Serum uric acid concentrations and risk of intracerebral hemorrhage: A systematic review and meta-analysis

Abstract

Background and aimsThe relationship between serum uric acid (UA) and the risk of intracerebral hemorrhage (ICH) remains controversial. The aim of our systematic review and meta-analysis was to ascertain the association between serum UA concentrations and the risk of ICH. MethodsWe systematically searched databases of Embase, Pubmed, Web of Science and Cochrane Library up to December 30, 2017, and additional papers were identified through a manual search. Mean difference (MD) for serum UA levels with 95% confidence intervals (CI) was calculated. Six studies, including 345 ICH patients, 574 ischemic stroke patients and 535 healthy controls, were identified for meta-analysis. ResultsOur results revealed no statistically significant differences in the comparison of UA between ICH and healthy controls (95% CI = −9.04-15.61); UA levels in patients with ischemic stroke were significantly higher than those in healthy controls (95% CI = 3.91–56.32); further subgroup analysis of age showed higher UA levels in ICH patients over 65 years than healthy controls (age≥65: 95% CI = 1.44–35.96). Subgroup of ethnicity (Asians: CI = −9.06-21.00; Caucasians: 95% CI = −68.43-8.43), gender (Men: 95% CI = −56.08-4.73; Women: 95% CI = −27.19-35.91) and sample size (large samples: 95% CI = −20.54-41.05; small samples: 95% CI = −25.41-13.78) with respect to UA levels between ICH and healthy controls did not change these results. ConclusionsThis meta-analysis showed that serum UA levels did not increase the risk of ICH probably because of the dual roles of UA, i.e. pro-oxidant and antioxidant, in the progression of atherosclerosis. However, serum UA may be a potential risk factor for ICH in the elderly. There were no race-specific differences in UA levels between Asians and Caucasians as well as gender-related differences between men and women in the risk of ICH.