Serum levels of brain-derived neurotrophic factor in drug-naive obsessive-compulsive patients: A case-control study

Background: There is lack of data regarding BDNF serum levels in patients with obsessive-compulsive disorder (OCD). The aims of the present study were: 1) to assess the serum BDNF content in a sample of drug-naive patients with OCD and 2) to assess whether putative alterations in peripheral BDNF may be associated to OCD severity and clinical characteristics. Methods: Twenty-four drug-naive patients with a principal diagnosis of OCD were recruited. In parallel, a control group of 24 unrelated volunteers matched for gender and age was enrolled. Serum BDNF levels were measured by ELISA method. Results: The results showed that BDNF levels were decreased in OCD patients when compared to controls (36.90 +/- 6.42 ng/ml versus 41.59 +/- 7.82 ng/ml: p = 0.043). No correlations were evidenced between serum BDNF content and the severity of OCD symptoms measured as Y-BOCS scores or other clinical variables. Limitations: The choice of drug-naive patients with obsessive-compulsive disorder had limited the size of the sample and excluded the recruitment of patients with a severe symptomatology. Conclusions: Our findings reveal for the first time in OCD patients a decrease in serum BDNF levels. These data corroborate the hypothesis of a dysfunction in the neurotrophin expression in the OCD pathogenetic mechanism and provide the rationale for further investigations directed to the identification of novel biomarkers and new therapeutic strategies for antiobsessional treatments. (C) 2009 Elsevier B.V. All rights reserved.