Low serum bilirubin concentration is a predictor of chronic kidney disease.

OBJECTIVE: Chronic kidney disease (CKD) is a worldwide public health problem. It is very important to identify the factors that affect CKD. Previous studies have reported that serum bilirubin concentration was positively correlated with renal function in a cross-sectional study. The aim of this study was to investigate the relationship between serum bilirubin concentration and the progression of CKD. METHODS: A cohort study was performed on a consecutive series of 2784 subjects without CKD, defined as estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m(2), at baseline. We analyzed the relationship between serum total bilirubin concentration at baseline and new-onset CKD in the general population. RESULTS: We followed the subjects for a median period of 7.7 years. There were 1157 females and 1627 males, and 231 females and 370 males developed CKD during this period. Multiple Cox regression analyses revealed that serum total bilirubin concentration (hazard ratio (HR) per 1.0 µmol/L increase 0.97 (95% CI 0.95-0.99), P = 0.0084) in addition to age, gamma-glutamyl transpeptidase (GGT), uric acid (UA), creatinine and medication for hypertension in men and serum total bilirubin concentration (HR per 1.0 µmol/L increase 0.96 (95% CI 0.93-1.00), P = 0.0309) in addition to age, GGT, alanine aminotransferase, UA, creatinine and medication for dyslipidemia in women were independent predictors of new-onset CKD, after adjusting for confounders. CONCLUSION: Our study demonstrated that serum total bilirubin concentration could be a novel risk factor for the progression of CKD, defined as eGFR <60 ml/min/1.73 m(2), in the general population.

Visit-to-visit variability in systolic blood pressure is a novel risk factor for the progression of coronary artery calcification.

Recent studies have suggested that variability in the systolic blood pressure (SBP) is a risk factor for cardiovascular disease (CVD). The aim of this study was to investigate the relationship between variability in the SBP and the progression of coronary artery calcification (CAC), which is a useful marker for CVD. We measured SBP in 164 consecutive patients at every visit over the course of a year and calculated the coefficient of variation and s.d. of the SBP. We performed a follow-up study using multislice computed tomography to assess the progression of the CAC score, the mean interval of which was 3.93 ± 1.36 years. We then evaluated the relationship between variability in the SBP and progression of the CAC score. The coefficient of variation for the SBP correlated positively with the progression of the CAC score (r=0.4382, P<0.0001). Multiple regression analysis demonstrated that the coefficient of variation of the SBP (ß=0.3826, P<0.0001) was independently associated with the progression of the CAC score. The visit-to-visit variability in SBP could be a novel risk factor for the progression of CAC.

Relationship between cardio-ankle vascular index (CAVI) and coronary artery calcification (CAC) in patients with type 2 diabetes mellitus.

Early detection of atherosclerosis is important for patients with type 2 diabetes mellitus because cardiovascular disease (CVD) is a main cause of death in these people. In this study, we investigated the relationship between an arterial stiffness parameter called cardio-ankle vascular index (CAVI) and coronary artery calcification (CAC). We performed a cross-sectional study in 371 type 2 diabetic patients with clinical suspicion of coronary heart disease (CHD). We evaluated the relationships between CAVI and CAC score determined by multislice computed tomography as well as major cardiovascular risk factors, including age, body mass index, hemoglobinA1c and the Framingham CHD risk score. CAVI was correlated with age (r = 0.301, p < 0.0001), uric acid (r = 0.236, p < 0.0001), estimated glomerular filtration rate (r = -0.145, p = 0.0166), CHD risk score (r = 0.327, p < 0.0001) and log (CAC + 1) (r = 0.303, p < 0.0001). The area under the receiver operating characteristic curve for CAVI was higher than that of CHD risk score in predicting CAC >0, CAC >100, CAC >400, or CAC >1000. CAVI is positively correlated with CAC, and is considered to be a useful method to detect CAC.

Eosinophil count is positively correlated with coronary artery calcification.

