Differences in brain surface area and cortical volume between suicide attempters and non-attempters with major depressive disorder

•We investigated the differences in brain surface area and cortical volume between suicide attempters and nonsuicide attempters with MDD using FreeSurfer program.•There was larger cortical surface area of the left postcentral and left lateral occipital area and smaller left superior frontal area in suicide attempters than non-attempters.•There was larger cortical volume of the left postcentral area and left lateral orbitofrontal area in suicide attempters than non-attempters. The neurobiological causes underlying suicidal behaviors in major depressive disorder (MDD) have not been identified. This study was performed to investigate the differences in brain cortical thickness, surface area, and volume between suicide attempters and non-attempters with MDD. We performed magnetic resonance imaging (MRI) in 38 MDD patients (18–65 years old; 18 male, 20 female) with and without a history of suicide attempts. FreeSurfer software was used to compare the cortical thickness, surface area, and volume of 19 suicide attempters with MDD and 19 suicide non-attempters with MDD, while controlling for age, sex, mean area (or volume), and severity of depression. Compared with suicide non-attempters, suicide attempters with MDD exhibited a larger surface area in the left postcentral area and left lateral occipital area and a larger cortical volume in the left postcentral area and left lateral orbitofrontal area. Suicide attempters exhibited a smaller surface area in the left superior frontal area than suicide non-attempters. The present findings provide evidence for neuroanatomical risk factors of suicide in MDD. Further research to replicate these results and determine the mechanisms underlying these findings is needed.