Role of Small Dense Low-density Lipoprotein Cholesterol in Cardiovascular Events in Patients with Coronary Artery Disease and Type 2 Diabetes Mellitus Receiving Statin Treatment.

AIM: There is little information on the relationships of serum small dense low-density lipoprotein cholesterol (sdLDL-C) levels and serum triglyceride (TG) levels with cardiovascular events in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (DM) who are receiving statins. The aim of this study was to evaluate the relationships of serum TG levels and sdLDL-C levels as residual risks for cardiovascular events in patients with CAD and type 2 DM who were being treated with statins. METHODS: The subjects were divided into four groups based on TG levels and sdLDL-C levels: sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, and sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL. During a median follow-up period of 1419 days, cardiovascular events occurred in 34 patients. RESULTS: The incidences of cardiovascular events were significantly higher in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL and in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL, but not in patients with sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, than in patients with sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL. CONCLUSIONS: Under the condition of treatment with statins, patients with CAD and type 2 DM who had sdLDL-C levels of ≥ 40.0 mg/dL had a high risk for cardiovascular events even though serum TG levels were controlled at ＜150 mg/dL.

Reduced reactive hyperemia of the brachial artery in diabetic patients assessed by repeated measurements: The FMD-J B study.

Type 2 diabetes mellitus (T2DM) is a major cause of microvascular dysfunction. However, its effect on blood flow patterns during ischemic demand has not been adequately elucidated. In this study, we investigated the hypothesis that microvascular dysfunction in patients with T2DM manifests as brachial reactive hyperemia (BRH), defined as the ratio of peak blood flow velocities in a brachial artery before and after forearm cuff occlusion. The study enrolled 943 subjects (men, n = 152 [T2DM] and n = 371 [non-T2DM]; women, n = 107 [T2DM] and n = 313 [non-T2DM], respectively) with no history of cardiovascular disease. Semiautomatic measurements were obtained three times at 1.5-year intervals to confirm the reproducibility of factors involved in BRH for each sex. An age-adjusted mixed model demonstrated attenuated BRH in the presence of T2DM in both men (p = 0.022) and women (p = 0.031) throughout the study period. Post hoc analysis showed that the estimated BRH was significantly attenuated in patients with T2DM regardless of sex, except at baseline in women. In multivariate regression analysis, T2DM was a negative predictor of BRH at every measurement in men. For women, BRH was more strongly associated with alcohol consumption. Repeated measurements analysis revealed that T2DM was associated with attenuated postocclusion reactive hyperemia.

Effect of Novel Stratified Lipid Risk by "LDL-Window" and Flow-Mediated Dilation on the Prognosis of Coronary Artery Disease Using the FMD-J Study A Data.

BACKGROUND: Elevated levels of triglyceride (TG) and non-high-density lipoprotein cholesterol (non-HDL-C) are regarded as a residual lipid risk in low-density lipoprotein cholesterol (LDL-C)-lowering therapy. This study investigated the association between lipid risk stratified by TG and non-HDL-C and the prognosis of patients with coronary artery disease (CAD), and the association between stratified lipid risk and flow-mediated dilatation (FMD) index.Methods and Results: The 624 CAD patients enrolled in flow-mediated dilation (FMD)-J study A were divided into 4 groups: low-risk group (n=413) with TG <150 mg/dL and non-HDL-C <170 mg/dL; hyper-TG group (n=180) with TG ≥150 mg/dL and non-HDL-C <170 mg/dL; hyper-non-HDL group (n=12) with TG <150 mg/dL and non-HDL-C ≥170 mg/dL; and high-risk group (n=19) with TG ≥150 mg/dL and non-HDL-C ≥170 mg/dL. Comparison of the groups showed the cumulative incidence of a 3-point major adverse cardiovascular event (MACE) was different and highest in the high-risk group in all the patients (P=0.009), and in patients with a FMD index ≥7.0% (P=0.021), but not in those with a FMD index <7.0%. Multivariable regression analysis showed that high lipid risk (P=0.019) and FMD <7.0% (P=0.040) were independently correlated with the incidence of a 3-point MACE. CONCLUSIONS: Novel stratification of lipid risk, simply using TG and non-HDL-C levels, combined with FMD measurement, is useful for predicting cardiovascular outcomes in patients with CAD.

