Serum Bilirubin Level Is Increased in Metabolically Healthy Obesity

Abstract

ObjectivesBilirubin is a biochemical substance with metabolic benefits. The objective of this research was to elucidate the association between serum bilirubin levels and metabolic alterations in different obesity phenotypes.MethodsIn total, 1,042 drug-naive participants were included in the study. Of them, 541 were obese patients and 501 were age-matched and sex-matched healthy control subjects. The obese patients were divided into metabolically healthy obesity (MHO) group and metabolically unhealthy obesity (MUHO) group according to the levels of fasting plasma glucose (FBG), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and blood pressure (BP). Clinical and biochemical parameters including total bilirubin (TBil), indirect bilirubin (IBil) and direct bilirubin (DBil) were measured. ANOVA or Kruskal-Wallis H test was used to test differences among the three groups. Pearson and Spearman correlations were used to analyze the relationships between two parameters. The relationships between bilirubin and other variables were analyzed using Multivariate regression analysis.ResultsMHO group had favorable blood pressure, glucose and lipids profiles, along with increased TBil and DBil, and decreased high-sensitivity C-reactive protein (hsCRP) and homeostasis model assessment of insulin resistance (HOMA-IR) levels when compared to MUHO group (P < 0.05 for all). TBil and DBil were negatively correlated with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), fasting insulin (FINS), hsCRP and HOMA-IR, even after adjusted for age, gender and BMI (all P <0.01). Multivariate regression analysis demonstrated that HOMA-IR was independently correlated with TBil and DBIi levels (β = -0.400, P < 0.01).ConclusionMHO group harbors increased bilirubin level compared with MUHO group. HOMA-IR was independently correlated with TBil and DBIi levels.

The associations of psychopathology and metabolic parameters with serum bilirubin levels in patients with acute-episode and drug-free schizophrenia: a 5-year retrospective study using an electronic medical record system

“…Specifically, in the logistic regression analysis model, patients with a higher TB level had a lower TG level, those with a higher CB level had a lower TC level, and those with a higher UCB level had a higher HDL-C level; In the linear regression model, CB, but not UCB levels, were negatively correlated with the FBG level. The differences were also observed in the general population and schizophrenia patients in previous cross-sectional and prospective studies [ 58 , 59 ]. Bilirubin is a lipid-soluble substance, and different types of bilirubin bind differently to albumin.…”

Mildly elevated serum bilirubin and its correlations with lipid levels among male patients undergoing health checkups

“…Currently, the results of research on the association between bilirubin and lipid levels are still inconsistent. Fu et al [ 22 ] reported that TBil and DBil levels were inversely related to TC and TG levels, while no significant correlation between IBil and the two lipid levels was observed. In the study by Seyed et al [ 23 ], compared to men with low levels of bilirubin, those with mildly elevated bilirubin levels showed TG levels that were approximately 0.55 mmol/L lower.…”

Association of Low Serum Bilirubin Concentrations and Promoter Variations in the UGT1A1 and HMOX1 Genes with Type 2 Diabetes Mellitus in the Czech Population

“…In fact, bilirubin behaves as a signaling molecule acting on various nuclear and cytoplasmic receptors [ 3 , 4 ]. Apart from beneficial effects on atherosclerotic diseases [ 29 ], mildly elevated serum bilirubin concentrations seem to protect against the development of obesity, metabolic syndrome [ 7 , 8 , 9 ] as well as diabetes [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ].…”

“…In fact, this association with abnormal glucose tolerance tests was reported as early as 1996 [ 10 ]. Numerous clinical studies reporting lower serum/plasma bilirubin concentrations with the risk of diabetes (and its complications) were published in the following decade, as summarized in 2012 [ 11 ], as well as being confirmed in more recent studies [ 12 , 13 , 14 , 15 , 16 , 17 ].…”