Serum Uric Acid and Outcome after Acute Ischemic Stroke: PREMIER Study

Abstract

Background: Current evidence shows that uric acid is a potent antioxidant whose serum concentration increases rapidly after acute ischemic stroke (AIS). Nevertheless, the re-lationship between serum uric acid (SUA) levels and AIS outcome remains debatable. We aimed to describe the prognostic significance of SUA in AIS. Methods: We studied 463 patients (52% men, mean age 68 years, 13% with glomerular filtration rate <60 ml/min at hospital arrival) with AIS pertaining to the multicenter registry PREMIER, who had SUA measurements at hospital presentation. Multivariate models were constructed to analyze the association of SUA with functional outcome as assessed by the modified Rankin scale (mRS) at 30-day, 3-, 6- and 12-month follow-up. A mRS 0-1 was regarded as a very good outcome. Results: Mean SUA concentration at hospital arrival was 6.1 ± 3.7 mg/dl (362.8 ± 220.0 μmol/l). Compared with cases with higher SUA levels at hospital admission, patients with ≤4.5 mg/dl (≤267.7 μmol/l; the lowest tertile of the sample) had more cases of a very good 30-day outcome (30.5 vs. 18.9%, respectively; p = 0.004). SUA was not associated with mortality or functional dependence (mRS >2) at 30 days, or with any outcome measure at 3, 6 or 12 months poststroke. After adjustment for age, gender, stroke type and severity (NIHSS <9), time since event onset, serum creatinine, hypertension, diabetes and smoking, a SUA ≤4.5 mg/dl (≤267.7 μmol/l) was positively associated with a very good short-term outcome (odds ratio: 1.76, 95% confidence interval: 1.05-2.95; negative predictive value: 81.1%), but not at 3, 6 or 12 months of follow-up. When NIHSS was entered in the multivariate model as a continuous variable, the independent association of SUA with outcome was lost. Compared with cases with higher levels, patients with SUA ≤4.5 mg/dl (≤267.7 μmol/l) were more frequently younger than 55 years, women, with mild strokes, with normal serum creatinine and fewer had hypertension. The time since event onset to hospital arrival was not significantly associated with AIS severity or SUA levels; nevertheless, a nonsignificant tendency was observed for patients with severe strokes and high SUA levels arriving in <24 h. Conclusions: A low SUA concentration is modestly associated with a very good short-term outcome. Our findings support the hypothesis that SUA is more a marker of the magnitude of the cerebral infarction than an independent predictor of stroke outcome.

Pattern of change of serum uric acid level during acute ischemic stroke and their prognostic significance

“…However, some studies reported that the decreases in serum UA during the first week after onset of stroke correlates with more severe stroke, unfavourable stroke evolution, and poor long-term stroke outcome [9,10] . The findings of Premier study also suggests that a low SUA concentration is modestly associated with a very good short-term outcome and is more a marker of magnitude of cerebral infarction [11] . Serum uric acid is one of the major aqueous antioxidant in human beings.…”

To Study Serum Uric Acid as a Risk Factor in Acute Ischaemic Stroke

“…Study done by Chiquete et al 25 showed improved 30-day clinical outcome in patients with serum uric acid < 4.5 mg/dL (outcome assessed by Modified Rankin Scale). A cohort study by Newman et al 26 in 2006 on 140 patients also concluded that elevated serum uric acid is significantly and independently associated with increased risk of future vascular events in diabetic stroke population.…”

The effect of erythropoietin on serum uric acid levels during renal ischemia reperfusion injury in rats

“…Many clinical situations can be used to prove how SUA influences and is influenced by ischemic cases. SUA is a potent [3] antioxidant, the levels of which are rapidly increased after acute ischemic stroke (AIS). The mean SUA concentration in patients with AIS upon hospital arrival was 6.1±3.7 mg/dL.…”