Title:Serum Bilirubin after Acute Ischemic Stroke is Associated with Stroke Severity
VOLUME: 9 ISSUE: 2
Author(s):Yun Luo, Jing-Wei Li, Zheng-Juan Lu, Chong Wang, De-Ning Guan and Yun Xu
Affiliation:Department of Neurology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China.
Keywords:Bilirubin, acute ischemic stroke, severity, Elevated serum , Bilirubin , Multinomial logistic , regression analysis, Spearman , antiinflammatory, neuroprotectant properties, cerebrovacular diseases, haemorrhage, diabetes mellitus
Abstract:Elevated serum bilirubin was prevalent in the acute ischemic stroke (AIS), which was induced in response to
oxidative stress and could display the intensity of oxidative stress. As more severe stroke is linked with higher level of
oxidative stress, we hypothesized that bilirubin may be associated with the severity of stroke. In this study, bilirubin and
other biochemical indexes were measured in 531 enrolled patients with AIS, and NIH Stroke Scale (NIHSS) scores were
assessed simultaneous with blood collection. The association between bilirubin and the severity of stroke was performed
by Spearman correlation analyze, and the level-risk relationship of bilirubin in different level of NIHSS score was
performed through Multinomial logistic regression analysis. We performed multivariable logistic regression to estimate
odds ratios (OR) and 95% confidence intervals (CI) of severe stroke dichotomized as NIHSS≥8 with adjustment for other
stroke risk factors, the level-risk relationship of severe stroke in different level of bilirubin was also performed through
Multinomial logistic regression analysis. We found that NIHSS score was significantly positively correlated with both
serum direct bilirubin (Dbil, R=0.229 and P=0.000) and total bilirubin (Tbil, R=0.224 and P=0.000), higher level of serum
bilirubin linked to the higher NIHSS score with OR(95% CI) in upper level of NIHSS score group was 1.12(1.01-1.24),
1.23(1.11-1.36), 1.31(1.15-1.51) in Dbil and 1.01(0.99-1.31), 1.05(1.03-1.08), 1.07(1.03-1.11) in Tbil compared to the
lowest level group. In unadjusted or adjusted logistic regression analyses, serum Dbil and Tbil still have a significant
association with the severe stroke. When both the Dbil and Tbil concentrations were grouped into 4 levels, participants
with higher levels of bilirubin showed higher risk with severe stroke compared with the lowest level of bilirubin, with
OR(95% CI) 1.881(1.04-3.404) of Dbil in level 3 and 3.702(1.979-6.927) of Tbil, 3.352(1.572-7.147) of total bilirubin in
level 4. As a conclusion, serum bilirubins were in significant correlation with severity of AIS, which may be served as
useful markers to reflect the degree of illness.