Kenjiro Komori

Increased prevalence of vascular dementia in Japan A community-based epidemiological study

Background and Objective: It has been suggested that there is a major difference in the ratio of AD to vascular dementia (VaD) between Japan and Western countries. To determine the type-specific prevalence of dementia in community-dwelling elderly from the Japanese community of Nakayama, all patients with dementing illness underwent a CT scan. Methods: A door-to-door three-phase population survey was carried out on all persons aged 65 years and older residing at home on the prevalence day (January 1, 1997). The ascertainment of cases was made between January 1997 and March 1998. The study included a psychiatric interview; physical, neurologic, and neuropsychologic examinations; comprehensive laboratory tests; and cranial CT. A public health nurse also interviewed a person close to each subject. Dementia was defined according to the Diagnostic and Statistical Manual of Mental Disorders, third edition–revised, criteria, AD according to the National Institute of Neurological and Communicative Disorders and Stroke–Alzheimer’s Disease and Related Disorders Association, and VaD according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition, combined with information from the patient’s neurologic history and CT scanning. Results: Of 1438 inhabitants, 1162 (81.0%) completed the protocol. The prevalence of dementia was 4.8%. Of the 60 subjects with dementia, 35% had AD, 47% had VaD, and 17% had dementia resulting from other causes. Conclusions: The prevalence of dementia was similar to previous reports, but, contrary to results of virtually all studies conducted in developed countries and those recently conducted in Japan, almost half of the cases in the present study appeared to have VaD with neuroradiologic confirmation.

The Stereotypy Rating Inventory for frontotemporal lobar degeneration

A many behavioral disturbances, Stereotypic behaviors are among the best discriminators of Frontotemporal Lobar Degeneration (FTLD). A recent preliminary report suggests many of the behavioral symptoms, including stereotypic behaviors in FTLD patients, respond to medication with selective serotonin re-uptake inhibitors. However, there is no scale that evaluates stereotypic behaviors comprehensively. To assess the wide range of stereotypic behaviors encountered in FTLD, we developed a new instrument, the Stereotypy Rating Inventory (SRI). The SRI assesses five distinctive stereotypic behavioral disturbances often seen in patients with FTLD: eating and cooking behaviors, roaming, speaking, movements, and daily rhythm. The SRI uses the same technique as the Neuropsychiatric Inventory (NPI) in that both the frequency and the severity of each behavior are determined. The studies reported here demonstrate the content and concurrent validity, as well as inter-rater and test-retest reliability, of the instrument. Scores of FTLD patients (n=26) on the SRI were much higher than those of patients with Alzheimers disease (n=46), patients with vascular dementia (n=26), and normal control subjects (n=40). The SRI appears to be a useful instrument for detecting stereotypic behaviors and monitoring of therapies in FTLD patients.

Frequency and Clinical Characteristics of Early-Onset Dementia in Consecutive Patients in a Memory Clinic

Aims: To investigate the frequency, rate of causes of dementia, and clinical characteristics of early-onset dementia in consecutive patients of a memory clinic. Methods: A total of 668 consecutive demented patients were involved in this study. We examined the distribution of patients’ diagnosis, differences in sex, education, dementia severity and cognitive function at the first visit, and the duration from onset to consultation. We also examined the changes in the proportion of subjects during the research period. Results: There were 185 early-onset patients, 28% of all demented patients. No significant differences were observed between the early-onset and late-onset dementia groups in Clinical Dementia Rating and Mini-Mental State Examination score at the first consultation, but the duration from onset to consultation was significantly longer in the early-onset group. In the early-onset group, the rates of patients with Alzheimer’s disease and dementia with Lewy bodies were relatively low and the rate of patients with frontotemporal lobar degeneration was relatively high. There were no significant differences in the proportion between either demented subjects and nondemented subjects or early-onset dementia patients and late-onset dementia patients during the research period. Conclusion: We conclude that early-onset dementia is not rare and its clinical characteristics and causes are different from late-onset dementia.

Efficacy of fluvoxamine as a treatment for behavioral symptoms in frontotemporal lobar degeneration patients

Patients with frontotemporal lobar degeneration (FTLD) present a profound personality change, social misconduct, overeating, and stereotyped behavior. We examined the hypothesis that many of the behavioral symptoms of FTLD will respond to selective serotonin reuptake inhibitors (SSRIs). Sixteen FTLD patients were treated with an SSRI (fluvoxamine maleate) in an open 12-week trial. Treatment responses for stereotyped behavior and other neurobehavioral symptoms were evaluated by the Stereotypy Rating Inventory and the Neuropsychiatric Inventory. The behavioral symptoms, especially stereotyped behaviors of FTLD, significantly improved after treatment. Randomized, placebo- and other SSRI-controlled trials may improve available treatments.

Interrater reliability of the Physical Self-Maintenance Scale and the Instrumental Activities of Daily Living Scale in a variety of health professional representatives

This study was performed to assess interrater reliability of the Japanese version of the Physical Self-Maintenance Scale (PSMS) and the Instrumental Activities of Daily Living Scale (IADL), which are simple and efficient assessment instruments of functional abilities in elderly patients. The subjects were 25 consecutive patients with Alzheimers disease who were outpatients of the Department of Neuropsychiatry in Ehime University School of Medicine and their principal caregivers. One neuropsychiatrist administered the PSMS and IADL, and all sessions were videotaped. Then one clinical psychologist, one public health nurse and one neurologist, and one occupational therapist from another institution, viewed the videotape and performed reassessments. All interrater reliabilities between the neuropsychiatrist and the neurologist, the public health nurse, the clinical psychologist and the occupational therapist were extremely good. Interrater reliability between the public health nurse and the clinical psychologist, between the clinical psychologist and the neurologist and between the public health nurse and the neurologist was also extremely good. The PSMS and IADL showed good interrater reliability between personnel from different disciplines. They are likely to be useful tests for everyday medical consultations and for field research.