Usefulness of the SAGE score to predict elevated values of brachial-ankle pulse wave velocity in Japanese subjects with hypertension.

The score based on the office systolic blood pressure, age, fasting blood glucose level, and estimated glomerular filtration rate (SAGE score) has been proposed as a useful marker to identify elevated values of carotid-femoral pulse wave velocity (PWV). The present cross-sectional study was conducted to examine whether the SAGE score is also a useful marker to identify subjects with elevated brachial-ankle PWV values in Japanese subjects with hypertension. We measured the brachial-ankle PWV and calculated the SAGE score in a total of 1019 employees of a Japanese company with hypertension and 817 subjects with hypertension derived from a multicenter study cohort. The analyses in this study were based on data from these two study groups as well as on a composite population of the two (n = 1836). The receiver operating characteristic curve analysis showed that the area under the curve to identify subjects with brachial-ankle PWV values of ≥1800 cm/s was over 0.70 in each of the three study groups. Even after adjustments, a SAGE score ≥7 had a significant odds ratio for identifying subjects with brachial-ankle PWV values ≥1800 cm/s in the 1836 study subjects from the composite occupational and multicenter study cohort (odds ratio = 2.1, 95% confidence interval = 1.4-3.0, P < 0.01). Thus, in Japanese subjects with hypertension, the SAGE score may be a useful marker for identifying subjects with elevated brachial-ankle PWV values.

Increased arterial stiffness and cardiovascular risk prediction in controlled hypertensive patients with coronary artery disease: post hoc analysis of FMD-J (Flow-mediated Dilation Japan) Study A.

The usefulness of brachial-ankle pulse wave velocity (baPWV), an index of arterial stiffness, is not fully known for the management of treated hypertensive patients with a history of coronary artery disease (CAD) who have blood pressure less than 130/80 mmHg, a recommended blood pressure target in the updated major hypertension guidelines. We analyzed data for 447 treated hypertensive patients with CAD enrolled in FMD-J Study A for assessment of the predictive value of baPWV for future cardiovascular events. The primary outcome was a composite of coronary events, stroke, heart failure, and sudden death. During a median follow-up period of 47.6 months, the primary outcome occurred in 64 patients. Blood pressure less than 130/80 mmHg was significantly associated with a lower risk of the composite outcome independent of other cardiovascular risk factors in treated hypertensive patients with CAD (hazard ratio, 0.59; 95% confidence interval (CI), 0.35-0.99; P = 0.04). In treated hypertensive patients with CAD who had blood pressure less than 130/80 mmHg, baPWV above the cutoff value of 1731 cm/s, derived from receiver-operator characteristic curve analysis for the composite outcome was significantly associated with a higher risk of the composite outcome independent of conventional risk factors (hazard ratio, 2.83; 95% CI, 1.02-7.91; P = 0.04). baPWV was an independent predictor of cardiovascular events in treated hypertensive patients with CAD who had blood pressure less than 130/80 mmHg, for whom measurement of baPWV is recommended for cardiovascular risk assessment.

Diagnostic Criteria of Flow-Mediated Vasodilation for Normal Endothelial Function and Nitroglycerin-Induced Vasodilation for Normal Vascular Smooth Muscle Function of the Brachial Artery.

