Effect of Comorbid Illness on the Long-term Outcome of Adults Suffering Major Traumatic Injury: a Population-based Cohort Study

Background: Few studies have assessed the impact of pre-existing medical comorbidities on long-term survival after major trauma. This study investigated the influence of comorbidities as measured by the Charlson Comorbidity Index (CCI) on the 1-year mortality after major traumatic injury.

Methods: Adult patients who survived their initial trauma admission in Calgary, Alberta, Canada, between April 1, 2002, and March 31, 2006, defined the study population. Clinical and outcome information was obtained from regional electronic databases.

Results: The study population consisted of 3,080 patients. The median age was 43.3 years (interquartile range, 26.9-59.3 y), and the median Injury Severity Score was 20 (interquartile range, 16-25). A total of 478 patients (15.5%) had at least one pre-existing comorbidity. The 1-year mortality rate was 2.7% (83 of 3,080). After adjusting for the confounding effects of age, the CCI was independently associated with 1-year mortality with an odds ratio of 1.24 (95% confidence interval, 1.02-1.51; P = .03) per point on the CCI. A model that included the CCI and age accurately predicted 1-year mortality (C-statistic, .83; 95% confidence interval, .78-.87; P < .0001).

Conclusions: Comorbid illnesses have an important influence on long-term outcomes after major trauma. Whether this represents an inherent risk for adverse outcome or an opportunity for enhanced medical co-management remains to be defined.