Serum glial cell line-derived neurotrophic factor levels and impulsivity in heroin addiction: a cross-sectional, case-control study of 129 heroin addicts

OBJECTIVE: Glial cell line-derived neurotrophic factor (GDNF), being a protective of dopaminergic neurons, is reported to modulate addictive behaviours and have a role as a negative regulator for biochemical and behavioural adaptations to drug abuse. We aimed to reveal impulsivity and serum GDNF levels in patients with heroin addiction and investigate their relationships in order to contribute to the understanding of behavioural aspects and biological mechanisms in heroin addiction via this study. METHODS: This study was performed at the Department of Psychiatry of Ankara Numune Training and Research Hospital, Turkey. We recruited 129 heroin-dependent patients and 90 age, sex, and smoking-matched healthy controls with no major psychopathology. Barratt Impulsivity Scale-11, Hospital Anxiety and Depression Scale (HADS) and sociodemographic data form were applied to all participants. Laboratory analysis for serum GDNF levels was performed for each participant's blood sample. RESULTS: Total impulsivity scores and scores of Attentional Impulsivity, Motor Impulsivity, and Unplanned Impulsivity subscales were all higher in heroin addicts compared to the controls. Heroin addicts had also lower serum GDNF levels and lower GDNF levels were associated with high impulsivity and high HADS scores in heroin addicts. CONCLUSION: Decrement in GDNF levels in heroin addiction seems as to be an important data which could be associated with impulsivity, anxiety, and depressive symptoms. GDNF could find a prominent place among the target molecules in the treatment of heroin addiction