Background Diagnostic criteria of flow-mediated vasodilation (FMD), an index of endothelial function, and nitroglycerin-induced vasodilation (NID), an index of vascular smooth muscle function, of the brachial artery have not been established. The purpose of this study was to propose diagnostic criteria of FMD and NID for normal endothelial function and normal vascular smooth muscle function. Methods and Results We investigated the cutoff values of FMD and NID in subjects with (risk group) and those without cardiovascular risk factors or cardiovascular diseases (no-risk group) in 7277 Japanese subjects (mean age 51.4±10.8 years) from the Flow-Mediated Dilation Japan study and the Flow-Mediated Dilatation Japan Registry study for analysis of the cutoff value of FMD and in 1764 Japanese subjects (62.2±16.1 years) from the registry of Hiroshima University Hospital for analysis of the cutoff value of NID. Receiver-operator characteristic curve analysis of FMD to discriminate subjects in the no-risk group from patients in the risk group showed that the optimal cutoff value of FMD to diagnose subjects in the no-risk group was 7.1%. Receiver-operator characteristic curve analysis of NID to discriminate subjects in the no-risk group from patients in the risk group showed that the optimal cutoff value of NID to diagnose subjects in the no-risk group was 15.6%. Conclusions We propose that the cutoff value for normal endothelial function assessed by FMD of the brachial artery is 7.1% and that the cutoff value for normal vascular smooth muscle function assessed by NID of the brachial artery is 15.6% in Japanese subjects. Clinical Trial Registration www.umin.ac.jp Unique identifiers: UMIN000012950, UMIN000012951, UMIN000012952, and UMIN000003409.

Brachial-Ankle Pulse Wave Velocity Versus Its Stiffness Index ß-Transformed Value as Risk Marker for Cardiovascular Disease.

Background The difference in the predictive ability of the brachial-ankle pulse wave velocity (baPWV) and its stiffness index ß-transformed value (ß-baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined. Methods and Results In study 1, a 7-year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for ß-baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3-year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar. Conclusions Stiffness index ß transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects.

Target of Triglycerides as Residual Risk for Cardiovascular Events in Patients With Coronary Artery Disease　- Post Hoc Analysis of the FMD-J Study A.

BACKGROUND: Circulating triglyceride (TG) levels are a current focus as a residual risk for cardiovascular (CV) events. We evaluated the relationship between circulating TG levels and future CV events in patients with coronary artery disease (CAD) who were treated with conventional therapy. Methods and Results: We analyzed data for 652 patients who were enrolled in the FMD-J Study A. We investigated the associations between serum TG levels and first major CV events (death from CV cause, nonfatal acute coronary syndrome (ACS), nonfatal stroke, and CAD) for a 3-year follow-up period. Patients were divided into 4 groups based on serum TG level: low-normal (<100 mg/dL), high-normal (100-149 mg/dL), borderline hypertriglyceridemia (150-199 mg/dL), and moderate hypertriglyceridemia (≥200 mg/dL). During a median follow-up period of 46.6 months, 14 patients died (9 from CV causes), 16 had nonfatal ACS, 6 had nonfatal stroke, and 54 had CAD. The Kaplan-Meier curves for first major CV event among the 4 groups were significantly different (P=0.04). After adjustment for various confounders, serum TG level ≥100 mg/dL were significantly associated with an increased risk of first major CV events compared with serum TG level <100 mg/dL. CONCLUSIONS: Serum TG level may be a surrogate marker for predicting CV events in patients with CAD.

Endothelial Dysfunction, Increased Arterial Stiffness, and Cardiovascular Risk Prediction in Patients With Coronary Artery Disease: FMD-J (Flow-Mediated Dilation Japan) Study A.

