Development of a model for prediction of coronary atherosclerotic regression: evaluation of high-density lipoprotein cholesterol level and peripheral blood monocyte count

Independent and joint associations of monocyte to high-density lipoprotein-cholesterol ratio and body mass index with cardiorenal syndrome: insights from NHANES 2003-2020

BACKGROUND

With the development of pathophysiology, cardiorenal syndrome (CRS), a complex and severe disease, has received increasing attention. Monocyte to high-density lipoprotein-cholesterol ratio (MHR) and body mass index (BMI) are independent risk factors for cardiovascular diseases, but their association with CRS remains unexplored. This study aims to explore the independent and joint effects of MHR and BMI on CRS.

METHODS

We included 42,178 NHANES participants. The determination of CRS referred to the simultaneous presence of cardiovascular disease (identified through self-report) and chronic kidney disease (eGFR < 60 mL/min per 1.73 m²). We employed multivariate weighted logistic regression to evaluate the odds ratio (OR) and 95% confidence interval (CI) for the independent and joint associations of MHR and BMI with CRS. We also conducted restricted cubic spines to explore nonlinear associations.

RESULTS

The prevalence of CRS was 3.45% among all participants. An increase in both MHR and BMI is associated with a higher risk of CRS (MHR: OR = 1.799, 95% CI = 1.520-2.129, P < 0.001, P-trend < 0.001; BMI: OR = 1.037, 95% CI = 1.023-1.051, P < 0.001). Individuals who simultaneously fall into the highest quartile of MHR and have a BMI of 30 or more face the highest risk of CRS compared to those in the lowest MHR quartile with a BMI of less than 25 (OR = 3.45, 95% CI = 2.40-4.98, P < 0.001). However, there is no interactive association between MHR and BMI with CRS.

CONCLUSIONS

Higher MHR and BMI are associated with higher odds of CRS. MHR and BMI can serve as tools for early prevention and intervention of CRS, respectively.

Which Biomarker(s) Augment the Diagnostic Value of the Positive Exercise Electrocardiography Test: Systemic Inflammatory Index, Plasma Atherogenic Index, or Monocyte/HDL-C Ratio?

The exercise electrocardiography test (EET) is still used before coronary angiography in the diagnosis of chronic coronary syndromes. This study aimed to demonstrate the value of the combination of a positive EET with the systemic inflammatory index (SII), the plasma atherogenic index (PAI), and the monocyte/HDL-C ratio (MHR) in the determination of obstructive coronary artery disease (CAD). This single-center, retrospective study included 540 patients who underwent coronary angiography after ETT. The patients were separated into Group 1, comprising 434 patients with normal coronary arteries and non-obstructive CAD, and Group 2, including 106 with obstructive CAD. In Group 2, the patients were separated into SYNTAX ≤ 22 or ≥23. Glucose, low-density lipoprotein, white blood cells, and MHR were determined to be significantly higher in Group 2 (p < 0.05). According to the multivariate logistic regression analysis, age, gender, diabetes mellitus, and low-density lipoprotein were determined to be independent predictors of CAD. In the ROC curve analysis, a cut-off value of 12 for the MHR in the determination of obstructive CAD had a sensitivity of 60.4% and a specificity of 53.0%. The main result of this study was that a high MHR is an indicator of obstructive CAD in patients with positive EET and suspected CAD.

The association between monocyte to high-density lipoprotein cholesterol ratio and clinical prognosis of acute ischemic stroke after intravenous thrombolysis therapy

The monocyte-to-high-density lipoprotein cholesterol (HDL) ratio (MHR) is accepted as a novel marker for demonstrating inflammation. We investigated whether the monocyte-to-HDL ratio is related to the 90-day clinical prognosis of acute ischemic stroke (AIS) after intravenous thrombolysis (IVT). Patients with AIS treated with alteplase IVT were included consecutively, and clinical information and laboratory data were collected. The 90-day prognosis of all patients was determined with a clinical assessment using the modified Rankin Scale (mRS). The optimal cutoff values for patients were evaluated by the receiver operating characteristic (ROC) curve method. Then, a multivariate logistic regression model was used to evaluate the risk factors for poor prognosis of IVT in AIS. We retrospectively enrolled 192 patients who were diagnosed with AIS and received IVT between February 2020 and July 2022, with final follow-up on September 30, 2022. The patients in the poor prognosis group had significantly higher monocyte counts, lower HDL levels, and higher MHR values than the good prognosis group. The optimal cutoff value of the MHR for predicting the 3-month outcome of acute pontine infarction was 0.621. Multivariate logistic regression revealed that the MHR (OR = 4.626, 95% CI: 1.156-18.512, P = .030) was strongly associated with poor prognosis in AIS. The MHR is an independent risk factor for the clinical prognosis of AIS patients receiving IVT therapy and shows a certain predictive value.

