stages in the follow-up project. CJW provided statistical advice and analysed the data. ES was the research worker on the follow-up project and contributed to the manuscript.
- Received 25 June 2010
- Revised 3 November 2010
- Accepted 17 November 2010
- Published Online First 31 January 2011
Background Head injury is common, and the risk of subsequent disability and death is high. Increased risk of death years after injury might be explained by factors associated with, but not a consequence of, the head injury. This unique prospective study investigates mortality over 13 years after injury.
Methods A cohort of n=767 with head injury was compared with two case control groups, matched for age, gender and deprivation, and in one control group, matched for duration of hospital admission following (non-head) injury.
Results Two-fifths of the head injury cohort had died. The death rate (30.99 per 1000 per year) was much higher than in community controls (13.72 per 1000 per year). More than 1 year after injury, the death rate in younger (15–54 years) adults was much higher than in community controls (17.36 vs 2.36 per 1000 per year) whereas in older adults the difference was more marginal (61.47 vs 42.36). Death rate was elevated after mild and after more severe head injury, including in younger adults after mild head injury (14.82 per 1000 per year mild head injury vs 2.21 community). Female gender and greater deprivation were not associated with increased death rates after head injury. Late after injury, deaths occurred from the same main causes as for the general population.
Conclusion Head injury is associated with increased vulnerability to death from a variety of causes for at least 13 years after hospital admission. There is a need to understand how head injury influences mortality, particularly in younger adults and after mild head injury.
Funding The 13 year follow-up was funded by the Chief Scientist Office (CZG/2/397). The original prospective study was also funded by the Chief Scientist Office (K/OPR/2/2/D229).
Competing interests None.
Ethics approval This study was conducted with the approval of the NHS Greater Glasgow and Clyde Research Ethics Committee (08/S0710/82).
Provenance and peer review Not commissioned; externally peer reviewed.