Prognostic significance of uric acid change in acute ischemic stroke patients with reperfusion therapy

Background Uric acid (UA) is an important endogenous free radical scavenger that has been found to have a neuroprotective effect. However, there is uncertainty about the relationship between UA change and outcome in acute ischemic stroke (AIS) patients with reperfusion therapy. Methods We consecutively enrolled AIS patients with reperfusion therapy. UA was measured upon admission and during hospitalization. The change in UA levels (Delta UA) was determined by calculating the difference between admission UA and the lowest UA among all follow-up measurements, with a positive Delta UA suggesting a decrease in UA levels. Functional outcome was assessed by modified Rankin Scale (mRS) at 3 months. Poor outcome was defined as mRS >2. Results A total of 361 patients were included (mean age 68.7 +/- 13.9 years, 54.3% males). The mean UA on admission was 355 +/- 96.1 mu mol/L. The median Delta UA was 121 mu mol/L (IQR 50-192 mu mol/L) and 18 (5%) patients had increased UA levels. UA on admission was positively associated with good outcome (p for trend = 0.017). When patients were classified into quartiles by Delta UA, patients with the largest decrease in UA (Q4: 199-434 mu mol/L) had a higher risk of poor outcome at 3 months compared to patients with the least decrease in UA (Q1: 0-57 mu mol/L) (OR 2.55, 95% CI 1.09-5.98, p = 0.031). The risk of poor outcome increased with Delta UA (p for trend = 0.048). Conclusions In patients with reperfusion therapy, high UA on admission was associated with a good 3-month outcome, while a greater decrease in UA was associated with poor outcome.