Whole brain volume changes and its correlation with clinical symptom severity in patients with schizophrenia: A DARTEL-based VBM study

Abstract

The purpose of this study was to evaluate gray matter (GM) and white matter (WM) volume alterations in whole-brain structures in patients with schizophrenia and healthy controls using voxel-based morphometry (VBM), and further to assess the correlation between GM and WM volume variations and symptom severity in schizophrenia. A total of 22 patients with schizophrenia and 22 age-matched healthy controls participated. Magnetic resonance image data were processed using SPM8 software with diffeomorphic anatomical registration via an exponentiated Lie algebra (DARTEL) algorithm. Patients with schizophrenia exhibited significantly decreased GM volumes of the insula, superior temporal gyrus (STG), gyrus rectus, and anterior cingulate cortex (ACC) compared with healthy controls. The GM volumes of the STG and gyrus rectus were negatively correlated with the positive scales on the Positive and Negative Syndrome Scale (PANSS) and those of the STG and ACC were negatively correlated with the negative scales. The durations of illness in schizophrenia were negatively correlated with the GM volumes of the insula, STG, and ACC. Patients with schizophrenia exhibited significantly decreased WM volumes of the superior frontal gyrus, inferior temporal gyrus, and STG. The WM volumes of the STG were negatively correlated with the duration of illness. Our findings suggest that GM and WM volume abnormalities in the STG are associated with the psychopathology of schizophrenia.

Fig 1. Decreased gray matter volumes and its correlation with clinical symptom severity in patients with schizophrenia compared with healthy controls.

The patients with schizophrenia (n = 22) exhibited significantly lower GM volumes of the insula, STG, gyrus rectus, and ACC compared with the healthy controls (n = 22) (p<0.05, FWE) (A). The color-coded pixels were scaled to the range more than cut-off threshold (p<0.05). The GM volumes of the STG (p = 0.005) and gyrus rectus (p = 0.007) were negatively correlated with the positive scales (B) in the positive and Negative Syndrome Scale (PANSS) and those of the STG (p = 0.023) and ACC (p = 0.024) were negatively correlated with the negative scales (C). STG, superior temporal gyrus; ACC, anterior cingulate cortex. ¹Spearman's rho. *p<0.05, **p<0.01, ***p<0.001.

Fig 2. Decreased white matter volumes in patients with schizophrenia compared with healthy controls.

The patients with schizophrenia (n = 22) exhibited significantly lower WM volumes of the SFG, ITG, and STG compared with the healthy controls (n = 22) (p<0.0001, uncorrected). The color-coded pixels were scaled to the range more than cut-off threshold (p<0.0001). SFG, superior frontal gyrus; ITG, inferior temporal gyrus; STG, superior temporal gyrus.

Fig 3. Correlations of the GM and WM volumes with the duration of illness in patients with schizophrenia.

The GM volumes of the insula (ρ = -0.43, p = 0.044), STG (ρ = -0.53, p = 0.012), and ACC (ρ = -0.51, p = 0.015) were negatively correlated with the duration of illness in patients with schizophrenia. The WM volumes of the STG (ρ = -0.43, p = 0.047) were negatively correlated with the duration of illness in patients with schizophrenia. STG, superior temporal gyrus; ACC, anterior cingulate cortex. ¹Spearman's rho. *p<0.05.

Fig 4. Gender difference in gray matter volumes in patients with schizophrenia.

The female patients (n = 10) showed significantly lower GM volumes of the dlPFC compared with male patients (n = 12) (p<0.0001, uncorrected) (A). The color-coded pixels were scaled to the range more than cut-off threshold (p<0.0001). Box-plots show the medians, interquartile ranges, and the highest and lowest values of GM density of the dlPFC in male and female patients with schizophrenia (B). dlPFC, dorsolateral prefrontal cortex.