To examine the importance of ghrelin and leptin in the pathogenesis of obsessive-compulsive disorder (OCD), we measured serum ghrelin and leptin levels, lipid profile and body mass index (BMI) in 43 patients with OCD and 20 healthy controls. The patients were divided into two subgroups according to whether DSM-IV OCD was accompanied with major depressive disorder (MDD) (OCD + MDD) or not (OCD - MDD). There was no statistically significant difference in ghrelin and leptin levels between groups. The OCD + MDD group had a trend of higher ghrelin levels and lower leptin levels than the OCD - MDD and control groups. There was a negative correlation between change in serum ghrelin and leptin levels only in the OCD + MDD group. Neither ghrelin nor leptin showed any correlation with severity of MDD and OCD. In conclusion, our results suggest that OCD is not associated with leptin or ghrelin levels. More comprehensive and detailed studies are needed to decipher the exact role of ghrelin and leptin in OCD. (C) 2007 Elsevier Inc. All rights reserved.