BACKGROUND: The usefulness of vascular function tests for management of patients with a history of coronary artery disease is not fully known. METHODS AND RESULTS: We measured flow-mediated vasodilation (FMD) and brachial-ankle pulse wave velocity (baPWV) in 462 patients with coronary artery disease for assessment of the predictive value of FMD and baPWV for future cardiovascular events in a prospective multicenter observational study. The first primary outcome was coronary events, and the second primary outcome was a composite of coronary events, stroke, heart failure, and sudden death. During a median follow-up period of 49.2 months, the first primary outcome occurred in 56 patients and the second primary outcome occurred in 66 patients. FMD above the cutoff value of 7.1%, derived from receiver-operator curve analyses for the first and second primary outcomes, was significantly associated with lower risk of the first (hazard ratio, 0.27; 95% confidence interval, 0.06-0.74; P=0.008) and second (hazard ratio, 0.32; 95% confidence interval, 0.09-0.79; P=0.01) primary outcomes. baPWV above the cutoff value of 1731 cm/s was significantly associated with higher risk of the first (hazard ratio, 1.86; 95% confidence interval, 1.01-3.44; P=0.04) and second (hazard ratio, 2.19; 95% confidence interval, 1.23-3.90; P=0.008) primary outcomes. Among 4 groups stratified according to the combination of cutoff values of FMD and baPWV, stepwise increases in the calculated risk ratio for the first and second primary outcomes were observed. CONCLUSIONS: In patients with coronary artery disease, both FMD and baPWV were significant predictors of cardiovascular events. The combination of FMD and baPWV provided further cardiovascular risk stratification. CLINICAL TRIAL REGISTRATION: URL: www.umin.ac.jp. Unique identifier: UMIN000012950.

Cross-sectional and longitudinal associations between serum uric acid and endothelial function in subjects with treated hypertension.

OBJECTIVES: The endothelial dysfunction-arterial stiffness-atherosclerosis continuum plays an important pathophysiological role in hypertension. The aim of this study was to investigate the cross-sectional association between serum uric acid (SUA) and vascular markers related to this continuum, and to assess the longitudinal association between SUA and endothelial function that represents the initial step of the continuum. METHODS: We evaluated the baseline associations between SUA levels and vascular markers that included flow-mediated vasodilatation (FMD), brachial-ankle pulse wave velocity (baPWV), and common carotid artery intima-media thickness (CCA-IMT) in 648 subjects receiving antihypertensive treatment. The longitudinal association between baseline SUA levels and FMD measured at 1.5 and 3 yr of follow-up was also investigated. RESULTS: At baseline, modest, but significant correlations were observed between SUA and FMD in females (r = -0.171), baPWV in males with SUA >368.78 µmol/L (r = -0.122) and in females with a SUA level ≤ 362.83 µmol/L (r = 0.217), mean CCA-IMT in females with a SUA level ≤ 333.09 µmol/L (r = 0.139), and max CCA-IMT in females with SUA level ≤ 333.09 µmol/L (r = 0.138). A longitudinal association between SUA and FMD was less observed in males. In females, the baseline SUA was associated significantly with FMD values at 1.5 yr (r = -0.211), and SUA levels >237.92 µmol/L were associated significantly and independently with FMD values at 3 yr (r = -0.166). CONCLUSIONS: Lower SUA levels were associated with better vascular markers of the continuum, especially in females. Furthermore, we observed a longitudinal association between SUA and endothelial function, suggesting SUA level may be a potential marker of the continuum in hypertension.

Three nights leg thermal therapy could improve sleep quality in patients with chronic heart failure.

Sleep quality is often impaired in patients with chronic heart failure (HF), which may worsen their quality of life and even prognosis. Leg thermal therapy (LTT), topical leg warming, has been shown to improve endothelial function, oxidative stress, and cardiac function in patients with HF. However, its short-term influence to sleep quality has not been evaluated in HF patients. Eighteen of 23 patients with stable HF received LTT (15 min of warming at 45 °C and 30 min of insulation) at bedtime for 3 consecutive nights and 5 patients served as control. Subjective sleep quality was evaluated by St. Mary's Hospital Sleep Questionnaire, Oguri-Shirakawa-Azumi Sleep Inventory, and Epworth sleepiness scale, and also objectively evaluated by polysomnography. LTT significantly improved subjective sleep quality indicated by depth of sleep (p < 0.01), sleep duration (p < 0.05), number of awaking (p < 0.01), nap duration (p < 0.01), sleep quality (p < 0.05), and sleep satisfaction (p < 0.05). It was also objectively affirmed by a slight but significant decrease of sleep stage N1 (p < 0.01), and increase in sleep stage N2 (p < 0.05). No significant changes occurred in the controls. Hence, the short-term LTT could improve subjective and objective sleep quality in patients with HF. LTT can be a complimentary therapy to improve sleep quality in these patients.

