Cognitive Functions and Impact of Plasma BDNF in Chronic Heroin Users

Abstract

Background: Recent evidence suggests that abusing drugs may alter the normal structure in brain regions and influence functions that induce cognitive deficits and promote continued drug use. Objective: The objective of this study was to assess the pattern of cognitive dysfunctions in patients with chronic heroin use and to explore any relation to brain-derived neurotrophic factor (BDNF) plasma level. Method: This was a case-control naturalistic cross-sectional study of 50 patients (case group) with chronic heroin use according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) who were recruited from the inpatient unit and outpatient clinics of Institute of Psychiatry, Ain Shams University, and were further compared with a control group that consisted of 38 frequency-matched healthy volunteers. The groups were subjected to the following: (1) clinical psychiatric examination, (2) Structured Clinical Interview for DSM-IV (SCID-I), (3) Addiction Severity Index for the patients’ group, (4) Wechsler Adults Intelligence Scale, (5) Wechsler Memory Scale, (6) Wisconsin Card Sorting Test—computerized version was performed to assess cognitive functions, and (7) measuring BDNF plasma level. Results: Definite cognitive function impairment and poor cognitive domains were detected among the case group. Total intellectual functions, and visual, verbal, immediate memory, and executive functions were statistically significant (P<0.005). Although, there was no significance between BDNF plasma level and different neurocognitive functions, higher BDNF plasma level among the case group was detected. Limitation: Premorbid cognitive abilities could not be assessed, as the current study was a cross-sectional study. Conclusions: Those with chronic heroin use suffer from cognitive dysfunction of multiple domains that may contribute to their continued drug use. Psychotherapeutic programs should consider these findings in their approaches for better impact on patients’ quality of life and overall treatment outcome.