Is serum brain-derived neurotrophic factor related to craving for or use of alcohol, cocaine, or methamphetamine?

BACKGROUND Data suggests that brain-derived neurotropic factor (BDNF) plays a neuroadaptive role in addiction. Whether serum BDNF levels are different in alcohol or psychostimulants as a function of craving is unknown. Here, we examined craving and serum BDNF levels in persons with alcohol versus psychostimulant dependence. Our goals were to explore BDNF as an objective biomarker for 1) craving 2) abstinence, and 3) years of chronic substance use. METHODS An exploratory, cross-sectional study was designed. Men and women between 20-65 years old with alcohol, cocaine, or methamphetamine dependence were eligible. A craving questionnaire was used to measure alcohol, cocaine and methamphetamine cravings. Serum levels of BDNF were measured using enzyme linked immunoassay. Analysis of variance, chi-square, and correlations were performed using a 95% confidence interval and a significance level of P < 0.05. RESULTS We found a significant difference in the mean craving score among alcohol, cocaine and methamphetamine dependent subjects. There were no significant influences of race, gender, psychiatric disorder or psychotropic medication on serum BDNF levels. We found that among psychostimulant users BDNF levels were significantly higher in men than in women when the number of abstinent days was statistically controlled. Further, a significant correlation between serum BDNF levels and the number of abstinent days since last psychostimulant use was found. CONCLUSION These data suggest that BDNF may be a biomarker of abstinence in psychostimulant dependent subjects and inform clinicians about treatment initiatives. The results are interpreted with caution due to small sample size and lack of a control group.