U-Shaped Relationship Between Functional Outcome and Serum Uric Acid in Ischemic Stroke

Abstract

Background/Aims: We sought to assess a consecutive number of patients with first-ever acute ischemic stroke (AIS), the clinical relevance in regard to functional outcome of the serum uric acid (SUA) measured at admission. Methods: In 2 prospective centers for observational study, serum concentrations of SUA were measured on admission in the serum of 710 consecutive patients with AIS. SUA concentrations were determined by high-performance liquid chromatography. SUA, NIH stroke scale (NIHSS), and conventional risk factors were evaluated to determine their value to predict functional outcome within 3 months. Results: During the follow-up, an unfavorable functional outcome (defined as a mRS score > 2) was found in 219 (30.8%) patients. The unfavorable functional outcome distribution across the SUA quartiles ranged between 12.4% (third quartile) and 50.6% (first quartile). After adjusting for all other significant outcome predictors, SUA concentration remained an independent unfavorable outcome predictor with an adjusted OR of 0.996 (95% CI, 0.993-0.998; P< 0.001). Conclusions: The data show that the U-shaped nature of the exposure-risk relationship was more prominent when the data were assessed in deciles (based on the SUA values). This model predicted the lowest relative risk of unfavorable outcome in the 67th percentile (corresponding to 309 µmol/L). SUA was significantly associated with the risk of poor functional outcomes in Chinese patients with stroke.