Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
Cerebrovasc Dis. 2013;35(2):168-74. doi: 10.1159/000346603. Epub 2013 Feb 22.
Current evidence shows that uric acid is a potent antioxidant whose serum concentration increases rapidly after acute ischemic stroke (AIS). Nevertheless, the relationship between serum uric acid (SUA) levels and AIS outcome remains debatable. We aimed to describe the prognostic significance of SUA in AIS.
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.
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.
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.
目前的证据表明，尿酸是一种有效的抗氧化剂，急性缺血性脑卒中（AIS）后其血清浓度迅速升高。然而，血清尿酸（SUA）水平与 AIS 预后之间的关系仍存在争议。我们旨在描述 SUA 在 AIS 中的预后意义。
我们研究了来自多中心 PREMIER 登记处的 463 名 AIS 患者（52%为男性，平均年龄 68 岁，入院时 13%的肾小球滤过率<60ml/min），这些患者在入院时进行了 SUA 测量。构建多变量模型以分析 SUA 与功能结局的关联，功能结局通过改良 Rankin 量表（mRS）在 30 天、3 个月、6 个月和 12 个月的随访中进行评估。mRS 0-1 被认为是非常好的结局。
入院时的平均 SUA 浓度为 6.1±3.7mg/dl（362.8±220.0μmol/l）。与入院时 SUA 水平较高的病例相比，SUA 水平≤4.5mg/dl（≤267.7μmol/l；样本中最低三分位数）的病例在 30 天时具有更好的非常好结局的比例更高（分别为 30.5%和 18.9%；p=0.004）。SUA 与 30 天的死亡率或功能依赖（mRS>2），或与任何 3、6 或 12 个月的预后测量无关。在校正年龄、性别、卒中类型和严重程度（NIHSS<9）、发病时间、血清肌酐、高血压、糖尿病和吸烟后，SUA≤4.5mg/dl（≤267.7μmol/l）与短期非常好的结局呈正相关（优势比：1.76，95%置信区间：1.05-2.95；阴性预测值：81.1%），但在 3、6 或 12 个月的随访中没有相关性。当 NIHSS 作为连续变量纳入多变量模型时，SUA 与结局的独立相关性丢失。与高水平的病例相比，SUA 水平≤4.5mg/dl（≤267.7μmol/l）的患者更年轻，女性更多，卒中更轻，血清肌酐正常，高血压患者更少。发病至入院的时间与 AIS 严重程度或 SUA 水平无显著相关性；然而，发病至入院时间短于 24 小时的严重卒中患者和高 SUA 水平患者存在非显著趋势。
低 SUA 浓度与短期非常好的结局适度相关。我们的研究结果支持 SUA 更像是脑梗死严重程度的标志物，而不是卒中预后的独立预测因子的假说。
