Adolescents diagnosed with schizophrenia show greater decreases in gray matter volume and increases in cerebrospinal fluid in the frontal lobe when compared to healthy adolescents, and also when compared to patients suffering from bipolar disorder, according to a study published in the January issue of Archives of General Psychiatry.

“Progressive loss of brain gray matter (GM) has been reported in childhood-onset schizophrenia; however, it is uncertain whether these changes are shared by pediatric patients with different psychoses,” the authors wrote as background information in the study.

Celso Arango, MD, PhD, of the Hospital General Universitario Gregorio Marañón, Madrid, and colleagues examined the progression of brain changes in first-episode early-onset psychosis and the relationship to diagnosis and prognosis at two-year follow-up among patients at six child and adolescent psychiatric units in Spain. The authors performed MRI of the brain for 61 patients (25 diagnosed with schizophrenia, 16 with bipolar disorder and 20 with other psychoses) and 70 healthy control participants. MRI scans were conducted at study baseline and after two years of follow-up.

Compared with control patients, those diagnosed with schizophrenia showed greater GM volume loss in the frontal lobe during the two-year follow-up. Patients with schizophrenia showed losses of 3.3 cm³ and 3.7 cm³ in the left and right frontal lobes, respectively. Control patients had GM volume loss of less than 1 cm³ in both frontal lobes.

Significant differences existed in total GM loss as well, with schizophrenic patients showing a loss of 37.1 cm³ compared with a 14.5 cm³ loss in control subjects.

Patients with schizophrenia also showed cerebrospinal fluid increase in the left frontal lobe and changes in the left parietal GM that were significantly different from patients in the control group.

Among patients with schizophrenia, progressive brain volume changes in certain areas were related to markers of poorer prognosis, such as more weeks of hospitalization during follow-up and less improvement in negative symptoms. Greater left frontal gray matter volume loss was related to more weeks of hospitalization whereas severity of negative symptoms correlated with cerebrospinal fluid increase in patients with schizophrenia.

As for patients with bipolar disorder, the author did not find any significant changes between that group and control patients.

“In conclusion, we found progression of gray matter volume loss after a two-year follow-up in patients who ended up with a diagnosis of schizophrenia but not bipolar disease compared with healthy controls,” wrote the authors. “Some of these pathophysiologic processes seem to be markers of poorer prognosis. To develop therapeutic strategies to counteract these pathologic progressive brain changes, future studies should focus on their neurobiological underpinnings.”