Internal capsule integrity and its sex-related structural differences in early-onset schizophrenia – diffusion tensor imaging study

Piotr Chomczyński

Ministry of Science and Higher Education

Objectives: In schizophrenia, the most repeatable DTI findings concern reduced FA in temporal and frontal lobes with associated abnormalities in connecting neural fibers. The goal of study was to evaluate the differences in FA of the internal capsule in EOS-patients and healthy controls and to place emphasis on the sex as a potential factor determining a predominant pathological pattern of described changes. Methods: 30 EOS patients and 30 healthy controls were studied using DTI. FA measures within internal capsules were performed in selected ROIs. For statistical analyses the one-way ANOVA test was used (p<0.05). Results: Significant differences of FA between EOS-patients and controls in the right ALIC with lower values of FA in EOS were observed. Within the women sub-groups, statistical differences of FA were observed only for the right ALIC. There were no statistically significant differences within men sub-groups.

Presence of statistically significant differences in the WM diffusivity of the brain in the right ALIC region between the EOS patients and the control group was found. Differences in tissues diffusivity were observed exclusively in the subgroups of women, which suggests that the final results of the comparison of groups largely depend on the variability found in the women-subgroup. The lack of statistically significant differences in diffusion in men – with repeatedly confirmed higher frequency of schizophrenia diagnoses in this age group of boys – suggests that ALIC may be less important for determining the development of the disease in males. The results of the study are one of the first findings which indicate possible involvement of the structures of the internal capsule in the development of EOS.