The study found a higher prevalence of dementia and MCI in monolinguals compared to bilinguals in an older urban community. Bilinguals displayed better cognitive functioning regardless of age, sex, education, socioeconomic and occupational status.

Bilingualism's cognitive benefits may stem from increased neuronal plasticity and cognitive reserve from multilingual practice. The study used high-quality, culturally adapted cognitive tests and accounted for potential confounding factors in its methodology.

Results showed a significantly lower prevalence of dementia (0.4%) and MCI (5.3%) in bilinguals compared to monolinguals (4.9% and 8.5%, respectively), irrespective of education level.