We aimed to examine changes in serum bilirubin and uric acid (UA) levels in subcortical ischemic vascular disease (SIVD). In addition, we investigated if altered serum bilirubin and UA levels correlate with the subtypes of SIVD as well as the severity of leukoaraiosis (LA).

This cross-sectional study included 1098 consecutive patients with slight symptoms, such as dizziness, vertigo etc. According to magnetic resonance imaging (MRI) appearances, they were divided into either SIVD group or controls (CN), and the SIVD group was further grouped in lacunar infarction (LI) and LA subtypes, as well as different grades. Serum bilirubin and UA levels were determined by the vanadate oxidase method and enzymatic method respectively, after at least an eight hour overnight fasting, in all subjects.

The bilirubin level was obviously lower while the UA level was significantly higher in the SIVD group when compared with the controls. Moreover, the LA subgroup presented more significant changes in bilirubin and UA when compared to the LI subgroup in both males and females. The correlation was positive between the UA levels and the LA severity (r=0.134, p=0.006). Multivariate regression analysis revealed that the odds ratio (95% CI) for SIVD in the lowest tertile of total bilirubin (Tbil<9.58μmol/L) and highest tertile of UA (UA>339μmol/L) were 2.702(1.936–3.770) and 2.135(1.521–2.996) respectively after adjusting for confounding variables.

Serum bilirubin levels were lower, whereas UA levels were higher in SIVD patients when compared with controls in both males and females, especially in LA patients. Moreover, serum UA levels positively correlated to LA severity.