Matsuda Osamu

Aim: This study examined the significance of age-related subtest scores from the Japanese version of the Wechsler Adult Intelligence Scale-III in patients in the early stages of Alzheimer's disease (AD). Methods: The subjects of this study included 58 elderly Japanese persons classified into two groups: AD group (n = 29) and control group (n = 29). These groups did not differ in age, years of education, gender ratio, Hasegawa's Dementia Scale-Revised score, or Full-Scale IQ score. No subject scored below the cut-off point on Hasegawa's Dementia Scale-Revised, a frequently used dementia screen test in Japan. Results: At the index score level, General Ability Index scores were the only scores that differed significantly between the groups, with the AD group scoring significantly lower than the control group (P < 0.05, Hedges' g = 0.54). At the subtest level, information scores were the only scores that differed significantly between the groups, with the AD group significantly lower than the control group (P < 0.01, Hedges' g = 0.74). Conclusion: The General Ability Index is a composite score that deducts components of working memory and processing speed, which are sensitive to decline with normal ageing, from the Full-Scale IQ. It also served as a subtest measuring crystallized intelligence, especially of acquired knowledge of general and factual information. Therefore, the results of this study seem to suggest that Wechsler Adult Intelligence Scale-III profile of very early AD may be characterized by weak performance on subtests normally resistant to decline with ageing.

Background: Acetylcholinesterase inhibitors (i.e. donepezil) are known to benefit Alzheimer's disease (AD) patients. However, the combined effects of acetylcholinesterase and cognitive stimulation therapy (CST) are still debated. The present study examined their combined effects on the progression of cognitive decline in AD. Methods: The present study was a non-randomized controlled study and included two groups of patients with AD (i.e. CST group and control group). The CST group consisted of 31 patients with AD who received donepezil and weekly, 30-min CST sessions over the course of 7 weeks. The control group consisted of 18 patients who received only donepezil. Changes in cognitive abilities were assessed with Hasegawa's Dementia Scale-Revised (HDS-R) and were statistically analyzed by repeated-measure analysis of variance (anova). Results: ANOVA showed a significant group x time interaction effect on the HDS-R score. HDS-R scores for the CST group increased significantly during the intervention period, whereas the scores for the control group did not increase. Differences between the means of pre- and post-test HDS-R scores were significantly different between the groups; scores were significantly higher for the CST group than the control group. The groups differed significantly in the proportion of subjects whose score increased by more than four points on the HDS-R (Fisher's exact test, P < 0.05; 8 patients (25.8%) in the CST group and none (0.0%) in the control group). Conclusions: These results suggest that CST is one of the important non-pharmacological treatment strategies for patients with AD.

Background: Little is known about how cognitive domains other than episodic memory are affected during the mild cognitive impairment (MCI) stage of Alzheimer's disease (AD). We attempted to clarify this issue in this study. Methods: Fifty-seven Japanese subjects were divided into two groups: one comprising people in the MCI stage of AD (MCI group, n = 28) and the other of normal controls (NC group, n = 29). Cognitive functions were assessed using the Japanese version of the neurobehavioral cognitive status examination (J-COGNISTAT). Results: The MCI group performed significantly worse than the NC group on subtests that assessed orientation, confrontational naming, constructive ability, episodic memory, and abstract thinking. Three-quarters of the MCI group had deficits in memory and other non-mnemonic domains, particularly constructive ability and abstract thinking. However, within-subject comparisons showed that the MCI group performed significantly worse on the memory subtest compared to any other subtest. Conclusions: Besides episodic memory, multiple non-mnemonic cognitive domains, such as constructive ability and abstract thinking, are also impaired during the MCI stage of AD; however, these non-mnemonic deficits are smaller than episodic memory impairment.