Evaluation of the regional cerebral blood flow changes during long-term donepezil therapy in patients with Alzheimer's disease using 3DSRT.

BACKGROUND

We attempt to evaluate objectively the regional cerebral blood flow (rCBF) changes during long-term donepezil therapy and the relationship between the clinical response and rCBF change in patients with Alzheimer's disease (AD).

PATIENTS AND METHODS

Thirty-one patients with mild-to-moderate AD (11 men, 20 female; mean age, 76.2 ± 6.7 years) were treated with donepezil and underwent brain perfusion single-photon emission computed tomography (SPECT) twice with an interval of 24.5 ± 4.2 months. The rCBF was calculated using 3-dimensional stereotaxic region of interest template, a fully automated each region of interest technique. We compared the differences in rCBF between baseline and follow-up SPECT studies. Moreover, all patients were divided into stabilized (n = 14) and nonstabilized subgroups (n = 17) based on Mini-Mental State Examination (MMSE) score changes and the changes in rCBF were compared between two subgroups.

RESULTS

The mean MMSE score significantly decreased from 20.7 ± 4.6 at baseline to 16.5 ± 6.5 after 2 years. The mean rCBF significantly decreased in the widespread brain regions between the baseline and follow-up SPECT studies. The nonstabilized subgroup showed a significant decrease in rCBF of the parietal and temporal segments compared to the stabilized subgroup.

CONCLUSION

The progression of cognitive deterioration may be related to rCBF affected by the neuropathologic changes of AD.