Severe traumatic brain injury in a large Canadian health region

Although severe traumatic brain injury (sTBI) is a devastating condition with tremendous public health implications, the epidemiology of this disease has not previously been described in Canada. We sought to define the incidence, risk factors and outcome of patients suffering sTBI in a large Canadian region.

A population-based surveillance cohort design was utilized to identify all Calgary Heath Region residents who were victims of trauma with an injury severity score > or = 12. Subsequent application of a specific sTBI case definition defined the final cohort.

The annual incidence of sTBI was 11.4 per 100,000 population. The incidence of sTBI was significantly higher for males as compared to females [17.1 vs. 5.9 per 100,000; relative risk (RR) = 2.91, 95% confidence interval; 2.17, 3.94; p<0.0001]. There was a striking increase in the annual age specific population incidence of sTBI observed among those older than 74 years of age. The relative risk among the highest risk group of elderly (>85 years) males as compared to the lowest risk female group (50-64 years) was 19.78 (95% CI; 6.27, 62.3; p<0.0001). One hundred and eight patients died prior to hospital discharge for a mortality rate of 5.1 per 100,000 per year.

Severe traumatic brain injury is common among residents of the Calgary Health Region and is associated with a high mortality rate. Males and the elderly are at the highest risk for acquiring sTBI and may represent target groups for preventive efforts.