Article

Traumatic brain injury (TBI) often leads to mood and cognitive
complications, affecting functional recovery. Understanding neurobiological
alterations common in post-TBI depression (PTD) and cognition may identify novel
biomarkers for TBI complications. Brain-derived neurotrophic factor (BDNF) is a
likely target based on evidence of reduced BDNF signaling in experimental TBI and
depression models and its role in learning and memory.
Objective: To evaluate BDNF
as a biomarker for PTD, cognitive impairment, and functional cognition in a
prospective cohort with severe TBI. Methods Participants with TBI (n = 113) were
evaluated for PTD (Patient Health Questionnaire-9 [PHQ-9]), cognitive impairment
(cognitive composite score), and functional cognition (Functional Independence
Measure-Cognition, FIM-Cog). BDNF levels were measured in cerebrospinal fluid and
serum at 0 to 6 days postinjury and in serum at 6 and 12 months postinjury.
RESULTS: Serum BDNF was reduced after TBI versus controls at all time points.
Acute serum BDNF positively correlated with memory composites (6 months: r =
0.43, P = .019, n = 30; 12 months: r = 0.53, P = .005, n = 26) and FIM-Memory
scores (6 months: r = 0.35, P = .019, n = 45; 12 months: r = 0.38, P = .018, n =
38). Acute serum BDNF negatively correlated with 12-month PHQ-9 scores (r =
-0.38; P = .044; n = 29). At 12 months, chronic serum BDNF tended to be lower in
participants with PTD (P = .07) and correlated with PHQ-9 scores (r = -0.41; P = .019; n = 32). Conclusions: Acute BDNF associations with memory recovery may
implicate hippocampal damage/degeneration. Comparatively, BDNF associations with
PTD status were not as strong as associations with PTD severity. Further
investigation may delineate longitudinal BDNF patterns, and BDNF responsive
treatments, reflecting mood and cognitive recovery following TBI.
CI - (c) The Author(s) 2015.

Langue : ANGLAIS