Smaller hippocampal volume in current but not in past depression in comparison to healthy controls: Minor evidence from an older adults sample.

BACKGROUND: Structural neuroimaging studies revealed a consistent pattern of volumetric reductions in both hippocampus (HC) and anterior cingulate cortex (ACC) of individuals with major depressive episode(s) (MDE). This study investigated HC and ACC volume differences in currently depressed individuals (n = 150), individuals with a past lifetime MDE history (n = 79) and healthy controls (n = 287). METHODS: Non-demented individuals were recruited from a cohort of community-dwelling older adults (ESPRIT study). T1-weighted magnetic resonance images and FreeSurfer Software (automated method) were used. Concerning HC, a manual method of measurement dividing HC into head, body, and tail was also used. General Linear Model was applied adjusting for covariates. RESULTS: Current depression was associated with lower left posterior HC volume, using manual measurement, in comparison to healthy status. However, when we slightly changed sub-group inclusion criteria, results did not survive to correction for multiple comparisons. CONCLUSIONS: The finding of lower left posterior HC volume in currently depressed individuals but not in those with a past MDE compared to healthy controls could be related to brain neuroplasticity. Additionally, our results may suggest manual measures to be more sensitive than automated methods.

The link between dissociation and both suicide attempts and non-suicidal self-injury: Meta-analyses.

Dissociative disorders (DD) are frequently associated with suicidal behaviors. We performed the first meta-analysis of studies comparing rates of suicide attempts (SA) and non-suicidal self-injury (NSSI) in psychiatric individuals with and without DD. We included: 1) studies comparing SA and NSSI rates in psychiatric individuals with and without DD; 2) studies comparing Dissociative Experiences Scale (DES) scores in both SA and NSSI psychiatric patients versus non SA and non NSSI ones. Cochrane Collaboration Review Manager Software and STROBE statement were used. Nineteen studies were included in the analyses. DD patients were more likely to report both previous SA and NSSI in comparison to non DD patients. Importantly, results remained highly significant in both outcomes but with no more heterogeneity when including studies using a DSM-based method to diagnose DD. Both SA and NSSI patients reported higher DES scores in comparison to non SA and non NSSI patients. The presence of DD diagnosis or higher DES scores seems to be related to both SA and NSSI in psychiatric patients. Hence, it may be reasonable to hypothesize the presence of a dissociative subtype in a subset of these patients, which should be considered as a transdiagnostic factor and should be carefully assessed.