Serum total bilirubin concentration is associated with carotid atherosclerosis in patients with prehypertension

Objectives: Bilirubin has been demonstrated to be linked with anti-inflammatory and antioxidant progress. We aimed to evaluate the association between serum total bilirubin level and carotid intima-media thick-ness (cIMT) in patients with prehypertension.

We consecutively enrolled pre-hypertensive patients from a community in Guangzhou between January 2017 and January 2018. All patients underwent carotid artery ultrasonography measurement. The correlation between serum total bilirubin and cIMT was assessed by using the Pearson's correlation coefficient. Multiple logistic regression analysis was performed to assess the independent association between clinical parameters and carotid atherosclerosis.

A total of 691 subjects with prehypertension were included in this study. There were 101 patients with increased cIMT (mean age 52.69 ± 11.58 years; 50 male) and 590 subjects with normal cIMT (mean age50.28 ± 10.33 years; 332 male). We found that cIMT was significantly related with systolic blood pressure(r = 0.257, P < 0.001), C-reactive protein (r = 0.327, P < 0.001), total cholesterol (r = 0.218, P = 0.002) and total bilirubin (r =-0.489, P < 0.001). A multiple logistic regression analysis revealed that total bilirubin was an independent factor for atherosclerosis (OR = 0.476; 95%CI: 0.253, 0.764; P < 0.001).

Our results suggested that serum total bilirubin was inversely related with cIMT, and might be an early clinical marker for predicting the occurrence of subclinical carotid atherosclerosis in patients with prehypertension.