CEREBRAL GLUCOSE-METABOLISM IN CHILDHOOD-ONSET SCHIZOPHRENIA

Decreased frontal cortical glucose metabolism has been demonstrated in adult schizophrenics both at rest and while engaging in tasks that no rmally increase frontal metabolism, such as the Continuous Performance Test (CPT). The authors tested the hypothesis that adolescents with c hildhood onset schizophrenia would also demonstrate hypofrontality whi le performing the CPT. Cerebral glucose metabolism was examined in 16 adolescents (mean age 14.1 +/- 1.7) with onset of schizophrenia by age 12 (mean age at onset 9.9 +/- 1.8) and 26 healthy adolescents selecte d to be similar in age, sex and handedness using positron emission tom ography and F-18-fluorodeoxyglucose. Patients with childhood onset sch izophrenia made fewer correct and more incorrect identifications on th e CPT. Region of interest analysis revealed no significant group diffe rences in global cerebral glucose metabolism, but increased metabolic rate in supramarginal gyrus (F = 6.74, P < 0.05) and inferior frontal gyrus/insula (F = 7.09, P < 0.05) and decreased metabolic rate in midd le frontal gyrus (F = 6.72, P<0.05) and superior frontal gyrus (t=2.04 , P<0.05) in schizophrenics. Comparison of effect sizes with an identi cally designed study of adult schizophrenics did not indicate more sev ere hypofrontality in childhood onset schizophrenia. Pixel-based analy ses indicated a more complex pattern of group differences in cerebral metabolism with bilaterally increased cerebellar metabolic rate in chi ldhood onset schizophrenics. These findings suggest that childhood ons et schizophrenia may be associated with a similar, but not more severe , degree of hypofrontality relative to that seen in adult onset schizo phrenia. (C) 1997 Elsevier Science Ireland Ltd.