title: Suicidal attempts and increased right amygdala volume in schizophrenia.
abstract: Suicide is a major cause of death in schizophrenia. Neurobiological studies suggest that suicidality is associated with abnormal brain structure and connectivity in fronto-temporo-limbic regions. However, it is still unclear whether suicidality in schizophrenia is related to volumetric abnormalities in subcortical structures that play a key role in emotion regulation, aggression and impulse control. Therefore, we aimed to examine whether the volume of selected subcortical regions is associated with previous suicidal attempts and self-aggression in schizophrenia. For this cross-sectional study, we recruited 50 outpatients with schizophrenia and 50 healthy controls (HC) matched for age and gender. Fourteen patients had a history of one or more suicide attempts. Different forms of aggression were assessed using the Modified Overt Aggression Scale. All participants underwent structural MR imaging at 3 Tesla. Physical volumetric measures were calculated for the lateral ventricles, thalamus, hippocampus, amygdala, caudate, putamen, pallidum and accumbens using an automatic segmentation method on T1-weighted high-resolution (voxel size 1×1×1mm(3)) images. Multivariate and follow-up univariate ANOVAs revealed a selective increase in volume in the right amygdala of patients with a history of suicidality compared both to patients without such a history and HC. Moreover, in the entire patient group increased right amygdala volume was related to increased self-aggression. Our findings suggest that right amygdala hypertrophy may be a risk factor for suicide attempts in patients with schizophrenia and this could be relevant for suicide prevention.
authors.affiliation: IRCCS Santa Lucia Foundation, Rome, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Spoletini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Piras
authors.forename: Sabrina
authors.initials: S
authors.lastname: Fagioli
authors.forename: Ivo Alex
authors.initials: IA
authors.lastname: Rubino
authors.forename: Giovanni
authors.initials: G
authors.lastname: Martinotti
authors.forename: Alberto
authors.initials: A
authors.lastname: Siracusano
authors.forename: Carlo
authors.initials: C
authors.lastname: Caltagirone
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Spalletta
mesh_terms: D000328:Adult; D000679:Amygdala / Q000473:pathology*; D000704:Analysis of Variance; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000473:pathology*; D012565:Schizophrenic Psychology; D013223:Statistics as Topic; D013406:Suicide, Attempted / Q000523:psychology*; D055815:Young Adult