Brachial artery diameter as a marker for cardiovascular risk assessment: FMD-J study.

BACKGROUND AND AIMS: Baseline brachial artery (BBA) diameter has been reported to be a potential confounding factor of flow-mediated vasodilation (FMD). The purpose of this study was to evaluate the relationships between BBA diameter and cardiovascular risk factors and compare the diagnostic accuracy of BBA diameter in subjects without cardiovascular risk factors and patients with cardiovascular disease (CVD) with that of FMD. METHODS: We measured BBA diameter and FMD in 5695 male subjects. In addition, we retrospectively investigated the incidence of cardiovascular events using another population sample consisting of 440 male subjects, to compare the accuracy of BBA diameter with that of FMD in predicting cardiovascular events. RESULTS: BBA diameter and FMD significantly correlated with age, body mass index, systolic blood pressure, diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, and glucose as well as Framingham risk score. The prevalence of cardiovascular risk factors and CVD increased with the increase in BBA diameter and FMD. Area under the curve (AUC) value of the receiver operating characteristic (ROC) curve for BBA diameter to diagnose subjects without cardiovascular risk factors (0.59 vs. 0.62, p = 0.001) or patients with CVD (0.58 vs. 0.64, p < 0.001) was significantly lower than that for FMD. In the retrospective study, the AUC value of the ROC curve for BBA diameter to predict first major cardiovascular events was significantly lower than that of FMD (0.50 vs. 0.62, p = 0.03). CONCLUSIONS: In men, BBA diameter was inferior to FMD for assessment of cardiovascular risk.

Longitudinal association among endothelial function, arterial stiffness and subclinical organ damage in hypertension.

OBJECTIVES: To examine the longitudinal mutual association between endothelial dysfunction and arterial stiffness, and also to determine which of the two variables was more closely associated with the progression of subclinical organ damage. METHODS: The brachial-ankle pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), estimated glomerular filtration rate, microalbuminuria and flow-mediated vasodilatation of the brachial artery (FMD) were measured three times at 1.5-year intervals in 674 Japanese patients receiving antihypertensive treatment. RESULTS: The change of the baPWV during the study period was larger in the subjects with baseline FMD values in the lowest tertile as compared to those with baseline FMD values in the highest tertile. The change of the CIMT was smaller in the subjects with baseline baPWV values in the lowest tertile than in those with baseline baPWV values in the highest tertile. After the adjustment, the FMD value at the baseline was inversely associated with the baPWV at the end of the study period (beta=-0.07, p=0.01), although, the reverse association was not significant. The baPWV, but not the FMD value, at the baseline was associated with the CIMT (beta=0.06, p=0.04) measured at the end of the study period. CONCLUSIONS: In hypertension, endothelial dysfunction was associated with the progression of arterial stiffness, although the reverse association was not confirmed. The increased arterial stiffness rather than endothelial dysfunction may be more closely associated with the progression of atherosclerotic vascular damage, and the endothelial dysfunction-arterial stiffness-atherosclerosis continuum may be important in hypertension.

The effects of vildagliptin compared with metformin on vascular endothelial function and metabolic parameters: a randomized, controlled trial (Sapporo Athero-Incretin Study 3).

