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.