A significant cortical thinning has been repeatedly observed in adult-onset first-episode schizophrenia patients compared to healthy controls, mostly in medial and inferior prefrontal cortices. However, it is yet unclear whether all these replicated alterations are related to any particular clinical feature.

This study aimed to investigate differences of cortical thickness in a sample of first-episode, drug-naive psychotic patients and age- and gender-matched healthy controls and explore clinical correlates of these parameters regarding negative symptoms.

High-resolution T1-weighted images were acquired from 23 antipsychotic-naive, first-episode psychotic patients and 26 age-matched healthy comparison subjects. Clinical features were measured with the negative subscale of the Positive and Negative Syndrome Scale (PANSS) at baseline and after a 2-month follow-up period.

No differences were found regarding age or gender when comparing patients and controls. We found a significant cortical thinning in the left medial orbitofrontal cortex and in the right lateral orbitofrontal cortex in patients compared to healthy age- and gender-matched controls. Regarding clinical performance, no correlation was found at baseline between left medial orbitofrontal nor right lateral ortitofrontal cortical thickness and scores of the negative subscale of the PANSS. However, at the 2-month evaluation clinical performances were significantly associated to the left medial orbitofrontal cortical thickness values.

Cortical thickness alterations in prefontal cortex appear to be present at disease onset and these alterations may relate to clinical outcome. However, our findings must be considered just as exploratory. Larger longitudinal studies may help characterize, replicate and consolidate these findings.

The authors have not supplied their declaration of competing interest.