The association of English‐Spanish and Indigenous‐Spanish bilingualism with cognition among older adults in the Mexican Health and Aging Study (MHAS)

Abstract

AbstractBackgroundWhile several studies have reported a “bilingual advantage” in cognition among older adults, others have not. Most studies of bilingualism and cognitive aging are in urban settings among high income countries, limiting the generalizability among bilinguals residing in lower‐and middle‐income countries, such as Mexico. Additionally, the association of bilingualism and cognition among indigenous populations is unknown. In Mexico, there are almost 7 million speakers of indigenous languages, residing primarily in rural areas, and over 15 million people that report speaking English, predominantly in urban settings. To account for sociocultural factors confounding the type of bilingualism (i.e., English‐Spanish, Indigenous‐Spanish), we evaluated whether bilingualism was associated with better cognitive functioning among adults across urban and rural regions in Mexico.MethodAnalyses included participants from the Mexican Health and Aging Study (MHAS) aged 55 and older in urban (N = 1053, 12% Spanish‐English bilinguals) and rural (N = 814, 20% Spanish‐Indigenous bilinguals) areas. Participants reported speaking English and/or an indigenous language in addition to Spanish. Participants completed comprehensive cognitive testing assessing memory, language, executive function, and visuospatial domains. General linear models stratified by region evaluated bilingualism on cognitive domain performance covarying for sociodemographic factors.ResultSociodemographic characteristics differed by region and language group. English‐Spanish bilinguals in urban areas were younger, predominantly men, with higher education, less likely illiterate, and with greater U.S. migration history compared to monolinguals. In rural areas, Indigenous‐Spanish bilinguals were younger, with less education, higher prevalence of illiteracy, and less likely to have U.S. migration history compared to monolinguals. In urban settings, English‐Spanish bilingualism was not associated with performance on any cognitive domain (p>0.05). In rural settings, Indigenous‐Spanish bilingualism was associated with worse performance across all cognitive domains (p<0.01).ConclusionThere was no evidence of a bilingual cognitive advantage among older adults residing in urban and rural regions in Mexico. While indigenous bilinguals demonstrated the lowest cognitive test performance, further work is required to understand the socioeconomic and environmental factors associated with bilingualism among indigenous populations in Mexico. Greater characterization of their bilingualism (i.e., age and context of acquisition, proficiency, frequency of use) across all languages can help elucidate the association between bilingualism and cognitive test performance.