Top cited papers in International Psychogeriatrics: 6b. Behavioral disorders and caregivers' reaction in Taiwanese patients with Alzheimer's disease.

The behavioral and psychological symptoms of dementia (BPSD) are common and serious problems that affect the quality of life of the patients who experience such symptoms as well as their caregivers (Matsui et al., 2006). BPSD present a major challenge in the medical management of cognitively impaired patients. Our paper entitled “Behavioral disorders and caregivers’ reaction in Taiwanese patients with Alzheimer’s disease” (hereafter referred to as the “paper”) (Fuh et al., 2001) has been cited widely, reflecting the importance of these clinical issues and the growing international interest in studies of BPSD. A valid and reliable evaluating instrument is essential to detect and study BPSD. The aims of the paper were to evaluate the applicability of the Chinese (Taiwanese) version of the Neuropsychiatric Inventory (NPI) (Cummings et al., 1994), and to explore the neuropsychiatric manifestations of Taiwanese patients with Alzheimer’s disease (AD) and the associated caregiver distress (Fuh et al., 2001). The NPI was developed to assess psychopathology in dementia patients and is one of the most commonly used instruments to evaluate BPSD. It evaluates 10 neuropsychiatric disturbances often observed in dementia: delusions, hallucinations, agitation, dysphoria, anxiety, apathy, irritability, euphoria, disinhibition and aberrant motor behavior. The night-time behavior disturbances and appetite and eating abnormalities were added to the NPI later (NPI-12) (Cummings, 1997). A nursing home version also was developed for use by professional caregivers within institutions (Wood et al., 2000). The severity and frequency of each neuropsychiatric symptom are rated on the basis of scripted questions administered to the patient’s caregiver. The NPI also assesses caregiver distress engendered by each of the neuropsychiatric disorders. The NPI provides a clear and simple description of each symptom and assists researchers and clinicians to better define each symptom of BPSD. The high cross-cultural reliability of the NPI is based on its highly structured format and scripted questions. We have reviewed the 32 articles that cited our paper and discovered that 18 of them (56.2%) found the paper of interest because it provided evidence of the existence of neuropsychiatric sub-syndromes in dementia. Six articles (18.9%) cited the paper because of cross-cultural comparisons of BPSD, a growing area of interest in dementia and BPSD research. BPSD refers to a heterogeneous range of psychological reactions, psychiatric symptoms, and behaviors occurring in people with dementia. Factor analysis techniques have been used to explore behavioral dimensions that may comprise BPSD. Table 1 summarizes studies using factor analytic techniques to identify the subsyndromes contained within the NPI (Frisoni et al., 1999; Fuh et al., 2001; Aalten et al., 2003; Lange et al., 2004; Mirakhur et al., 2004; Borroni et al., 2006; Hollingworth et al., 2006; Matsui et al., 2006; Aalten et al., 2007; Zuidema et al., 2007). Three to five sub-syndromes were found in these studies and different terms were used to label them. Despite some differences among these studies, the associations of the following symptoms were very consistent: (1) depression and anxiety, (2) delusions and symptoms of hallucination, (3) agitation and irritability, (4) disinhibition and euphoria. The symptoms were in the same subsyndrome in most of the reviewed studies and across various cultural settings, suggesting that these four common sub-syndromes may reflect four distinctive pathophysiological disorders (Robert et al., 2005). More studies are needed to determine if these four sub-syndromes also share treatment-related characteristics. Apathy and aberrant motor activities are two symptoms that had variable associations with other individual symptoms in different patient populations. Apathy was associated with depression in some studies (Aalten et al., 2003; 2007; Hollingworth et al., 2006), with aberrant motor activities in others (Frisoni et al., 1999; Lange et al., 2004; Mirakhur et al., 2004; Matsui et al., 2006; Zuidema et al., 2007), or with other symptoms in some studies (Fuh et al., 2001; Borroni et al., 2006; Zuidema et al., 2007). The relationship between depression and apathy is controversial. It is recognized that apathy overlaps with depression, which is not surprising considering that common symptoms of both syndromes include diminished motivation and interest as well as lack of insight. The major difference is that apathy may occur in the absence of depressed mood. One study showed that