Serum brain-derived neurotrophic factor and nerve growth factor decreased in chronic ketamine abusers

Aims: This study investigated the serum levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in a group of chronic ketamine abusers in comparison to healthy controls. The correlations between the serum BDNF, NGF level with the subjects' demographic, pattern of ketamine use were also examined. Methods: 93 subjects who met the criteria of ketamine dependence and 39 healthy subjects were recruited. Serum BDNF and NGF levels were assayed by enzyme-linked immunosorbent assay (ELISA). Psychopathological symptoms were assessed using Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). Results: Both serum levels of BDNF and NGF were significant lower in the ketamine users compared to the healthy control subjects (9.50 +/- 6.68 versus 14.37 +/- 6.07 ng/ml, p = 0.019 for BDNF; 1.93 +/- 0.80 versus 2.60 +/- 1.07 ng/ml, p = 0.011 for NGF). BDNF level was negatively associated with current frequency of ketamine use (r = -0.209, p = 0.045). Conclusions: Both BDNF and NGF serum concentrations were significantly lower among chronic ketamine users than among health controls. (C) 2014 Elsevier Ireland Ltd. All rights reserved.