Mutsuo Ijuin

Brief screening tool for mild cognitive impairment in older Japanese: Validation of the Japanese version of the Montreal Cognitive Assessment

Aim:  The Montreal Cognitive Assessment (MoCA), developed by Dr Nasreddine (Nasreddine et al. 2005), is a brief cognitive screening tool for detecting older people with mild cognitive impairment (MCI). We examined the reliability and validity of the Japanese version of the MoCA (MoCA‐J) in older Japanese subjects.

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.

Walking exercise and cognitive functions in community-dwelling older adults: preliminary results of a randomized controlled trial.

The number of epidemiological studies reporting that physical activity (e.g., walking, jogging, yoga, aerobic exercise, strength training) may reduce the risk of cognitive decline in older adults has increased recently. Among the activities, walking exercise is widely adopted as an intervention program to prevent mental decline in many municipalities. However, it is not well known whether these exercise interventions were found to have robust benefits for cognition in older adults. We conducted a pilot study of a randomized controlled trial to evaluate the effectiveness of 20-week walking exercise intervention in maintaining and/or improving cognitive function in community-dwelling older adults and to determine what types of cognitive domains are more susceptible to the intervention. Sixty-five healthy community-dwelling older individuals were randomly allocated to an exercise (N=31) or to control (N=34) groups (see Table 1). The intervention was intended to facilitate walking habits. Each exercise session was conducted once a week and consisted of 30min exercise period and 60min group walk with six to seven people. Cognitive measures were collected at baseline and after 20weeks. The following neuropsychological tests were administered to assess four different domains of cognition (attention/cognitive speed, memory, language, visuospatial function).

Necessity of normative data on the Japanese version of the Wechsler Memory Scale-Revised Logical Memory subtest for old-old people

Episodic memory is vulnerable to deterioration in people suffering from Alzheimers disease. Currently, the Logical Memory (LM) subtest of the Wechsler Memory Scale‐Revised (WMS‐R) is used internationally as an operational definition to identify people with mild cognitive impairment (MCI). However, the Japanese version of the LM has not been adequately normalized for old‐old people. Therefore, norms of the LM for people aged 75 years and over are required, and the effects of sex, age and education on performance were evaluated.

Association between polypharmacy and cognitive impairment in an elderly Japanese population residing in an urban community.

Polypharmacy is a serious medical problem among older adults. Polypharmacy can cause adverse drug reactions and is associated with frailty. Several drugs, particularly psychotropic medications, can cause cognitive impairment. Recent research also suggests that polypharmacy can cause cognitive impairment. We investigated the prevalence of polypharmacy, and examined the association between polypharmacy and cognitive impairment in a large sample of community‐dwelling older adults in Japan.

Development of the dementia assessment sheet for community-based integrated care system

A series of our studies on the development of the Dementia Assessment Sheet for Community‐based Integrated Care System 21‐items (DASC‐21) were reviewed. Study 1: to examine the distribution of scores and internal reliability of DASC‐21, trained nurses and researchers visited the homes of 1341 participants aged 65 years and older and living in the community. The nurses interviewed the participants and, when possible, their family members, to complete the DASC‐21. Then, the Mini‐Mental State Examination was carried out to select the participants of study 2. Study 2: to examine the concurrent and discriminant validity, experienced psychiatrists and psychologists, who were blind to the findings of study 1, visited the homes of 131 subjects who were selected from the participants of study 1 and completed the Clinical Dementia Rating (CDR), the Mini‐Mental State Examination and the Frontal Assessment Battery (FAB). Cronbachs coefficient alpha of the DASC‐21 was 0.808–0.950. Scores of the DASC‐21 significantly correlated with CDR total and box scores, Mini‐Mental State Examination and Frontal Assessment Battery. In an analysis of variance, CDR had the main effect on the score of the DASC‐21. Receiver operating characteristic analysis showed that the DASC‐21 had sufficient discriminatory ability between dementia (CDR1+) and non‐dementia (CDR0 or CDR0.5; area under the curve = 0.804–0.895). When using a cut‐off point of 30/31, sensitivity was 83.3–94.1% and specificity was 77.3–86.4%. The DASC‐21 has sufficient reliability and validity as a tool to evaluate impairments in daily functioning and in cognitive functions, to detect dementia, and to assess the severity of dementia in the community. Geriatr Gerontol Int 2016; 16 (Suppl. 1): 123–131.

Reliability and validity of A Quick Test of Cognitive Speed for detecting early-stage dementia in elderly Japanese

Aim:  The aim of this study was to evaluate the reliability and validity of A Quick Test of Cognitive Speed (AQT) for detecting early‐stage dementia in the elderly Japanese population.

Distribution of Mini-Mental State Examination scores among urban community-dwelling older adults in Japan.

The Mini‐Mental State Examination (MMSE) is widely used as a cognitive screening test for older adults; however, cognitive performance can be affected by age, education, and sample selection bias, including time and place. The aims of this study were to examine the distribution of scores on the Japanese version of the MMSE in an urban community sample and to provide normative data for older Japanese adults.