Bilingualism and Age of Acquisition in Alzheimer Disease: a 18F-FDG PET Study (P3.173)

Objective: To investigate the impact of bilingualism and ageof acquisitionof the second language (L2) on cognitive and brain reserve (CR) in patients with Alzheimer’s disease (AD). Background: Bilingualism is an important factor influencing CR, as education and an active lifestyle. However, the relationship between bilingualism and functional cerebral modifications in neurocognitive disorders has rarely been studied and remains controversial. Design/Methods: We included in our observational retrospective monocentric study all patients with a clinical diagnosis of probable AD, who underwent 18F-FDG PET scan and for which the information of the number of language spoken, ageof acquisitionand level of usage for L2 was available. Our population consisted of 41 subjects, 16 monolinguals and 25 bilinguals. We used SPM12 group analysis design to directly compare voxelwise the glucose metabolism of both groups, correcting for age, gender, MMSE scores, years of formal education (p Results: Monolingual and bilingual patients did not differ in sociodemographic variables (age, gender, MMSE, years of education). Bilinguals showed lower metabolism compared to monolinguals in several key regions associated with conflict monitoring, planning and language, including the anterior cingulum, the mesial frontal cortex and the insula, bilaterally, and the right hippocampus. The opposite comparison showed no suprathreshold cluster. Conclusions: According to the brain reserve hypothesis, these results suggest that bilingualism plays an important role in CR, compensating for AD advancing disease, namely in key regions associated with conflict monitoring and planning. Learning and practicing a second language along life could be a protective factor against the adverse effects of neurodegeneration. Disclosure: Dr. Epiney has nothingto disclose. Dr. van Assche has nothingto disclose. Dr. Frasca Polara has nothingto disclose. Dr. Daniela has nothingto disclose. Dr. Assal has nothingto disclose. Dr. Garibotto has nothingto disclose.