Combined Grey Matter VBM and White Matter TBSS Analysis in Young First Episode Psychosis Patients With and Without Cannabis Consumption

Abstract

Cannabis consumption is temporally associated with the development of first episode psychosis (FEP). Whether or not the chronic use of this substance induces structural brain changes that may be responsible for the cognitive and psychological disturbances in this disorder is still matter of debate. To address this issue, we compared the magnetic resonance imaging (MRI)-assessed grey (GM) and white matter (WM) changes in young FEP patients between users versus non-users of cannabis. This prospective study included 50 consecutive FEP subjects: 33 users (22.7 ± 4.1 years, 4 women) and 17 non-users (23.9 ± 4.2 years, 10 women). Users were further divided into 15 heavy (23.3 ± 4.5 years, 2 women) and 18 light users (22.2 ± 3.8 years, 2 women) according to their lifetime cannabis use. Voxel-based-morphometry (VBM) analysis of GM and tract-based-spatial-statistics (TBSS) analysis of WM were performed. Age and gender were used as non-explanatory co-regressors. There were no supra-threshold differences between user and non-user groups for both GM and WM parameters. This was also the case when only heavy users were compared to non-users. Multivariate models controlling for age and gender confirmed these findings. We found no evidence for cannabis consumption related alterations in GM or WM in FEP subjects. Due to the strict correction for multiple comparisons and sample size, we cannot formally exclude subtle morphometric changes associated with cannabis consumption. However, even if present, such potential alterations would be of low magnitude.

Effect of high-potency cannabis on corpus callosum microstructure

“…( 2011 ) found that early cannabis use in adolescent-onset schizophrenia was associated with lower FA in the brain stem, internal capsule, corona radiata, and superior and inferior longitudinal fasciculi. Finally, a recent study in FEP patients found no brain-wide differences in grey matter or WM between lifetime heavy and light users, or non-users (Haller et al 2013 ). Several methodological differences may explain these inconsistencies.…”

Brain volume in male patients with recent onset schizophrenia with and without cannabis use disorders

“…10 The use of a more homogeneous sample (i.e., including only patients with recent onset schizophrenia) would diminish these con founding effects, but so far few studies in patients with re cent onset schizophrenia have been published. Some studies show smaller volumes in the CUD group, [12][13][14][15] whereas oth ers found no volumetric differences between patients with and without (NCUD) CUDs [16][17][18][19][20] or an increase in grey matter…”

Linked alterations in gray and white matter morphology in adults with high-functioning autism spectrum disorder: A multimodal brain imaging study

“…In an effort to investigate such possibilities, several recent studies have adopted a new approach in which multimodal brain imaging data are collected from the same subject. Indeed, multimodal brain imaging is increasingly playing important roles in revealing structural–structural (i.e., gray and white matters) or structural–functional associations in normal ( Ethofer et al, 2011 ; Li et al, 2013 ) and clinical populations, including Alzheimer's disease ( Jacobs et al, 2012 ), schizophrenia ( Schlosser et al, 2007 ), autism ( Beacher et al, 2012 ; Mengotti et al, 2011 ), and other diseases ( Ambrosi et al, 2013 ; Haller et al, 2013 ; Quinque et al, 2012 ; Ruef et al, 2012 ). For instance, Kana et al (2014) acquired functional MRI (fMRI) data during a social cognition task and DTI data from each individual with ASD and normal control; the multimodal data were analyzed separately, and then combined together only when interpreting resultant statistical maps.…”