Abstract
Introduction: This study investigated whether cardiovascular diseases (CVD), hypertension, and stroke contribute to the risk of developing mild cognitive impairment (MCI) in older adults living with diabetes.
Methods: Studies examining the association of CVD, hypertension, and stroke with MCI were systematically searched in PubMed, Web of Science, Scopus, and Embase for articles published up to 2025 in English or Persian. After duplicate removal, studies were screened against predetermined inclusion and exclusion criteria. Data were analyzed using Comprehensive Meta-Analysis software (Version 2). Publication bias was evaluated using Egger’s test, and heterogeneity was assessed via the I² statistic. Pooled effect sizes were reported as odds ratios (ORs) with 95% confidence intervals (CIs).
Results: Twenty studies from 10 countries, encompassing 36,094 participants, met the eligibility criteria. Depending on heterogeneity, either a fixed-effects model (I²<50%) or a random-effects model (I²>50%) was applied. In univariate analyses, CVD (OR=1.485; 95% CI: 1.106–1.993; I²=89.37%), hypertension (OR=1.474; 95% CI: 1.273–1.707; I²=38.24%), and stroke (OR=1.592; 95% CI: 1.290–1.965; I²=69.88%) were each significantly associated with an increased likelihood of cognitive impairment. However, after adjusting for clinically relevant confounders identified from previous research and available study-level data, only the association between stroke and MCI remained statistically significant (OR=1.711; 95% CI: 1.305–2.244; I²=32.54%), whereas the associations with CVD and hypertension weakened and were no longer significant.
Conclusion: These findings indicate that among older adults with diabetes, hypertension and stroke are linked to a higher risk of MCI. However, the observed associations for CVD and hypertension diminish when potential confounding factors are considered, suggesting that shared underlying mechanisms may account for these relationships. Although causal inferences are limited by the observational nature of the included studies, maintaining healthy blood pressure and cardiovascular risk factors remains essential for supporting cognitive health. Further longitudinal and interventional studies are needed to clarify causal pathways and guide future prevention strategies.