Cardiovascular disease as a predictor of dementia: a cross-national ecological study of 204 countries

Background and Aims: Cardiovascular disease (CVD) and dementia represent two of the most pressing global health challenges, particularly in low- and middle-income countries (LMICs). While vascular pathology is increasingly recognized as a contributor to cognitive decline, few studies have systematically explored the global association between CVD and dementia using standardized, population-level data. This study aimed to investigate the relationship between CVD and dementia incidence across 204 countries, stratified by economic status, development level, and geographic region. Methods: Age-standardized incidence rates for cardiovascular disease (CVD) and dementia in 2021 were sourced from the Global Burden of Disease Study. To examine global and regional associations, bivariate analyses (Pearson and Spearman correlations) and partial correlations were conducted, adjusting for ageing, economic affluence, genetic predisposition, and urbanization. Linear and multivariate stepwise regression models were applied to estimate the extent to which CVD incidence contributes to dementia incidence at the population level. Results: Globally, CVD incidence was significantly associated with dementia incidence (Pearson r = 0.777; Spearman ρ = 0.868; p < 0.001). CVD explained approximately 43.0% of the variance in dementia incidence at the population level (r² = 0.4303), even after adjusting for key confounders. The association was notably stronger in low- and middle-income countries (LMICs) and developing regions. Among CVD subtypes, peripheral arterial disease (β = 0.903), cardiomyopathy (β = 0.869), and atrial fibrillation (β = 0.708) demonstrated the strongest independent associations with dementia incidence. Conversely, rheumatic heart disease exhibited a negative association. Conclusion: This study demonstrates a robust population-level association between CVD and dementia across global settings, particularly in resource-limited regions. Findings underscore the importance of integrated public health approaches targeting shared vascular risk factors. Given the ecological design, further individual-level, longitudinal research is needed to clarify causal pathways and inform targeted interventions.