Abstract
BACKGROUND: Unconjugated bilirubin (UCB) plays a protective role in coronary artery disease. Red cell distribution width (RDW), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) are inflammatory biomarkers and higher levels are related to atherosclerosis and adverse cardiovascular events. AIM: We aimed to investigate the relation between UCB levels and RDW, NLR, PLR in people with Gilbert's syndrome (GS). MATERIALS AND METHODS: We selected 2166 subjects (1082 with GS and 1084 healthy controls) from a database having 33,695 people. RDW, NLR and PLR were investigated in the subjects with GS and compared with the healthy controls. Linear regression analysis was used to evaluate the relation between variables. RESULTS: NLR and PLR were higher in the subjects with GS compared to the controls (p < 0.001). RDW was similar in both groups (p = 0.318). UCB was negatively correlated with lymphocyte counts (p = 0.040), and positively correlated with RDW (p < 0.001) and PLR (p = 0.037) in the subjects with GS. There was no significant correlation between UCB and NLR (p = 0.078). RDW (p < 0.001) and lymphocyte counts (p = 0.030) were significantly associated with UCB levels in the regression analysis conducted in the subjects with GS. CONCLUSION: There is a negative association between UCB and NLR, PLR due to low amounts of lymphocyte counts, which causes increased risk of CVD. These results suggest that the cardio-protective effect of UCB is due to both anti-oxidative and anti-inflammatory ways indirectly.