EFFECT OF MEMANTINE ON BEHAVIORAL AND PSYCHOLOGICAL SYMPTOMS OF DEMENTIA (BPSD) OF ALZHEIMER'S DISEASE - STUDY OF CHANGES IN CEREBRAL BLOOD FLOW BY SPECT IMAGING-

Abstract

Introduction The mechanism of the onset of BPSD associated with Alzheimer's disease (AD) is unclear, and the incidence and frequency of these symptoms are difficult. We conducted a retrospective study on sites of decreased cerebral blood flow(CBF) during onset along with sites of increased blood flow following administration of memantine (MEM) for three BPSD parameters consisting of “agitation/irritability”, “hallucinations/delusions” and “wandering/appeal to return home” using SPECT imaging. Methods The study was targeted at 41 outpatients diagnosed with AD and presenting with BPSD (agitation/irritability: 11 cases, hallucinations/delusions: 19 cases, wandering/appeal to return home: 11 cases). Sites of decreased CBF during onset of BPSD were extracted using the statistical parametric mapping (SPM8) followed by an examination of their responsible lesions. SPECT was repeated about six months after additional administration of MEM followed by an examination of the correlation between sites of increased CBF attributable to MEM and improvement of symptoms. Results • 1 With respect to agitation/irritability, decreases in CBF were observed in the dorsolateral prefrontal cortex bilaterally, angular gyrus, right-dominant parietal association area and posterior cingulate gyrus, while increases in CBF following administration of MEM were observed in the orbital gyri bilaterally, right occipital lobe and left ventral prefrontal cortex. • 2 With respect to hallucinations/delusions, decreases in CBF were observed in the posterior cingulate gyrus, occipital lobe and lt.-dominant parietal association area, while increases in CBF following administration of MEM were observed in the parietal lobe, orbital gyrus and prefrontal cortex bilaterally. • 3 With respect to wandering/appeal to return home, decreases in CBF were observed in the mid-cerebellum, occipital lobe and parietal lobe, while increases in CBF following administration of MEM were observed in mid-cerebellum, left parietal lobe, occipital lobe, posterior cingulate gyrus, prefrontal cortex and ventral central pons. Conclusions There was suggested to be a correlation between sites of CBF following administration of MEM and improvement of BPSD.