We do not have high quality data on this, but according to our own study, more than 70% of people living with dementia in Brazil do not have a diagnosis (Nakamura et al., 2015).

References:

Nakamura, A., Opaleye, D., Tani, G., & Ferri, C. P. (2015). Dementia underdiagnosis in Brazil. The Lancet, 385(9966), 418–419. https://doi.org/10.1016/S0140-6736(15)60153-2