Basal ganglia subregion volume changes between acute-phase schizophrenia and bipolar disorder

Background and Hypothesis: Schizophrenia (SCZ) and bipolar disorder (BD) have a certain degree of overlap in terms of diagnosis, pathophysiology, and genetic levels, which may be related to the existence of similar biological backgrounds in both, especially when psychosis symptoms are present. Study Design: This study included 90 patients with SCZ, 60 patients with psychotic bipolar disorder (P-BD), 22 patients with non-psychotic bipolar disorder (NP-BD) (all patients were acute-phase patients with a disease duration of less than 5 years), and 100 healthy control (HC) group, who all underwent structural magnetic resonance imaging (MRI) scans. Covariance analysis was performed using SPSS 26.0 to compare the differences in basal ganglia volume between the groups. Study Results: The results showed significant differences in the volumes of the left putamen (F=6.511, P=0.002), right putamen (F=5.416, P=0.005), left pallidum (F=29.920, P<0.001), and right pallidum (F=12.513, P<0.001) in the SCZ group, P-BD group and HC group. Meanwhile, there were significant differences in the volumes of the left pallidum (F=6.776, P=0.001) and right putamen (F=9.930, P<0.001) in the P-BD group, NP-BD group and HC group. Conclusions: We found a significant difference between P-BD and SCZ, but no such difference was observed between P-BD and NP-BD, although the observed difference between groups may be partly attributable to exposure to antipsychotic medications.