Gray Matter Volume Decreases in Elderly Patients with Schizophrenia: A Voxel-based Morphometry Study

Background: Aged patients (>50 years old) with residual schizophrenic symptoms differ from young patients. They represent a subpopulation with a more unfavorable Kraepelinian course and have an increased risk (up to 30%) for dementia of unknown origin. However, our current understanding of age-related brain changes in schizophrenia is derived from studies that included less than 17% of patients who were older than 50 years of age. This study investigated the anatomical distribution of gray matter (GM) brain deficits in aged patients with ongoing schizophrenia. Methods: Voxel-based morphometry was applied to 3D-T1 magnetic resonance images obtained from 27 aged patients with schizophrenia (mean age of 60 years) and 40 age-matched normal controls. Results: Older patients with schizophrenia showed a bilateral reduction of GM volume in the thalamus, the prefrontal cortex, and in a large posterior region centered on the occipito-temporo-parietal junction. Only the latter region showed accelerated GM volume loss with increasing age. None of these results could be accounted for by institutionalization, antipsychotic medication, or cognitive scores. Conclusions: This study replicated most common findings in patients with schizophrenia with regard to thalamic and frontal GM deficits. However, it uncovered an unexpected large region of GM atrophy in the posterior tertiary cortices. The latter observation may be specific to this aged and chronically symptomatic subpopulation, as atrophy in this region is rarely reported in younger patients and is accelerated with age.