Monocyte to high-density lipoprotein ratio is associated with mortality in patients with coronary artery diseases

BACKGROUND

Whether the monocyte to high-density lipoprotein ratio (MHR) is associated with the prognosis of coronary artery disease (CAD) is inconclusive.

METHODS

Patients with CAD were enrolled and their data were collected. Blood was sampled within 24 h after admission. Multivariate Cox regression analysis was performed to determine the relationship between the MHR and all-cause mortality as well as complications during hospitalization.

RESULTS

We included 5371 patients in our cohort study. Among them, 114 (2.12%) patients died in hospital. MHR was independently associated with all-cause mortality (hazard ratio [HR], 1.81; 95% confidence interval [CI] 1.35, 2.42), cardiovascular mortality (1.69; 1.17, 2.45) and non-cardiovascular mortality (2.04; 1.27, 3.28). This association was only observed in patients with hypertension (P for interaction = 0.003). Patients with higher MHR levels also have a higher risk of complications, including infection, pneumonia, electrolyte disturbance, gastrointestinal bleeding, multiple organ dysfunction syndrome, and disturbance of consciousness. The receiver operating characteristic (ROC) analysis showed that the MHR had higher prognostic values than monocytes and high-density lipoprotein.

CONCLUSION

MHR was an independent predictor of all-cause mortality and in-hospital complications in patients with CAD, especially in patients with hypertension.

Association between monocyte to high-density lipoprotein cholesterol ratio and multi-vessel coronary artery disease: a cross-sectional study

BACKGROUND

Patients with multi-vessel coronary artery disease (MV-CAD) have poorer clinical outcomes than those with single-vessel coronary artery disease (SV-CAD). Solid evidence underlines that high-density lipoprotein cholesterol (HDL-C) plays a protective role and monocyte plays a negative role in coronary artery disease (CAD). However, the monocyte to high-density lipoprotein ratio (MHR) has not been studied in relation to MV-CAD.

METHODS

In this study, 640 patients underwent coronary angiography, of whom 225 had severe coronary artery disease. Then divide the above two groups of patients into three groups based on the MHR tertiles, respectively. Logistic regression and subgroup analysis were carried out to estimate the association between MHR and MV-CAD. The receiver operating characteristic (ROC) curve analysis was constructed by combining classic CAD risk factors with MHR in response to MV-CAD. In addition, the mediating effect of MHR between smoking and MV-CAD in suspected CAD Patients was analyzed.

RESULTS

Among the three MHR groups, a statistically discrepant was observed in the number of patients with CAD, Severe-CAD and MV-CAD (PCAD < 0.001; PSevere-CAD < 0.001; PMV-CAD = 0.001) in suspected CAD patients. Furthermore, the number of patients with MV-CAD (P < 0.001) was different in Severe-CAD patients among three MHR groups. Non-CAD and CAD patients showed statistically discrepant in MHR levels (P < 0.001), and this difference also was observed between SV-CAD and MV-CAD patients (P < 0.001). In the analysis of suspected CAD patients, a significantly positive relationship was found between MHR and CAD, Severe-CAD, and MV-CAD (P for trend < 0.001). The effect of MHR on MV-CAD was consistent across all subgroups, with no significant randomized factor-by-subgroup interaction (P-interaction = 0.17-0.89). ROC analysis showed that the model constructed with MHR and classic influencing factors of CAD was superior to the model constructed solely based on classic influencing factors of CAD (0.742 vs.0.682, P = 0.002). In the analysis of Severe-CAD patients, patients with higher MHR levels had a higher risk of MV-CAD [OR (95%CI): 2.90 (1.49, 5.62), P for trend = 0.002] compared to patients with lower MHR. The trends persisted after adjusting for demographic (P for trend = 0.004) and classic influencing factors of CAD (P for trend = 0.009). All subgroup factors for patients with MV-CAD had no interaction with MHR (P-interaction = 0.15-0.86). ROC analysis showed that the model combining MHR and classic influencing factors of CAD was superior to the one including only the classic influencing factors of CAD (0.716 vs.0.650, P = 0.046). Assuming that MHR played a mediating effect between smoking and MV-CAD in suspected CAD patients. The results indicated that MHR played a partial mediating effect of 0.48 (P < 0.001).

