Public Health.

Area of Science:

• Global Health
• Neuroscience
• Epidemiology

Background:

• Effective dementia treatments are urgently needed, especially in low- and middle-income countries (LMICs), where most dementia cases occur.
• Identifying modifiable risk factors is key to developing interventions that delay dementia onset.
• Existing research on risk factors is heavily biased towards high-income countries, creating a significant knowledge gap.

Purpose of the Study:

• To examine cross-sectional relationships between various risk factors and cognitive performance in diverse LMICs.
• To identify modifiable risk factors that are particularly suitable for targeted interventions in LMIC populations.
• To address the research inequality in dementia risk factor studies.

Main Methods:

• Utilized data from 53,136 participants across 11 countries in the Cohort Studies of Memory in an International Consortium (COSMIC).
• Investigated harmonized global cognition as the outcome, assessing numerous risk factors including age, cardiovascular health, mental health, lifestyle, and education.
• Employed linear regressions within each study and pooled results using multivariate meta-analysis.

Main Results:

• Older age, male sex, less education, anxiety, depression, stroke history, diabetes, excessive alcohol consumption, smoking, and lower physical activity were significantly associated with poorer global cognition.
• A history of angina was also linked to worse cognitive performance.
• Significant heterogeneity was observed in the relationships between risk factors and cognition across different countries.

Conclusions:

• Risk factor interventions show promise for reducing dementia prevalence in LMICs.
• The heterogeneity across countries necessitates tailoring interventions to specific regional contexts.
• Future research will utilize Machine Learning models to predict dementia incidence based on identified factors in LMICs.