Computed tomography in the elderly: changes over time in a normal population

The clinical, psychometric, and computed tomographic (CT) status of previously fit elderly volunteers is described at follow-up for up to four years. A number of relationships were found between psychometric and CT scores, but a dementing group could not be determined on the basis of a single scan. However, a subtle reduction in cognition over time was significantly related to CT changes, and occurred in 10%. Larger ventricles were also found in a small sub-group, who developed late-onset depressive disorders; recent bereavement was related to ventricular size. Thus a single CT scan may not be a useful discriminatory test in early dementia, but a repeat demonstrating ventricular enlargement, is likely to be significant. In the elderly, cognitive and CT scan deterioration should not be expected unless a disease process is occurring; this may be indicated by subtle cognitive impairment or by late-onset depressive disorder.