Co-morbidities in trauma patients: common and significant

Trauma is a heterogeneous 'disease' that affects all age groups with varying degrees of severity. While injury severity, time to definitive care, and the quality of care in trauma patients have been quantified, it has been much more difficult to quantify pre-existing health status or 'host factors' in trauma patients and relate them to trauma outcome. Numerous studies have attempted this task, but none have succeeded in producing a simple system to quantify co-morbidities. As a prelude to developing a simple Abbreviated injury scale (AIS)-like score, the incidence of major and minor co-morbidities (and outcomes) in a cohort of admitted trauma patients > or =40 years of age were evaluated.

A prospective review of the Auckland Trauma Registry of trauma patients age > or =40 years that were admitted to Auckland Hospital between 1 January 2003 and 3 March 2003 was performed. Among the data collected were the patient's co-morbidities. The co-morbidities were divided into major and minor co-morbidities: major co-morbidities were defined by criteria found in the APACHE 2 PIC system, whereas minor co-morbidities were all the other co-morbidities not included in the APACHE 2 PIC system.

A total of 105 patients were included. There were 57 males and 48 females in this study. Overall, 71% of the population had pre-existing co-morbid conditions, with 23% having a major co-morbid condition. Major trauma [injury severity score (ISS) of 15] was seen to decrease as age increases. The mortality rate in this group of patients was 4.7%.

Co-morbidities were surprisingly common in trauma patients. Trauma outcome in patients with co-morbidities is difficult to predict and is not well addressed by any of the existing injury scales. The possibility of developing single 'AIS-like' co-morbidity score merits ongoing evaluation. The prevalence of co-morbidities in trauma patients > or =40 years of age suggests that the influence of co-morbidity on outcome should be considered in a much greater cohort than is currently the case.