Lower serum uric acid level strongly predict short-term poor functional outcome in acute stroke with normoglycaemia: a cohort study in China.

BACKGROUND: Conflicting results on the correlation between hyperuricemia and the prognosis of stroke had been reported and the close association between serum uric acid (SUA) and abnormal glycomatabolism might further complicate the assessment of the correlation. We aimed to investigate SUA in predicting the prognosis of acute stroke in different glycometabolism status.

METHODS: A total of 2907 patients aged from 18 to 85 (1220 diabetes mellitus (DM), 777 prediabetes and 910 normoglycemia) were selected from the Abnormal Glucose Regulation in Patients with Acute Stroke across China (ACROSS-China) study. The patients were divided into groups according to the SUA quartile as well as decile. The correlations between SUA and the poor outcome (mRS > 2) at discharge were assessed stratified by glucose metabolism status. Multivariate logistic regression was used to analyze the potential risk factors of poor in-hospital outcome of stroke and the risk-adjustment of the correlation between SUA and the prognosis of stroke. P < 0.05 was considered statistically significant.

RESULTS: SUA were divided first as Quartile1 to 4 (Quartile1 < 221 μmol L-1 ; Quartile2 (221-286) μmol L-1 ; Quartile3 (286-352) μmol L-1 and Quartile4 > 352 μmol L-1 ), then as decile1 to 10. In normoglycaemia, SUA quartiles, deciles and continuous SUA concentration were independently significantly associated with poor outcome. Q1 was independently associated with the higher possibility of poor functional outcome (compared to Q4, odds ratios (ORs) with 95% confidential interval (CI) was 3.79 (1.23-8.67) in Q1); Lower level of SUA in DM was also associated with poor functional outcome at discharge compared to the highest level of SUA(Q4)(OR with 95% CI, 2.07 (1.05-4.08)), however, lower SUA level was also related to severer stroke at admission in DM as well as in prediabetes (P < 0.001 in DM and 0.023 in prediabetes) and severer stroke resulted in worse functional outcome at discharge (OR with 95% CI, 12.15 (8.08-18.21) in DM and 11.58 (7.50-23.25) in prediabetes). But in normoglycamic stroke, SUA levels did not differ in stroke severity at admission (P = 0.066).

CONCLUSIONS: Low SUA level (<221 μmol L-1 ) independently and strongly predicts the short-term poor functional outcome in acute stroke with normoglycaemia other than diabetes or prediabetes.