CONCLUSION

A higher MHR was mainly associated with multi-vessel coronary artery disease and MHR partially mediated the association between smoking and MV-CAD.

Monocyte to high-density lipoprotein ratio predict long-term clinical outcomes in patients with coronary heart disease: A meta-analysis of 9 studies

BACKGROUND

A novel inflammation-related biomarker, the monocyte to high-density lipoprotein cholesterol ratio (MHR), had a great relation to the development and prognosis of coronary atherosclerotic heart disease. Current study was to investigate whether the MHR was a potential tool in predicting the mortality and major adverse cardiac events (MACEs) in patients suffering coronary heart disease (CHD) by meta-analysis.

METHODS

The Cochrane Library, PubMed, MEDLINE, Scopus, EMBASE, and Web of science were searched for relevant cohort studies published prior to February 10, 2022. The association between MHR and mortality/MACEs was analyzed in patients with CHD. Hazard ratios (HR) with 95% confidence interval (CI) were calculated to estimate the strength of association.

RESULTS

In the meta-analysis, a total of 9 studies of 11,345 patients with CHD were included. Compared with the low level of MHR group, the high MHR value was associated with higher long-term MACEs (HR = 1.72 95% CI 1.36-2.18, P < .001), long-term mortality (HR = 1.71, 95% CI 1.10-2.66, P = .017), and in-hospital mortality/MACEs (HR = 2.82, 95% CI = 1.07-7.41, P = .036).

CONCLUSIONS

This study suggested that increased MHR value might be associated with higher long-term mortality and long-term MACEs in CHD patients. MHR might serve as a potential prognostic indicator for risk stratification in patients with CHD.

High ratio of monocytes to high-density lipoprotein is associated with hemorrhagic transformation in acute ischemic stroke patients on intravenous thrombolysis

Background

Hemorrhagic transformation (HT) is a frequent, serious complication in acute ischemic stroke patients on intravenous thrombolysis. Here we investigated whether risk of HT is associated with the ratio of monocyte count to high-density lipoprotein level (MHR).

Materials and methods

Medical records were retrospectively examined for consecutive patients with acute ischemic stroke who received thrombolytic therapy. HT was diagnosed by computed tomography at 24–36 h after therapy. Potential association between MHR and HT was examined using logistic regression.

Results

A total of 340 patients were analyzed, and their median MHR was 0.44 (0.31–0.59). MHR was higher in the 51 patients (15.0%) with HT than in those who did not suffer HT (0.53 vs. 0.42, P = 0.001). Multivariate logistic regression showed that, after adjusting for potential confounders, MHR was an independent risk factor for HT (OR 7.50, 95% CI 1.64 to 34.35, P = 0.009). Risk of HT was significantly higher among patients whose MHR fell in the third quartile (0.42–0.53) and the fourth quartile (&gt; 0.53) than among those with MHR in the first quartile (&lt; 0.31; OR 3.53, 95% CI 1.11 to 11.20, P = 0.032; OR 4.79, 95% CI 1.49 to 15.42, P = 0.009).

Conclusion

High MHR may be independently associated with higher risk of HT in patients with acute ischemic stroke on intravenous thrombolysis.

Role of monocyte to high-density lipoprotein cholesterol ratio in predicting left atrial enlargement in hypertensive patients

OBJECTIVE

Left atrium enlargement is common in hypertension due to left atrium inflammation. Monocyte to high-density lipoprotein cholesterol ratio, an inflammation marker that has become very popular in recent years, is associated with many cardiovascular diseases. The aim of this study is to investigate the monocyte to high-density lipoprotein cholesterol ratio level to predict the Left atrium enlargement in hypertensive patients.

METHODS

A total of 216 participants (i.e., 115 hypertensive and 101 control group) were enrolled. Left atrial volumes and left atrial volume indexes were calculated using transthoracic echocardiography. The monocyte to high-density lipoprotein cholesterol ratio was calculated as the ratio of monocyte to high-density lipoprotein cholesterol levels.

