Gender, Brain-Derived Neurotrophic Factor Val66Met, and Frequency of Methamphetamine Use

Background: Frequency of pretreatment methamphetamine (MA) use is an important predictor of outcomes of treatment for MA dependence. Preclinical studies suggest females self-administer more MA than males, but few clinical studies have examined potential sex differences in the frequency of MA use. Estrogen increases expression of brain-derived neurotrophic factor (BDNF), which has effects on MA-induced striatal dopamine release and protects against MA-induced neurotoxicity. Objective: We examined potential effects of sex, the Val66Met polymorphism in BDNF, and their interaction on frequency of MA use among 60 Caucasian MA-dependent volunteers screening for a clinical trial. Methods: Data was taken from 60 Caucasian MA-dependent volunteers screening for a clinical trial. Results: Females reported significantly more pretreatment days with MA use in the past 30 days than males. There was a significant interaction between sex and BDNF Val66Met, with the highest frequency of MA use among females with Val/Val genotype. Conclusions: These results, although preliminary, add to the literature documenting sexual dimorphism in response to stimulants, including MA, and suggest a potential biological mechanism involving BDNF that might contribute to these differences. Additional research characterizing the biological basis of altered response to MA among females is warranted. (Gend Med. 2012;9:112-120) (C) 2012 Elsevier HS Journals, Inc. All rights reserved.