Recent studies suggested that allergic disorders and increased eosinophil count were associated with atherosclerosis. The purpose of this study was to assess the relationship between eosinophil count and coronary artery calcification (CAC). We performed a cross-sectional study in 1363 consecutive participants with clinical suspicion of coronary heart disease (CHD). We evaluated the relationships between CAC score determined by multislice CT and peripheral eosinophil count as well as major cardiovascular risk factors, including age, body mass index, smoking status, hypertension, dyslipidemia, diabetes mellitus (DM), high-sensitivity C-reactive protein and estimated glomerular filtration rate (eGFR). Sex (P=0.0004), hypertension (P=0.0002), dyslipidemia (P=0.0004) and DM (P=0.0061) were associated with log(CAC+1), respectively. Positive correlations were found between log(CAC+1), and age (r=0.325, P<0.0001) and eosinophil count (r=0.165, P<0.0001). Negative correlations were found between log(CAC+1) and eGFR (r=-0.166, P<0.0001). Multivariate linear regression analysis demonstrated that age (ß=0.314, P<0.0001), sex (ß=0.124, P<0.0001), hypertension (ß=0.084, P=0.0008), DM (ß=0.108, P<0.0001), eGFR (ß=-0.079, P=0.0021) and eosinophil count (ß=0.147, P<0.0001) were independent determinants of log(CAC+1). In conclusion, eosinophil count correlated positively with CAC in participants with clinical suspicion of CHD.

Very late stent thrombosis predicted by multislice computed tomography.

Although drug-eluting stents (DES) are rapidly replacing bare metal stents, there are increasing concerns regarding the potential for very late stent thrombosis after DES implantation. It is suggested that incomplete stent apposition (ISA) due to positive remodeling is strongly associated with this. We present a case of a 68-year-old male who developed very late stent thrombosis (VLST) 40 months after DES implantation. The ISA of the stented vessel had already been detected by multislice computed tomography (MSCT). MSCT could be a useful modality to detect VLST.

Low insulin level is associated with aortic stiffness.

Recent studies have demonstrated that hyperinsulinemia is a risk factor for cardiovascular disease. The aim of this study was to evaluate the relationship between serum insulin level and the cardio-ankle vascular index (CAVI), which was developed as a marker of arterial stiffness. We performed a cross-sectional study of 260 consecutive and nondiabetic subjects with clinical suspicion of coronary heart disease. We measured CAVI in all subjects. A standard 75-g oral glucose tolerance test was performed, and plasma glucose and serum insulin levels were measured in venous blood collected at 0, 30, 60 and 120 min after the test. Statistical analyses were conducted for four subgroups according to the insulin area under the concentration time curve (InsAUC). Mean CAVI and InsAUC were 8.7 and 109.5 µIUml(-1)h(-1), respectively. Unadjusted analysis demonstrated that the InsAUC quartiles were significantly associated with CAVI (P<0.0001), and the lowest InsAUC quartile (P=0.001) had a lower glucose AUC. Analysis of covariance demonstrated that the lowest InsAUC quartile had the highest CAVI, and, after adjusting for several coronary risk factors, the highest InsAUC quartile had a higher CAVI than the second and third InsAUC quartiles (P<0.0001). In conclusion, the lowest InsAUC quartile was related to CAVI, although the lowest InsAUC quartile maintained glucose homeostasis in this study population. Both hyperinsulinemia and low insulin level are independently associated with CAVI.

U-shaped relationship between insulin level and coronary artery calcification (CAC).

AIM: Recent studies have suggested that hyperinsulinemia is associated with high cardiovascular risk. The purpose of this study was to assess the relationship between the serum insulin level and coronary artery calcification (CAC). METHODS: We performed a cross-sectional study of 582 consecutive and nondiabetic participants with clinical suspicion of coronary heart disease, and assessed the CAC score determined by multislice computed tomography. A standard 75-g oral glucose tolerance test was performed and venous blood was collected at 0, 30, 60 and 120 min for the measurement of plasma glucose and serum insulin. Statistical analyses were conducted for 4 subgroups according to fasting insulin and insulin area under the concentration time curve (InsAUC). RESULTS: Mean log (CAC+1) and InsAUC were 1.6 and 109.1 µIU/mL, respectively. Unadjusted analysis demonstrated that the fasting insulin quartiles (p=0.0256) and InsAUC quartiles (p<0.0001) were significantly associated with log (CAC+1), and the lowest fasting insulin quartiles (p<0.0001) and the lowest InsAUC quartile (p=0.0006) had lower glucose AUC. Analysis of covariance demonstrated that the lowest InsAUC quartile had the highest log (CAC+1), and the highest InsAUC quartile had a higher log (CAC+1) than the second and third InsAUC quartiles, adjusted for several coronary risk factors (p<0.0001). CONCLUSION: The lowest InsAUC quartile was related to CAC, although the lowest InsAUC quartile maintained glucose homeostasis, in this study population. Not only hyperinsulinemia but also a low insulin level are independently associated with CAC.

Low serum bilirubin concentration is associated with coronary artery calcification (CAC).

