MRI in successful aging, a 5-year follow-up study from the eighth to ninth decade of life

This study aimed at evaluate the effect of aging on the central nervous system in "successfully aged" elderly subjects. The brain was studied with magnetic resonance imaging and neuropsychological tests at three different occasions during a time period of 5 yr.

Twenty-four successfully aged elderly were repeatedly examined with cerebral MRI and neuropsychological tests. The first examinations were performed in 1987 and then followed-up in 1989 and 1993. Two different MRI systems were used, in 1987 and 1989, a system operating at 0.02 T and in 1993 a system operating at 0.5 T. Ten subjects (42%) did not participate in the follow-up studies. MRI was used to study the degree of and increase in signal hyperintensities in the cerebrum, the basal ganglia, and in the infratentorial areas as well as changes in the volumes of the cerebro spinal fluid (CSF) spaces.

At the start of the study in 1987, mild signal hyperintensities were observed in 11 of the 13 subjects who completed the follow up study. A modest increase in signal hyperintensity was found in almost all of the subjects, with the increases in cerebral white matter and basal ganglia signal hyperintensity being statistically significant (p < .03 and p < .05). The increases in periventricular hyperintensity and the hyperintensity from the infratentorial areas did not reach statistical significance. Volumes of the lateral ventricles and the frontal CSF spaces increased significantly (p < .03 in both cases) during the observation period, whereas the other volumes remained unchanged. The neuropsychological tests were unchanged during the observation period with the exception of the psychomotor capacity, which deteriorated. No statistical significant correlations were seen between the degree of or increase in signal hyperintensities and results from any of the neuropsychological tests.

During a 5-yr observation of successfully aged elderly it was found that there was a mild increase in signal hyperintensity in the cerebral white matter and basal ganglia, as well as an increase in the frontal and ventricular CSF volumes. These changes were not related to changes in psychometric test results, nor were they related to the clinical outcome during the time of observation.