Reduction of cerebral blood flow in chronic schizophrenia: relation to age.

The effect of age on resting-state cerebral blood flow (CBF) was studied in 40 medicated patients with chronic schizophrenia aged 20 to 57 and 32 age- and sex-matched normal controls, using the regional CBF with the xenon-133 inhalation technique. Global CBF (average of 16 cerebral regions) and the left prefrontal flow ratio (left prefrontal/global CBF) were significantly lower in schizophrenics aged 20-29 than in age-matched controls. Both global CBF and the left prefrontal flow ratio correlated with age in controls, but neither of such correlations was found in schizophrenics. Therefore, the CBF deficits in chronic schizophrenia appear to be unaffected by the aging process.