Bilingualism was not associated with a cognitive advantage among older Mexican adults

INTRODUCTION: We examined whether bilingualism was associated with a cognitive advantage among older urban- or rural-dwelling Mexican adults. METHODS: Participants were from the Mexican Health and Aging Study Ancillary Study on Cognitive Aging (Mex-Cog) from urban (N = 1063, 12% Spanish–English bilingual adults) and rural (N = 814, 19% Spanish–Indigenous bilingual adults) areas. Memory, language, and executive functioning were assessed. Weighted linear models stratified by locality evaluated effects of bilingualism on cognitive domains, adjusting for sociodemographic factors. RESULTS: In urban settings, Spanish–English bilingualism was not associated with cognition in any domain (all Ps > 0.05). In rural settings, Spanish–Indigenous bilingual adults had lower scores across all domains (Ps < 0.01). DISCUSSION: There was no evidence of a cognitive advantage among older bilingual adults in Mexico. Indigenous bilingual adults performed worse cognitively compared to Spanish-monolingual peers. Further work is needed to understand the linguistic and sociocultural characterization of older Mexican adults to better evaluate bilingualism and cognitive aging.