Influence of recanalization on uric acid patterns in acute ischemic stroke.

Background: Most epidemiological studies have reported a significant association between elevated serum levels of uric acid (UA) and increased cardiovascular disease. On the other hand, UA is the most abundant antioxidant in the human body. We hypothesized that UA levels would change noticeably in association with the degree of oxidative stress in acute ischemic stroke.

Methods: We analyzed consecutive patients with acute ischemic stroke in the anterior circulation system within 24 h of symptom onset, confirmed by diffusion-weighted imaging (DWI), and with a modified NIH Stroke Scale (mNIHSS) score of 5 or greater. Baseline demographics, serial clinical scores, serial UA and allantoin (a nonenzymatic metabolite of UA) levels, UA change (baseline UA - UA at 48 h), and DWI lesion volumes were compared between 45 patients with recanalized vessels (RV) and 43 patients with nonrecanalized vessels (NV) in follow-up imaging.

Results: The RV (vs. NV) patients were more likely to receive thrombolytic treatment (p = 0.005), achieve a reduction in day-14-mNIHSS scores (p = 0.001), and greater changes in UA (p = 0.024) and allantoin levels (p = 0.003). The UA levels dropped at 48 h and gradually increased in a U-shaped pattern. UA change (r = 0.360; p = 0.001) rather than baseline UA (r = 0.044; p = 0.681) was significantly correlated with infarct volume. In the RV (vs. NV) patients, there was a stronger association between infarct volume and UA change (r = 0.483; p = 0.001) or allantoin levels (r = 0.466; p = 0.017).

Conclusion: Our results suggest that UA might be a consumptive and reproducible antioxidant in acute ischemic stroke, and this pattern appears to be influenced by recanalization success and infarct volume size.