After 1994, when the International Psychogeriatric Association (IPA) proposed the concept of behavioral and psychological symptoms of dementia (BPSD; http://www.ipa-online.org/ipaonlinev3/ipaprograms/ taskforces/bpsd/Default.asp), BPSD began to be evaluated from a variety of standpoints. In the biological treatment of BPSD, the pathological conditions must be accurately understood by clarifying the mental symptoms of demented patients and evaluating their biological background. Figure 1 shows the psychological symptoms of BPSD on the right and the behavioral symptoms on the left. One of the psychological symptoms of BPSD reported is often a depressive state, 1 but the depressive state changes as major depression enters the regressive stage or organic depression progresses to dementia, and reduced volition gradually emerges. These organic factors may underlie the ineffectiveness of antidepressants in the treatment of geriatric depression (Fig. 2).
SPECIFIC SYMPTOMS OF BPSDHirono et al. 2 compared BPSD in patients with Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD) and reported that delusions and hallucinations were notable in DLB, that disinhibition was observed at a significantly higher frequency in FTD, that apathy was noted frequently in all three groups with no significant difference between them, and that agitation, dysphoria, anxiety, euphoria, irritability, and abberant motor function were also observed in all three groups at similar frequencies. Ikeda et al.3 compared BPSD between AD and vascular dementia (VaD) and observed a generally infrequent occurrence of symptoms of BPSD in VaD except for apathy, which was observed significantly more often in VaD than in AD. Furthermore, when the details of delusions were investigated in 53 patients with AD who experienced delusions, a delusion of theft was most frequent, occuring in 75.5% of cases, followed by delusions of 'the presence of uninvited guests' or phantom boarders in 30.2% of cases, and delusions of persecution in 27.1% of cases. 4 Capgras syndrome was seen in only 1.9% of cases.