Effect of post-stroke cognitive impairment and dementia on stroke recurrence and functional outcomes: A systematic review and meta-analysis

Introduction: Post-stroke cognitive impairment (PSCI) and dementia may have a significant impact on stroke recurrence and long-term functional outcomes of patients. Aim: To investigate the potential link between PSCI and dementia, and stroke recurrence, mortality, and poor functional outcomes of stroke survivors. Methods: A systematic search across Medline, Google Scholar, and Science Direct databases was done for studies that evaluated the association of PSCI and dementia with long-term stroke outcomes. The results were expressed as pooled hazard ratios (HR) with 95% confidence intervals (CI), and heterogeneity was assessed using the I2 statistic and the Chi-square test. Subgroup analyses were performed based on the sample size, geographical location, follow-up, and type of dementia/cognitive impairment. Study quality was evaluated using the Newcastle Ottawa Scale (NOS). Results: The meta-analysis included thirteen studies. Of them, ten studies (n = 4036) reported a significant association between PSCI and stroke recurrence, with a pooled HR of 1.33 (95% CI: 1.14–1.55, I2 = 84.6%). Subgroup analysis revealed a statistically significant association between PSCI and stroke recurrence across various subrgoups. Four studies (n = 1944) demonstrated that patients with PSCI had a higher risk of poor functional outcome, with a pooled HR of 1.68 (95% CI: 1.16–2.05, I2 = 80.0%). However, the multivariate analysis did not detect a significant association between PSCI and stroke mortality, with a pooled HR of 1.50 (95% CI: 0.94–2.40, I2 = 45.9%). Conclusions: The study showed that PSCI was associated with 33% increased stroke recurrence and 68% higher rate of poor functional outcome. Our findings underscore the adverse impact of PSCI on stroke recurrence and functional outcomes, emphasizing the importance of early detection and targeted interventions to mitigate the cognitive impairment burden in stroke survivors.