Higher Body-Mass Index and Lower Gray Matter Volumes in First Episode of Psychosis

Marián Kolenič; Filip Španiel; Jaroslav Hlinka; Martin Matějka; Pavel Knytl; Antonín Šebela; Jiří Renka; Tomas Hajek

doi:10.3389/fpsyt.2020.556759

Higher Body-Mass Index and Lower Gray Matter Volumes in First Episode of Psychosis

Front Psychiatry. 2020 Sep 23:11:556759. doi: 10.3389/fpsyt.2020.556759. eCollection 2020.

Authors

Marián Kolenič^{1

2}, Filip Španiel¹, Jaroslav Hlinka^{1

3}, Martin Matějka^{1

2}, Pavel Knytl^{1

2}, Antonín Šebela¹, Jiří Renka^{1

2}, Tomas Hajek^{1

4}

Affiliations

¹ Department of Applied Neuroscience and Neuroimaging, National Institute of Mental Health, Klecany, Czechia.
² 3rd Faculty of Medicine, Charles University, Prague, Czechia.
³ Department of Complex Systems, Institute of Computer Science of the Czech Academy of Sciences, Prague, Czechia.
⁴ Department of Psychiatry, Dalhousie University, Halifax, NS, Canada.

Abstract

Background: Neurostructural alterations are often reported in first episode of psychosis (FEP), but there is heterogeneity in the direction and location of findings between individual studies. The reasons for this heterogeneity remain unknown. Obesity is disproportionately frequent already early in the course of psychosis and is associated with smaller brain volumes. Thus, we hypothesized that obesity may contribute to brain changes in FEP.

Method: We analyzed MRI scans from 120 participants with FEP and 114 healthy participants. In primary analyses, we performed voxel-based morphometry (VBM) with small volume corrections to regions associated with FEP or obesity in previous meta-analyses. In secondary analyses, we performed whole-brain VBM analyses.

Results: In primary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in a) left fronto-temporal region (pTFCE = 0.008) and b) left postcentral gyrus (pTFCE = 0.043). When controlling for FEP, BMI was associated with lower GM volume in left cerebellum (pTFCE < 0.001). In secondary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in the a) cerebellum (pTFCE = 0.004), b) left frontal (pTFCE = 0.024), and c) right temporal cortex (pTFCE = 0.031). When controlling for FEP, BMI was associated with lower GM volume in cerebellum (pTFCE = 0.004). Levels of C-reactive protein, HDL and LDL-cholesterol correlated with obesity related neurostructural alterations.

Conclusions: This study suggests that higher BMI, which is frequent in FEP, may contribute to cerebellar alterations in schizophrenia. As previous studies showed that obesity-related brain alterations may be reversible, our ﬁndings raise the possibility that improving the screening for and treatment of obesity and associated metabolic changes could preserve brain structure in FEP.

Keywords: dyslipidemia; first-episode psychosis; low-grade inflammation; obesity; schizophrenia; voxel-based morphometry.