The Validity of the MMSE and SMQ as Screening Tests for Dementia in the Elderly General Population – A Study of One Rural Community in Japan

Objective: To compare the validity of the Mini Mental State Examination (MMSE) and the Short-Memory Questionnaire (SMQ) as screening tests to detect dementia in the elderly general population. Subjects: Six hundred and sixty-two subjects and their informants from the elderly general population sample who had completed these tests. Setting: One rural community survey in Japan. Method: We used receiver-operating characteristic analysis to compare the performance of the MMSE and the SMQ with the clinical diagnosis of dementia according to DSM-III-R. Results: The areas under the receiver-operating characteristic curve of the MMSE and the SMQ were 0.980 (SE = 0.006) and 0.982 (SE = 0.008), respectively. This differed from chance to a highly significant degree for both the MMSE and the SMQ, but the difference between the two scales was not statistically significant. Conclusion: As screening tests to detect dementia in the elderly general population, the SMQ which is assessed by informants demonstrates a statistically significant discriminating ability as well as the MMSE.

Alteration of rCBF in Alzheimer's disease patients with delusions of theft

We investigated the neural substrate of the delusion of theft in patients with Alzheimers disease (AD). Nine AD patients with only one type of delusion (delusions of theft) and nine age, cognitive function-matched AD patients without any type of delusions were selected from 334 consecutive outpatients of Ehime University Hospital. All subjects underwent 99mTc-HMPAO SPECT scanning, and SPECT images were analyzed by Statistical Parametric Mapping (SPM). AD patients with delusions of theft showed significant hypoperfusion in the right medial posterior parietal region compared to patients without delusions. Our data suggest that attention impairment or lack of awareness of illness caused by right parietal dysfunction might play a role in producing the delusion of theft.

Surface dyslexia in a Japanese patient with semantic dementia: evidence for similarity-based orthography-to-phonology translation.

We studied the reading performance of a Japanese-speaking patient, TI, with bilateral but asymmetrical (left more than right) temporal-lobe atrophy, severe anomia, and poor word comprehension. Most Japanese kanji characters correspond to several different legitimate pronunciations in different contexts, with varying degrees of correspondence consistency. TI made many errors in reading aloud words that violate statistically typical character-sound correspondences, especially for less common words, but had relatively preserved ability to read aloud strings in which the assignment of the typical pronunciation for each component character yields the correct pronunciation for the whole word. The degree of consistency of character-sound correspondences affected his performance on both words and nonwords in a graded manner. One interpretation is that TIs surface dyslexic reading reflects intact direct computation of phonology from orthography, but without the additional constraint from word meaning that is, in this framework, considered critical for correct pronunciation of lower-frequency words with atypical character-sound correspondences. Another interpretation is that TIs performance reflects partially damaged lexical knowledge of whole-word orthography and phonology, coupled with spared sublexcal knowledge of character-sound correspondence rules. Whichever of these interpretations is preferred, this study offers the most detailed information yet available on the characteristics of surface dyslexia in Japanese.

Cognitive function and psychiatric symptoms in early- and late-onset frontotemporal dementia.

Background/Aim: Some recent studies mentioned that late-onset frontotemporal dementia (FTD) is more common than previously assumed. Although much research has been done in the field, there are no systematic studies which have compared clinical characteristics of early- and late-onset FTD. The aim of this study was to compare cognitive function and psychiatric symptoms in patients with early- and late-onset FTD. Methods: Study participants were consecutive outpatients. There were 35 FTD patients; their mean age at onset was 63.0 years. We studied sex, education, duration from onset to consultation, Clinical Dementia Rating (CDR) scores, Mini-Mental State Examination (MMSE) scores, Raven’s Coloured Progressive Matrices (RCPM) scores, and Neuropsychiatric Inventory (NPI) scores at first consultation of early- and late-onset FTD patients. Results: There were no significant differences in sex ratio, education, CDR scores, and duration from onset to consultation. There were significant differences in the total MMSE scores, ‘three-word recall task’, ‘construction task’, and RCPM scores; late-onset groups scored significantly lower than early-onset groups. There were significant differences in the apathy domain of NPI and total NPI scores; late-onset groups scored significantly higher than early-onset groups. Conclusion: Late-onset FTD patients may have memory and visuospatial deficits in addition to their behavioural changes, even if they are clinically diagnosed according to consensus diagnostic criteria. They also present more apathy, and they may have a different histolopathological background.

Frontotemporal Lobar Degeneration: A Study in Japan

Frontotemporal lobar degeneration is the most common form of cortical dementia occurring in the presenium after Alzheimer’s disease. We analyzed two types of frontotemporal dementia (FTD) and semantic dementia (SD) selected from a consecutive series of outpatients based on neuropsychological symptoms, psychiatric symptoms and abnormal behavior. In our series of 134 patients with primary degenerative dementia, there were 16 cases of FTD and 6 cases of SD. Patients with subgroups of FTD and patients with SD were distinguishable only by the presence of aphasia in the latter group. They were not distinguishable from one another by other neuropsychological examinations, behavioral abnormalities or psychiatric symptoms assessed with the Neuropsychiatric Inventory.