Prognostic utility of early plasma matrix metalloproteinases -2 and -9 concentrations after severe traumatic brain injury

Objective

To determine whether the matrix metalloproteinases-2 and -9 plasma levels were associated with intensive care unit mortality in patients who suffered severe traumatic brain injury, despite the presence of extracerebral injuries.

Methods

This prospective cohort enrolled 39 male patients who suffered severe traumatic brain injury (Glasgow coma scale: 3 - 8 at hospital admission). The plasma matrix metalloproteinase -2 and matix metalloproteinase -9 levels were determined by ELISA at the time of intensive care unit admission.

Results

Severe traumatic brain injury was associated with a 46% intensive care unit mortality rate. Higher plasma matrix metalloproteinase -9 concentrations were associated with mortality: 147.94 ± 18.00ng/mL for survivors and 224.23 ± 23.86ng/mL for nonsurvivors (mean ± standard error of the mean, p = 0.022). In contrast, there was no significant association between matrix metalloproteinase -2 levels and intensive care unit mortality: 315.68 ± 22.90ng/mL for survivors and 336.55 ± 24.29ng/mL for nonsurvivors (p = 0.499). Additionally, there were no significant associations between matrix metalloproteinase -2 (p = 0.711) and matrix metalloproteinase -9 (p = 0.092) levels and the presence of associated lesions.

Conclusion

Increased plasma matrix metalloproteinase -9 levels were associated with intensive care unit mortality following severe traumatic brain injury, regardless of the presence of extracerebral injuries. Conversely, in this same context, plasma matrix metalloproteinase -2 levels were not associated with short-term fatal outcome prediction.