RESULTS

The left atrial volumes, left atrial volume indexes, and monocyte to high-density lipoprotein cholesterol levels were significantly higher in the hypertensive group than in the control group (43.3±12.4 versus 31.4±7.9, p<0.001; 22.9±5.8 versus 17.1±3.7, p<0.001; 11.4 [4.2-25.0] versus 8.4 [3.5-18.0], p<0.001, respectively). On the multivariate logistic regression analysis, monocyte to high-density lipoprotein cholesterol ratio (OR 1.38; 95%CI 1.20-1.57; p<0.001), (OR 1.28; 95%CI 1.16-1.42; p<0.001), age, and sex (female) were the independent predictors for hypertension.

CONCLUSIONS

The increased monocyte to high-density lipoprotein cholesterol ratio level was associated with hypertension and increased left atrial volume indexes. The results of this study supported the presence of inflammation, measured with a readily available and inexpensive marker, in hypertensive patients and revealed the association with left atrial enlargement.

Serum 25-Hydroxyvitamin D Is Inversely Associated with Monocyte Percentage to HDL Cholesterol Ratio among Young Healthy Adults in Qatar

Low serum 25-hydroxyvitamin D [25(OH)D] is linked to an altered lipid profile. Monocytes play an important role in inflammation and lipid metabolism. Recently, monocyte percentage to HDL-cholesterol ratio (MHR) has emerged as a novel marker of inflammation. We investigated the association between serum 25(OH)D concentrations and MHR and serum lipids in young healthy adults. Data from the Qatar Biobank were utilized to investigate the relation between serum 25(OH)D and inflammation and serum lipid concentrations in healthy Qatari adults using multivariate regression analysis. Prevalence of serum 25(OH)D concentrations <12 ng/mL (deficiency), 12-20 ng/mL (insufficiency), and ≥20 ng/mL (sufficiency) were 55.8%, 29.9%, and 14.3%, respectively. Serum 25(OH)D was significantly inversely associated with monocyte percentage, MHR, total cholesterol, LDL-cholesterol, and triacylglycerol in multivariable adjusted analysis. MHR could be a potential biomarker to predict cardiometabolic diseases among young healthy Qataris.

The new prognostic factor for pulmonary embolism: The ratio of monocyte count to HDL cholesterol

PURPOSE

Aim of this study is to investigate effectiveness of the monocyte to HDL cholesterol ratio in patients diagnosed with pulmonary embolism for predicting intra-hospital mortality.

METHOD

A total of 269 patients diagnosed with pulmonary embolism in the emergency clinic were included in the study. Study was conducted retrospectively. Pulmonary Embolism Severity Index (PESI), Monocyte count and high density lipoprotein cholesterol (HDL) values were determined. MHR values of the patients were calculated. SPSS 26 package program was used to investigate the effectiveness of MHR in predicting mortality.

FINDINGS

Mean age of the patients was 64.51 ± 12.4 years. PESI, Number of monocytes and MHR were significantly higher in the group with mortality than the group without mortality (p < .05). HDL values were significantly lower (p < .05) in mortality group. Sensitivity of MHR 19 cut off value was 89.3%, and its specificity was 82.0%.

CONCLUSION

Use of predictors for mortality estimation in patients diagnosed with acute pulmonary embolism is important for faster administration of treatment modalities. We think MHR values can be used as a strong predictor according to the hemogram parameters and biochemical results.

The Monocyte/High Density Lipoprotein Cholesterol Ratio (MHR) as an Indicator of the Need for Amputation in Patients With Peripheral Artery Disease Developing Critical Limb Ischemia

The monocyte/high density lipoprotein cholesterol ratio (MHR) reflects the proatherogenic and antiatherogenic balance, and a high ratio is associated with the severity of atherosclerosis. We measured the MHR of patients with critical limb ischemia (CLI) due to peripheral artery disease (PAD) requiring amputation. Patients diagnosed with PAD were divided into 2 groups; those who underwent an amputation due to CLI without any sign of infection and those treated with surgical or percutaneous revascularization or followed up medically. A healthy control group was also included. In patients diagnosed with PAD (n = 563), the MHR value was higher for the control group (n = 200), (12.4 ± 0.42 vs 11.5 ± 0.28, P < .001). In the amputation group, the MHR was significantly higher for the group treated by other methods (15.7 ± 1.52 vs 12.8 ± 1.45, P < .001). Possible confounding factors affecting the MHR value were determined by the univariate regression analysis, and the multiple regression analysis revealed that MHR was an independent predictor of amputation in patients with PAD (P < .001). This study suggests that the MHR may be the predictor of amputation risk in patients with PAD and CLI.

