Speaking one more language in early life has only minor effects on cognition in Taiwanese with low education level: the Taishan Project.

BACKGROUND: Increasing evidence shows that bilingualism or multilingualism may have beneficial effects on preventing dementia. We performed a cross-sectional, community-based study in Taiwan. Some elders (older than 70 years) in Taiwan can speak Japanese because of the formal Japanese education they received before World War II, when Taiwan was under Japanese rule. After the war, Mandarin Chinese was adopted as the official language of Taiwan. We assessed whether constantly using three languages had an effect on dementia prevalence and cognitive function. METHODS: We defined multilingualism as the ability to fluently speak Taiwanese (T), Japanese (J), and Mandarin Chinese (C) in daily life. We evaluated the Mini-Mental State Examination and AD8 questionnaire results of 514 community-dwelling people older than 70 years in Taishan, Taiwan. RESULTS: Seventy-three of the subjects (14.2%) were multilingual (T, J, C) and 441 (85.8%) were bilingual (T, C). No difference was noted in dementia prevalence between multilingual (6.8%) and bilingual (7.4%) populations, but multilinguals were older than bilinguals (mean age: 79.9 vs 77.3 years). Multilinguals had higher Mini-Mental State Examination scores than bilinguals (mean: 24.6 vs. 22.7). However, after the subjects were stratified into low and high education level groups, the Mini-Mental State Examination difference was found to be significant in only the low education level group. CONCLUSIONS: Dementia prevalence did not significantly differ between the multilingual (T, J, C) and bilingual (T, C) groups. However, given that the average age of the multilingual group was approximately 2 years older than that of the bilingual group, there may have been minor effects in the multilingual group.

More Delusions May Be Observed in Low-Proficient Multilingual Alzheimer's Disease Patients.

BACKGROUND: Language impairment and behavioral symptoms are both common phenomena in dementia patients. In this study, we investigated the behavioral symptoms in dementia patients with different language backgrounds. Through this, we aimed to propose a possible connection between language and delusion. METHODS: We recruited 21 patients with Alzheimer's disease (AD), according to the DSM-IV and NINCDS-ADRDA criteria, from the memory clinic of the Cardinal Tien Hospital in Taipei, Taiwan. They were classified into two groups: 11 multilinguals who could speak Japanese, Taiwanese and Mandarin Chinese, and 10 bilinguals who only spoke Taiwanese and Mandarin Chinese. There were no differences between age, education, disease duration, disease severity, environment and medical care between these two groups. Comprehensive neuropsychological examinations, including Clinical Dementia Rating (CDR), Mini-Mental Status Examination (MMSE), Cognitive Abilities Screening Instrument (CASI), Verbal fluency, Chinese version of the Boston naming test (BNT) and the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD), were administered. RESULTS: The multilingual group showed worse results on the Boston naming test. Other neuropsychological tests, including the MMSE, CASI and Verbal fluency, were not significantly different. More delusions were noted in the multilingual group. Three pairs of subjects were identified for further examination of their differences. These three cases presented the typical scenario of how language misunderstanding may cause delusions in multilingual dementia patients. Consequently, more emotion and distorted ideas may be induced in the multilinguals compared with the MMSE-matched controls. CONCLUSION: Inappropriate mixing of language or conflict between cognition and emotion may cause more delusions in these multilingual patients. This reminds us that delusion is not a pure biological outcome of brain degeneration. Although the cognitive performance was not significantly different between our groups, language may still affect their delusion.