Progressive structural brain changes during development of psychosis.

Background: Ultra-high risk (UHR) for psychosis has been associated with widespread structural brain changes in young adults. The onset of these changes and their subsequent progression over time are not well understood.

Methods: Rate of brain change over time was investigated in 43 adolescents at UHR for psychosis compared with 30 healthy controls. Brain volumes (total brain, gray matter, white matter [WM], cerebellum, and ventricles), cortical thickness, and voxel-based morphometry were measured at baseline and at follow-up (2 y after baseline) and compared between UHR individuals and controls. Post hoc analyses were done for UHR individuals who became psychotic (N = 8) and those who did not (N = 35).

Results: UHR individuals showed a smaller increase in cerebral WM over time than controls and more cortical thinning in the left middle temporal gyrus. Post hoc, a more pronounced decrease over time in total brain and WM volume was found for UHR individuals who became psychotic relative to controls and a greater decrease in total brain volume than individuals who were not psychotic. Furthermore, UHR individuals with subsequent psychosis displayed more thinning than controls in widespread areas in the left anterior cingulate, precuneus, and temporo-parieto-occipital area. Volume loss in the individuals who developed psychosis could not be attributed to medication use.

Conclusion: The development of psychosis during adolescence is associated with progressive structural brain changes around the time of onset. These changes cannot be attributed to (antipsychotic) medication use and are therefore likely to reflect a pathophysiological process related to clinical manifestation of psychosis.