Brain-Derived Neurotrophic Factor and Delayed Verbal Recall in Crack/Cocaine Dependents

Abstract

Background/Aims: Considering the role of brain-derived neurotrophic factor (BDNF) in memory processes and its peripheral response during the detoxification of cocaine, the aim of this study was to investigate whether plasma BDNF levels could be related to memory performance in women with crack/cocaine dependence. Methods: Twenty-five abstinent female crack/cocaine users (CCD) and 25 unmedicated healthy women (HW), carefully matched for age and years of formal education, were assessed regarding memory performance. Logical Memory was used to assess the immediate verbal recall (IVR), delayed verbal recall (DVR) and memory retention. Plasma BDNF levels were measured by Elisa immunoassay. Beck Depression Inventory was used to assess the severity of depressive symptoms, and the Cocaine Selective Severity Assessment the severity of cocaine abstinence symptoms. Results: The CCD group had lower DVR scores and higher plasma BDNF levels when compared to HW group. In addition, a linear regression model showed that BDNF levels predicted DVR scores within CCD group independently of depressive symptoms (R = 0.51; R² = 0.26; t(22) = 4.025, p = 0.03). Conclusion: Despite higher plasma BDNF levels, crack users exhibited memory impairments when compared to healthy women. Specifically, peripheral BDNF levels predicted better cognitive performance only within individuals who already had cognitive impairment.