Cerebral white matter changes in deficit and non-deficit subtypes of schizophrenia

The considerable clinical heterogeneity in schizophrenia makes elucidation of its neurobiology challenging. Subtyping the disorder is one way to reduce this heterogeneity and deficit status is one such categorization based on the prominence of negative symptoms. We aimed to utilize diffusion tensor imaging (DTI) to identify unique white matter cerebral changes in deficit schizophrenia (DS) compared with non-deficit schizophrenia (NDS) and healthy controls (HC) in an Asian sample. A total of 289 subjects (111 HC, 133 NDS and 45 DS) underwent DTI and completed rating scales which assessed the severity of psychopathology, psychosocial functioning and premorbid intelligence.We found that DS patients had fractional anisotropy (FA) reductions in the Body of the Corpus Callosum (BCC) and right Posterior Thalamic Radiation (PTR) regions relative to HCs, and FA reductions in the right PTR relative to NDS patients. NDS patients had FA reductions of the BCC and right PTR relative to HCs. Binomial logistic regression analyses revealed that FA reductions of the right PTR FA was an independent predictor of deficit status. The identified brain white matter changes especially in the PTR relate to deficits of cognitive control and emotional awareness, which may underlie psychopathology associated with deficit status like inattention and affective blunting. These potential biomarkers of DS warrant further examination to determine their utility for monitoring illness progression and intervention response in schizophrenia.