BACKGROUND: Bilirubin is a potent antioxidant and previous studies have reported the relationship between low serum bilirubin concentration and atherosclerosis. The purpose of this study was to assess the correlation between serum bilirubin concentration and coronary artery calcification (CAC). METHODS: This study consisted of 637 participants and we evaluated the relationship between CAC score determined by multislice computed tomography and serum bilirubin concentration. RESULTS: An inverse correlation was found between serum bilirubin concentration and log(CAC+1) (r=-0.361, P<0.0001). Multiple regression analysis also demonstrated that age (beta=0.261, P=0.0125), systolic blood pressure (beta=0.153, P=0.0237), uric acid (beta=0.126, P=0.0441), estimated glomerular filtration rate (beta=-0.139, P=0.0416) and serum bilirubin concentration (beta=-0.281, P<0.0001) were independent determinants of log(CAC+1). An increment of 1 micromol/L in serum bilirubin concentration was associated with 14% decrease in the odds for CAC score > or =400 after adjustment for several risk factors. Both age and SBP were also positively associated with CAC score > or =400, but the odds ratio for CAC score > or =400 was greater for every 1 micromol/L increment in serum bilirubin concentration than for every 1-year increment in age and 1-mmHg increment in SBP. CONCLUSIONS: Low serum bilirubin concentration is associated with coronary artery calcification. Serum bilirubin concentration can be measured easily in the clinical laboratory and applied in medical practice, and low serum bilirubin concentration would be useful as a provisional new risk factor of CAC.

Evaluation of characteristics and degree of remodeling in coronary atherosclerotic lesions by 64-detector multislice computed tomography (MSCT).

BACKGROUND: Multislice computed tomography (MSCT) permits reliable imaging of not only the coronary artery lumen but also vessel wall. It is assumed that both lipid-rich plaques and those that display positive remodeling are more prone to rupture and erosion with subsequent coronary events. The purpose of this study was to assess the correlation between the characteristics of coronary arteries by MSCT and several measures of coronary heart disease (CHD) risk. METHODS: This study consisted of 424 consecutive participants who received MSCT and coronary angiography (CAG). We assessed coronary artery findings including coronary artery calcification (CAC), degree of remodeling and narrowing of lumen and characteristics including uric acid (UA) and high-sensitivity C-reactive protein (hs-CRP). Statistical analyses were conducted for four subgroups classified by the presence of significant stenosis and positive remodeling. RESULTS: Hs-CRP was 2.10+/-2.70mg/L in positive remodeling (+) and stenosis (+) group (PS), 1.05+/-0.97mg/L in positive remodeling (-) and stenosis (+) group (nPS), 0.94+/-0.88mg/L in positive remodeling (+) and stenosis (-) group (PnS) and 0.44+/-0.49mg/L in positive remodeling (-) and stenosis (-) group (nPnS). The results of logistic regression analysis showed that hs-CRP was higher in PS compared with the other groups (p<0.001) and higher in nPS and PnS compared with nPnS (p<0.05). CONCLUSIONS: Regardless of significant stenosis, positive remodeling by MSCT correlates to the increase of hs-CRP.

Evaluation of vulnerable coronary plaques and non-alcoholic fatty liver disease (NAFLD) by 64-detector multislice computed tomography (MSCT).

BACKGROUND: Multislice computed tomography (MSCT) permits direct visualization of not only coronary artery stenosis but also the characteristics of plaques in patients with coronary artery disease (CAD). Also, because of its potential to be a novel risk factor for cardiovascular disease, interest in non-alcoholic fatty liver disease (NAFLD) is increasing. METHODS AND RESULTS: Participants comprised 298 consecutive patients who received MSCT to diagnose CAD. Patients with an alcohol intake exceeding 20 g/day or with a history of known liver disease were excluded from the study. Liver steatosis and 4 coronary artery findings, including remodeling lesions, lipid core plaques, calcified plaques and narrowing of lumen, were assessed. Liver steatosis was evaluated by computed tomography density of the liver and spleen. In the study, NAFLD was defined as having a liver and spleen (L:S) ratio of <1.1. The L:S ratios of patients with remodeling lesions or lipid core plaques were significantly lower than those without. NAFLD was related significantly to those findings, but there was no correlation between calcified plaques, narrowing of lumen and L:S ratios. Adjusted odds ratio of NAFLD for remodeling lesions was 2.41 (95% confidence interval (CI), 1.24-4.67; p=0.009), and those for lipid core lesions was 2.29 (95% CI, 1.15-4.56; p=0.018). CONCLUSION: NAFLD is a novel risk factor for vulnerable plaques.