Risk factors for dementia in Brazil: Differences by region and race

Abstract

Introduction Twelve risk factors (RFs) account for 40% of dementia cases worldwide. However, most data for population attributable fractions (PAFs) are from high‐income countries (HIC). We estimated how much these RFs account for dementia cases in Brazil, stratifying estimates by race and socioeconomic level. Methods We calculated the prevalence and communalities of 12 RFs using 9412 Brazilian Longitudinal Study of Aging participants, then stratified according to self‐reported race and country macro‐regions. Results The overall weighted PAF was 48.2%. Less education had the largest PAF (7.7%), followed by hypertension (7.6%), and hearing loss (6.8%). PAF was 49.0% and 54.0% in the richest and poorest regions, respectively. PAFs were similar among White and Black individuals (47.8% and 47.2%, respectively) but the importance of the main RF varied by race. Discussion Brazil's potential for dementia prevention is higher than in HIC. Education, hypertension, and hearing loss should be priority targets.

Education and cognitive function among older adults in Brazil and Mexico

“…Nevertheless, 68.8% of older adults in LA have low education (less than 4 years) 5 . Moreover, it is estimated that 11.0% of dementia cases in LA are attributable to low education, with this estimate reaching 13.5% in Mexico and 7.7% in Brazil 5,6 . Our study shows that even at low levels, having more education is associated with reduced odds of cognitive impairment.…”

“…4 Low education was the most important risk factor for dementia in LA, with 7.7% of dementia cases attributable to lower education in Brazil and 13.5% in Mexico. 5,6 Cognitive reserve refers to the ability of the cognitive processes to withstand brain insult with little or no loss in performance. 7 Cognitive reserve is built over the life course through dynamic processes as a consequence of exposure to education, occupation, and leisuretime activities.…”

Sex differences in dementia risk and risk factors: Individual‐participant data analysis using 21 cohorts across six continents from the COSMIC consortium

“…Nevertheless, the two Brazilian cohorts showed opposite findings, the Bambui (Brazil) Cohort Study of Ageing showed a greater risk of dementia in women, and the São Paulo Aging & Health Study cohort showed the opposite, indicating that there may be other underlying explanations for the sex difference observed in dementia risk across different populations, including within‐country variation (e.g., urban vs. rural residence, area deprivation, or race). Notably, one recent study using nationally representative data in Brazil concluded that the overall weighted population attributable fraction (PAF) of RFs for dementia was larger in poor regions than rich regions, but the overall weighted PAFs were similar between different races 41 …”

“…Notably, one recent study using nationally representative data in Brazil concluded that the overall weighted population attributable fraction (PAF) of RFs for dementia was larger in poor regions than rich regions, but the overall weighted PAFs were similar between different races. 41 F I G U R E 2 Age-and education-adjusted study-specific and pooled hazard ratios for all-cause dementia by sex (women vs. men). CI, confidence interval; HR, hazard ratio After examining by birth year, which incorporated information on age and time periods, we found the sex difference in dementia risk was largely restricted to those born before 1925.…”

Literacy, but not memory, is associated with hippocampal connectivity in illiterate adults

“…Research shows that in LMIC 48% of dementia cases could be prevented if 12 modi able dementia-risk factors were controlled (Suemoto et al, 2022). Low educational level ranks highest among these factors.…”