Comparison of behavioral and psychological symptoms in early-onset and late-onset Alzheimer’s disease Yasutaka Toyota 1 , Manabu Ikeda 1,2 * , Shunichiro Shinagawa 1,3 , Teruhisa Matsumoto 1 , Naomi Matsumoto 1 , Kazuhiko Hokoishi 1 , Ryuji Fukuhara 1 , Tomohisa Ishikawa 1 , Takaaki Mori 1 , Hiroyoshi Adachi 1,4 , Kenjiro Komori 1 and Hirotaka Tanabe 1 1 Department of Neuropsychiatry, Neuroscience, Ehime University Graduate School of Medicine, Ehime, Japan 2 Department of Psychiatry and Neuropathobiology, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan 3 Department of Psychiatry, Jikei University School of Medicine, Tokyo, Japan 4 Osaka University Health Care Center, Osaka, Japan SUMMARY Background When comparing with early-onset Alzheimer’s disease (EO-AD) and late-onset Alzheimer’s disease (LO-AD), some symptomatological differences in clinical features can be seen between them. Rapid progression, more severe language problems or visuospatial dysfunction occur more often in EO-AD patients. However, there have been very few reports about the differences in behavioral and psychological symptoms between these two groups. Aim The aim of this study was to demonstrate the differences in behavioral symptoms between EO-AD and LO-AD groups. Method Three hundred and seven consecutive outpatients with AD were put into an EO-AD group (46 patients) or a LO-AD group (261 patients). Comprehensive assessment batteries, including the Neuropsychiatric Inventory (NPI), were administered at the first medical assessment. Results Significant differences were found between the EO-AD and LO-AD groups in terms of NPI total score (EO-AD: 10.3  10.9, LO-AD: 17.8  17.0, p ¼ 0.004) and number of patients who experienced each NPI subscale score (delusion; EO-AD: 13.0%, LO-AD: 50.6%, p < 0.001). There were no differences in cognitive functions or dementia severity between two groups. Conclusion In EO-AD, behavioral and psychological symptoms are relatively fewer than LO-AD at the first medical assessment. Copyright # 2007 John Wiley & Sons, Ltd. key words — early-onset; Alzheimer’s disease; Neuropsychiatric Inventry (NPI); behavioral and psychological symptoms of dementia (BPSD); outpatients INTRODUCTION In recent years, reports based on large clinicopatho- logic studies have shown that the pathologies of Alzheimer’s presenile dementia and senile dementia of Alzheimer type are not qualitatively different (Newton, 1948; Neumann and Cohn, 1953; Corsellis, 1962). However, when comparing their clinical symptoms in detail, several differences can be found (Chui et al., 1985; Mayeux et al., 1985). Some studies have reported that rapid progression (Jacobs et al., 1994), language problems (Imamura et al., 1998) or visuospatial dysfunction (Fujimori et al., 1998) occur more often in early-onset Alzheimer’s disease (EO-AD) patients. There have been very few reports about the differences of behavioral and psychological symptoms of dementia (BPSD) between EO-AD and late-onset Alzheimer’s disease (LO-AD) groups. Ferran et al. (1996) reported that in EO-AD patients, delusions, INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY Int. J. Geriatr. Psychiatry 2007; 22: 896–901. Published online 8 March 2007 in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/gps.1760 *Correspondence to: M. Ikeda, Department of Neuropsychiatry, Neuroscience, Ehime University Graduate School of Medicine, Ehime, Japan. E-mail: mikeda@m.ehime-u.ac.jp Copyright # 2007 John Wiley & Sons, Ltd. Received 27 September 2006 Accepted 28 November 2006