Adiposity mediates the association between bilirubin, glucose/insulin homeostasis and inflammation. (25th November 2020)

• Record Type: Journal Article
• Authors: Mazidi, M; Katsiki, N; Mikhailidis, D.P; Banach, M
• Is Part Of: European heart journal. Volume 41:(2020)Supplement 2
• Publication Date: 2020-11-25
• Subjects: Obesity; Cardiology -- Periodicals; Heart -- Diseases -- Periodicals; 616.12005
• DOI: 10.1093/ehjci/ehaa946.3039
• Languages: English
• ISSNs: 0195-668X

Abstract

Abstract: Background and purpose: The exact contribution of adiposity on the link between bilirubin and glucose/insulin homeostasis and inflammatory factors has not been defined. We aimed to quantify the role of adiposity on this association. Methods: The variables of interest were extracted from the National Health and Nutrition Examination Survey (NHANES 2005–2010). We assessed the role of body mass index (BMI) as an adiposity factor. Analysis of co-variance and causal mediation analysis were conducted based on survey design and sample weights. Results: Overall, 10, 880 men and 11, 462 women were included in the present analysis (mean age=47.2 years). Mean circulating bilirubin for the overall population, men and women was 0.74±0.02, 0.83±0.03 and 0.65±0.03 mg/dl, respectively (p<0.001, for the comparison between sexes). In an adjusted model, glucose/insulin homeostasis and inflammatory factors were more favorable for participants with a higher level of bilirubin in both sexes (p<0.001 for all). The extent of the mediation was maximal between the homeostatic model assessment of insulin resistance and bilirubin (men: 45%, women: 58%). In post-menopausal women, 47 and 13% of the changes in insulin and triglyceride-glucose index in response to bilirubin levels could be explained by alterations in BMI. In smokers, BMI could mediate 53% of the association between bilirubin and insulin (p<0.001). Similar results were obtained when participants with normal liver function were analyzed separately (see Figure). Conclusions: Using advanced statistical techniques we analyzed the complex link of bilirubin with inflammation and glucose/insulin homeostasis and identified a role for adiposity. We also suggest that bilirubin has an anti-inflammatory role. Funding Acknowledgement: Type of funding source: None