A meta-analytic approach to mapping co-occurrent grey matter volume increases and decreases in psychiatric disorders

Numerous studies have investigated grey matter (GM) volume changes in diverse patient groups. Reports of disorder-related GM reductions are common in such work, but many studies also report evidence for GM volume increases in patients. It is unclear whether these GM increases and decreases are independent or related in some way. Here, we address this question using a novel meta-analytic network mapping approach. We used a coordinate-based meta-analysis of 64 voxel-based morphometry studies of psychiatric disorders to calculate the probability of finding a GM increase or decrease in one region given an observed change in the opposite direction in another region. Estimating this co-occurrence probability for every pair of brain regions allowed us to build a network of concurrent GM changes of opposing polarity. Our analysis revealed that disorder-related GM increases and decreases are not independent; instead, a GM change in one area is often statistically related to a change of opposite polarity in other areas, highlighting distributed yet coordinated changes in GM volume as a function of brain pathology. Most regions showing GM changes linked to an opposite change in a distal area were located in salience, executive-control and default mode networks, as well as the thalamus and basal ganglia. Moreover, pairs of regions showing coupled changes of opposite polarity were more likely to belong to different canonical networks than to the same one. Our results suggest that regional GM alterations in psychiatric disorders are often accompanied by opposing changes in distal regions that belong to distinct functional networks.

[Dyslipidemia and suicidal risk in patients with psychiatric disorders]

The aim of this work is to study the association between dyslipidemia and suicidal risk in patients with psychiatric pathology. Our study has involved 155 patients suffering from major depressive disorder and 124 schizophrenic patients aged 40.58±12.16 and 43.43±10.60 years, respectively. Total cholesterol (TC), triglycerides (TG) and HDL-c were determined by enzymatic methods, LDL-c was calculated by the Friedewald formula. Plasma cholesterol level was significantly lower among suicidal schizophrenic or depressive patients. There were no significant differences in the others lipid levels. The results of our study suggest that total cholesterol values less than 3.59mmol/L could be an indicator of suicide vulnerability in patients with schizophrenia or major depressive disorder.