Antidepressant effects of sertraline associated with volume increases in dorsolateral prefrontal cortex

Abstract

Background: Structural brain imaging has revealed differences in gray matter volume between depressed individuals and control subjects in key structures related to emotion. The aim of the present study was to assess within subjects whether regional changes in gray matter volume were observed over time in depressed patients treated with sertraline.

Methods: Thirteen depressed patients were assigned to selective serotonin reuptake inhibitor (SSRI) treatment with sertraline. Structural magnetic resonance imaging (MRI) was performed at four time points over 12 weeks of treatment. Depressed individuals were compared to a control group of 10 subjects scanned at the same time points using voxel based morphometry and a statistical growth modeling technique.

Results: SSRI-treated patients showed a region of significantly increasing gray matter volume over time within the left dorsolateral prefrontal cortex (DLPFC) that specifically correlated with decreases in self-reported depression levels. No statistically significant changes were observed related to time in controls.

Limitations: This study included a small sample size and the method of analysis was capable of detecting only linear changes in volume.

Conclusions: Effective antidepressant treatment with sertraline is associated with left DLPFC volume increases. These volume increases may reflect cortical architectural changes associated with top-down neuronal modulation of emotion.