Plasma brain-derived neurotrophic factor levels after severe traumatic brain injury

Abstract

Objective: Severe traumatic brain injury (TBI) is associated with a 30–70% mortality rate. Nevertheless, in clinical practice there are no effective biomarkers for the prediction of fatal outcome following severe TBI. Therefore, the aim was to determine whether brain-derived neurotrophic factor (BDNF) plasma levels are associated with intensive care unit (ICU) mortality in patients with severe TBI.

Methods: This prospective study enrolled 120 male patients who suffered severe TBI (Glasgow Coma Scale 3–8 at emergency room admission). The plasma BDNF level was determined at ICU admission (mean 6.4 hours after emergency room admission).

Results: Severe TBI was associated with a 35% mortality rate and 64% of the patients presented severe TBI with multi-trauma. The mean plasma BDNF concentration among the severe TBI victims was 704.2 ± 63.4 pg ml⁻¹ (±SEM). Nevertheless, there were no significant differences between BDNF levels in the survivor (700.2 ± 82.8 pg ml⁻¹) or non-survivor (711.6 ± 97.4 pg ml⁻¹) groups (p = 0.238) or in the isolated TBI (800.4 ± 117.4 pg ml⁻¹) or TBI with multi-trauma groups (650.5 ± 73.9 pg ml⁻¹) (p = 0.109).

Conclusions: Plasma BDNF concentrations did not correlate with either short-term fatal outcome or type of injury following severe TBI.

• BDNF
• biomarker
• multi-trauma
• outcome
• severe TBI

Declaration of interest

The present study received financial support from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; research grant 568691/2008-3) and from Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS; research grant 09/0041-5, 1630-25.51/09-0).

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.