RESUMO
Objective To determine the association between plasma concentrations of brain derived neurotrophic factor (BDNF), neuron-specific enolase (NSE), and S100β, and the occurrence of delirium in critically ill patients. Methods Totally 65 patients in Intensive Care Unit (ICU) of Wuxi People's Hospital of Nanjing Medical University between June 2015 and February 2016 were included in the present study. Delirium diagnosis was used by confusion assessment method for the ICU (CAM-ICU). Plasma BDNF, NSE, and S100β concentrations were determined on day 1(T1), 3(T3), and 10(T10) after ICU admission. The day of ICU admission was defined as T0. Results Compared with the plasma BDNF level on T1 (0.23±0.22) μg/L, the plasma BDNF level on T3 (0.59±0.34) μg/L and T10 (0.24±0.21) μg/L were higher, especially for that on T3 with a significant difference (F=21.58, P=0.018). Plasma NSE level on T3 (1.68±0.25) μg/L was significantly higher than that on T1 (1.22±0.32) μg/L (F=10.24, P=0.042). Compared with those without delirium, the delirious patients had lower BDNF, higher NSE and S100β on T1, T3 and T10, of which the difference of BDNF [T1: (0.23±0.22) μg/L vs. (1.02±0.24) μg/L, F=116.25,P<0.01; T3: (0.59±0.34) μg/L vs. (1.55±0.36) μg/L, F=82.39, P<0.01; T10: (0.24±0.21) μg/L vs. (1.09±0.55)μg/L, F=50.93, P=0.003, and NSE (T1: (1.22±0.32) μg/L vs. (0.47±0.23) μg/L, F=94.30, P<0.01;T3:(1.68±0.25) μg/L vs. (0.79±0.28) μg/L, F=78.63, P=0.017; T10: (0.98±0.37) μg/L vs. (0.51±0.22) μg/L, F=70.95, P=0.026) reached significant differences. Conclusions Plasma BDNF and NSE are closely related to the occurrence of delirium in critically ill patients, especially for BDNF. Clinical monitoring of plasma levels of BDNF can help to predict the outcome of brain function in critically ill patients.