Dementia and cognitive decline in Black Brazilians: a narrative review.

Abstract

Background: Dementia prevalence is projected to rise most sharply in low-and middle-income countries, including Brazil. The Brazilian Black population (including individuals identified as Black and Brown) represents 56.5% of the population and is expected to comprise most older adults in the coming decades.

Aims: This narrative review aims to synthesize studies on dementia, cognitive decline, and cognitive aging among Black Brazilians, analyzing publication characteristics and key findings to identify knowledge gaps and propose directions for future research.

Methods: We searched PubMed, LILACS, and SciELO databases, and the SciSpace AI-powered tool. Eligible studies included those that: (a) examined the Brazilian Black population; and (b) provided descriptions or analyses of characteristics, clinical manifestations, risk factors, or responses to interventions related to cognitive decline, cognitive aging, and dementia. Publications that were not full-length articles were excluded.

Results: We identified 18 papers (2000-2025), mostly cross-sectional, published in international journals. The median proportion of Black participants among samples was 39.5%. Seven studies were conducted in the state of São Paulo, and ten were carried out in the Southeast region of Brazil. A recurring sociodemographic feature in nine studies was the low educational attainment among Black participants. Twelve studies identified modifiable risk factors for dementia among black individuals, mainly related to socioeconomic disadvantages. Cognitive performance was assessed using various standardized instruments, such as the Mini-Mental State Examination and Clinical Dementia Rating Scale. We did not find studies about dementia care or any clinical trials.

Conclusion: Our findings indicate the underrepresentation of Black individuals in dementia research. Ensuring the inclusion of Black populations in research requires investment in recruiting Black professionals into research teams, conducting interventions, and developing partnerships within Black communities. Existing Brazilian evidence suggests socioeconomic factors exert greater influence on cognitive function than genetic factors, underscoring the need for public policies that address social, income, healthcare access, and educational inequities. Beyond social investments, local research should develop culturally appropriate cognitive assessment tools and culturally compatible protective activities and lifestyles among marginalized populations. Finally, culturally tailored strategies for person-centered dementia care and carers' support are needed.