Pediatric psychosis patients show increased grey matter loss
MedWire News: Children and adolescents with first-episode psychosis show increased levels of gray matter (GM) volume loss compared with their mentally healthy peers, say Spanish researchers.
Writing in the Archives of General Psychiatry, Celso Arango (Centro de Investigación Biomédica en Red de Salud Mental, Madrid) and colleagues explain that "a progressive loss of cortical GM volume and an abnormal increase in ventricular volume have… been described in studies of adolescent patients with childhood-onset schizophrenia."
But they add: "It is uncertain whether these changes are shared by pediatric patients with different psychoses."
To investigate, the team studied 61young people, aged 7-17 years, with first-episode, early-onset psychosis and 70 mentally-healthy individuals (controls) who were of similar age, parental socioeconomic status, education level, and gender distribution.
All of the participants underwent magnetic resonance imaging (MRI) of the brain at baseline and after 2 years of follow-up. Of the patients with psychosis, 41.0% were diagnosed with schizophrenia, 26.2% with bipolar disorder, and 33.8% with "other" psychoses at follow-up.
Comparison of baseline and follow-up data revealed that psychosis patients who were diagnosed with schizophrenia showed significantly greater total GM volume loss over time than controls, at -37.1 versus -14.5 cm3.
In addition, patients diagnosed with schizophrenia showed greater GM volume loss than controls in the left (-3.3 vs -0.6 cm3) and right frontal lobes (-3.7 vs -0.8 cm3), and the left parietal lobe (-4.3 vs -2.2 cm3), and increases in left frontal cerebrospinal fluid (CSF) volumes (at 6.7 vs 4.1 cm3).
Greater levels of GM volume loss were associated with a higher number of hospitalizations, and CSF volume increases were positively associated with negative symptom severity in schizophrenia patients.
Patients with other psychoses also showed greater total GM volume loss than controls, albeit to a lesser extent than schizophrenia patients, as well as GM reductions in the frontal bilateral and left parietal lobes, and greater increases in CSF volume in the frontal lobes.
However, there were no significant differences in GM and CSF volume between bipolar disorder patients and controls over time, the researchers note.
Arangoand team conclude: "Patients who ended up with a diagnosis of schizophrenia showed greater progressive brain changes than healthy controls in the 2-year follow-up period after the first psychotic episode. In the patients with schizophrenia, progressive volume changes in certain brain areas were related to markers of poorer prognosis."
They add: "To develop therapeutic strategies to counteract these pathologic progressive brain changes, future studies should focus on their neurobiological underpinnings.
"The correlates of volume changes at a cellular level and the study of risk genes involved in circuitries associated with different psychoses and their relationship to developmental trajectories may be promising areas of research."
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By Mark Cowen