Monocyte-to-HDL-cholesterol ratio as a prognostic marker in cardiovascular diseases

Inflammation and lipid accumulation are two basic hallmarks of atherosclerosis as a chronic disease. Inflammation not only is a local response but can also be considered as a systemic process followed by an elevation of inflammatory mediators. Monocytes are a major source of proinflammatory species during atherogenesis. In atherosclerosis, modified low-density lipoproteins (LDLs) are removed by macrophages; these are recruited in the vessel wall, inducing the release of inflammatory cytokines in inflamed tissue. Hence, inflammatory cholesterol ester-loaded plaque is generated. High-density lipoprotein-cholesterol (HDL-C) exhibits antiatherosclerotic effects by neutralizing the proinflammatory and pro-oxidant effects of monocytes via inhibiting the migration of macrophages and LDL oxidation in addition to the efflux of cholesterol from these cells. Furthermore, HDL plays a role in suppressing the activation of monocytes and proliferation-differentiation of monocyte progenitor cells. Thus, accumulation of monocytes and reduction of HDL-C may participate in atherosclerosis and cardiovascular diseases (CVD). Given that the relationship between the high number of monocytes and low HDL-C levels has been reported in inflammatory disorders, this review focused on understanding whether the monocyte-to-HDL ratio could be a convenient marker to predict atherosclerosis development and progression, hallmarks of CV events, instead of the individual monocyte count or HDL-C level.

The role of monocytosis and neutrophilia in atherosclerosis

Monocytosis and neutrophilia are frequent events in atherosclerosis. These phenomena arise from the increased proliferation of hematopoietic stem and multipotential progenitor cells (HSPCs) and HSPC mobilization from the bone marrow to other immune organs and circulation. High cholesterol and inflammatory signals promote HSPC proliferation and preferential differentiation to the myeloid precursors (i.e., myelopoiesis) that than give rise to pro-inflammatory immune cells. These cells accumulate in the plaques thereby enhancing vascular inflammation and contributing to further lesion progression. Studies in animal models of atherosclerosis showed that manipulation with HSPC proliferation and differentiation through the activation of LXR-dependent mechanisms and restoration of cholesterol efflux may have a significant therapeutic potential.

Remodeling pattern is related to the degree of coronary plaque regression induced by pitavastatin: a sub-analysis of the TOGETHAR trial with intravascular ultrasound and coronary angioscopy

This study aimed to clarify the relationships between arterial remodeling patterns and plaque volume regression or stabilization. The TOGETHAR trial is a prospective open-label trial designed to assess coronary plaque regression and stabilization with multiple plaque imaging modalities following 52 weeks of pitavastatin treatment (2 mg/day). Coronary plaques were observed in 46 patients with both angioscopy and intravascular ultrasound at baseline and after 52 weeks of drug treatment. We divided these patients into three groups according to their remodeling indices (RI). Group P consisted of patients with a baseline RI >1.05, Group M of patients with a baseline RI of 0.95-1.05, and Group N of patients with a baseline RI <0.95 and then evaluated differences in coronary plaque volume changes and yellow grade among the three groups. In the positive remodeling group, whose remodeling index (RI) exceeded 1.05 at baseline, RI and percent atheroma volume (PAV) were significantly reduced (RI 1.14 ± 0.07 to 1.05 ± 0.10, p = 0.010, PAV 47.3 ± 8.3 to 45.3 ± 7.3 mm(3), p = 0.048). There was no relationship between baseline RI and the change in yellow grade of plaque. RI increased without significant change of PAV or a decrease in lumen volume in group N, with RI below 0.95 at baseline. Plaques with positive remodeling were more likely to have plaque volume regression by pitavastatin than those without in patients with coronary artery disease. Moreover, plaques with positive and negative remodeling were changed into those with intermediate remodeling by pitavastatin. Pitavastatin might induce not only plaque regression or stabilization, but also conformational normalization of vessel structure.

