Uric Acid and Cognitive Impairment in Patients with Acute Ischemic Stroke: A Meta-Analysis.

Serum uric acid (UA) has been suggested to be correlated with outcomes after stroke. We performed a meta-analysis to evaluate the association between serum UA and post-stroke cognitive impairment (PSCI) in patients with acute ischemic stroke (AIS). Relevant observational studies were identified by search of electronic databases including PubMed, Embase, and Web of Science. A randomized-effect model incorporating the possible between-study heterogeneity was used to pool the results. Overall, eleven studies with 4246 patients of AIS were included, 2073 (48.8%) of them had PSCI. Pooled results showed that patients with PSCI had significantly higher level of serum UA as compared to those without PSCI (mean difference: 35.70 μmol/l, 95% confidence interval (CI): 8.36 to 63.01, p=0.01; I2=95%). Subgroup analysis showed significant higher level of serum UA in patients with PSCI evaluated during follow-up of 3 months to 3 years, but not for those evaluated during hospitalization (p for subgroup difference=0.01). In addition, results of meta-analysis also showed that compared to patients with lower serum UA, AIS patients with higher serum UA had increased risk of PSCI (odds ratio: 1.33, 95% CI: 1.02 to 1.73, p=0.04; I2=72%). Higher level of serum UA after disease onset may be a marker of increased risk of PSCI in patients with AIS. Although these findings need to be validated in large-scale prospective studies, the possible mechanisms underlying the association between UA and PSCI should be also investigated.