Effect of the Kv1.3 voltage-gated potassium channel blocker PAP-1 on the initiation and progress of atherosclerosis in a rat model

Acute coronary syndrome is a serious medical emergency. It occurs when an atherosclerotic plaque ruptures, leading to thrombus formation within a coronary artery. Previous studies have shown that T cells are involved in the initiation and progression of acute coronary syndrome. CD4(+)CD28(null) T lymphocytes increase in atherosclerotic plaque, and voltage-gated potassium channel Kv1.3 blockers can suppress the function of these cells in vitro by preventing exocytosis of their cytoplasmic granules. The purpose of this study was to investigate the effect of PAP-1, a small molecule voltage-gated potassium channel Kv1.3 blocker, on the development of atherosclerosis (AS) in a rat model and the potential mechanism for this effect. Plasma lipids, interferonγ, CRP, CD4(+)CD28(null) T cells, and perforin were increased and unstable atherosclerotic plaques developed in the rat model of AS. Blockade of the Kv1.3 potassium channel via PAP-1 administration decreased perforin levels and prevented plaque formation but had no effect on the other changes seen in this AS model. These findings suggest that the small molecule, voltage-gated potassium channel Kv1.3 blocker PAP-1 can suppress the development of AS in a rat model, most likely by inhibiting the exocytosis of cytoplasmic granules from CD4(+)CD28(null) T cells.

Impacts of age on coronary atherosclerosis and vascular response to statin therapy

Age is a well-established risk factor for cardiovascular disease. Recent trials using intravascular ultrasound (IVUS) have shown that lipid-lowering therapy with statins halts the progression or induces the regression of coronary artery plaques. However, impacts of age on coronary atherosclerosis and vascular response to statin therapy have not been fully evaluated. The effects of 8-month statin therapy on coronary atherosclerosis were evaluated using virtual histology-IVUS. IVUS data were analyzed from 119 patients who were divided into two groups according to age: elderly patients (≥65 years, n = 72) and non-elderly patients (<65 years, n = 47). No patients were taking statins or other lipid-lowering therapies at baseline. At baseline, external elastic membrane (EEM) volume (17.27 vs. 14.95 mm(3)/mm, p = 0.02) and plaque volume (9.49 vs. 8.11 mm(3)/mm, p = 0.03) in the elderly patients were significantly greater than in the non-elderly patients. The EEM volume (-2.4 %, p = 0.007) and plaque volume (-3.1 %, p = 0.007) after 8-month of statin therapy had significantly decreased in the non-elderly patients but not in the elderly patients. A significant positive correlation was observed between age and percentage change in plaque volume (r = 0.265, p = 0.004). A multivariate regression analysis showed that age was a significant predictor of the percentage change in plaque volume during statin therapy (β = 0.223, p = 0.02). Coronary atherosclerosis was more advanced and vascular responses to statin therapy were attenuated in the elderly patients compared to the non-elderly patients.

Characterization of the effect of serum bilirubin concentrations on coronary endothelial function via measurement of high-sensitivity C-reactive protein and high-density lipoprotein cholesterol

Bilirubin can prevent oxidation of low-density lipoprotein (LDL) and may protect against atherosclerosis and coronary heart disease (CHD). The goal of this study was to characterize the relationship between bilirubin and CHD through measurements of bilirubin concentration, coronary endothelial function, and markers of oxidative stress, inflammation, and lipid/glucose metabolism. The study population consisted of 141 patients without CHD who underwent Doppler flow study. Vascular reactivity was examined by intracoronary administration of papaverine, acetylcholine (ACh) and nitroglycerin using a Doppler guide wire. Serum bilirubin, high-sensitivity C-reactive protein (hsCRP), malondialdehyde-modified LDL, LDL cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting plasma glucose (FPG), and immunoreactive insulin were also measured. Homeostasis model assessment insulin resistance index and estimated glomerular filtration rate (eGFR) were calculated. Univariate analysis revealed that both percent change in coronary blood flow (CBF) and coronary artery diameter induced by ACh correlated positively with log-transformed bilirubin (r = 0.22, P < 0.05; r = 0.20, P < 0.05, respectively). Percent change in CBF in response to ACh correlated positively with eGFR (r = 0.24, P < 0.05) and correlated inversely with age, LDL-C, and log-transformed FPG (r = -0.24, P < 0.05; r = -0.17, P < 0.05, r = -0.22, P < 0.05, respectively). Multivariate analysis revealed that log-transformed bilirubin was the only independent predictor of percent change in CBF in response to ACh. Multivariate analysis revealed that log-transformed hsCRP and HDL-C were independent predictors of log-transformed bilirubin. These results suggest that a high level of bilirubin is associated with favorable coronary endothelial function, which may be mediated via the effect of bilirubin on inflammation and HDL-C.