BACKGROUND: Dipeptidyl peptidase-4 (DPP-4) inhibitors may have protective effects in the early stage of atherosclerosis in patients with type 2 diabetes, although similar effects in advanced atherosclerosis were not shown in recent randomized placebo-controlled studies. Therefore, we investigated the efficacy of DPP-4 inhibitor on endothelial function and glycemic metabolism compared with high-dose metformin. METHODS: In this multicenter, open-labeled, prospective, randomized, parallel-group comparison study, patients with type 2 diabetes treated with low-dose metformin (500-750 mg/day) were enrolled and randomly assigned to a vildagliptin, a DPP-4 inhibitor, add-on group (Vilda) or a double dose of metformin group (high Met) for 12 weeks. Flow-mediated dilation (FMD) and serum metabolic markers were assessed before and after treatment. In addition, glycemic control and metabolic parameters were also assessed. RESULTS: Ninety-seven subjects (aged 58.7 ± 11.0 years; body mass index, 25.9 ± 4.4 kg/m2; HbA1c, 7.3 ± 0.5%; FMD, 5.8 ± 2.6%) were enrolled. Eight subjects dropped out by the end of the study. There were no significant differences between the two groups in baseline characteristics. After 12 weeks, HbA1c was significantly improved in the Vilda group compared with the high Met group (- 0.80 ± 0.38% vs. - 0.40 ± 0.47%, respectively; p < 0.01). However, there were no significant differences in FMD (- 0.51 [- 1.08-0.06]% vs. - 0.58 [- 1.20-0.04]%). Although the apolipoprotein B/apolipoprotein A1 ratio was significantly reduced in the Vilda group compared with baseline (0.66-0.62; p < 0.01), the change did not differ significantly between the two groups (- 0.04 vs. 0.00; p = 0.27). Adiponectin levels were significantly increased in the Vilda group compared with the high Met group (0.75 µg/mL vs. 0.01 µg/mL; p < 0.01). CONCLUSIONS: Regardless of glycemic improvement, combination therapy of vildagliptin and metformin did not affect endothelial function but may exert favorable effects on adipokine levels and lipid profile in patients with type 2 diabetes without advanced atherosclerosis.

Endothelial Function Is Impaired in Patients Receiving Antihypertensive Drug Treatment Regardless of Blood Pressure Level: FMD-J Study (Flow-Mediated Dilation Japan).

Hypertension is associated with endothelial dysfunction. Blood pressure significantly correlates with endothelial function in antihypertensive drug-naive subjects. The purpose of this study was to determine whether treatment status affects the relationship between blood pressure and endothelial function. We measured flow-mediated vasodilation (FMD) in 2297 subjects, including 1822 antihypertensive drug-naive subjects and 475 treated hypertensive patients. FMD significantly decreased in relation to increase in systolic blood pressure (8.2±3.1% in subjects with systolic blood pressure of <120 mm Hg, 7.5±2.8% for 120-129 mm Hg, 7.1±2.8% for 130-139 mm Hg, and 6.7±2.6% for ≥140 mm Hg; P<0.001). Systolic blood pressure was independently associated with FMD in untreated subjects. In contrast, there was no significant relationship between systolic blood pressure and FMD in treated hypertensive patients (4.6±3.1% in treated hypertensives with systolic blood pressure of <120 mm Hg, 4.8±2.7% for 120-129 mm Hg, 4.9±2.8% for 130-139 mm Hg, and 4.5±2.3% for ≥140 mm Hg; P=0.77). Propensity score matching analysis revealed that the prevalence of endothelial dysfunction defined as FMD of less than the division point for the lowest tertile, and the middle tertile of FMD was significantly higher in treated hypertensive patients than in untreated subjects in all systolic blood pressure categories. Endothelial function assessed by FMD was impaired regardless of the level of blood pressure achieved by antihypertensive drug treatment in hypertensive patients.

Association Between Waist-to-Height Ratio and Endothelial Dysfunction in Patients With Morbidity　- A Report From the FMD-J Study.

BACKGROUND: Waist circumference (WC), waist-to-height ratio (WHtR) and body mass index (BMI) are known as easy anthropometric markers of abnormal obesity and screening tools for predicting cardiovascular outcomes, but which indices are best is unclear. We therefore investigated the superiority and association between each index and low flow-mediated dilatation (FMD) as a surrogate marker for cardiovascular outcomes in patients with morbidity in a large Japanese prospective cohort.Methods and Results:A total of 1,645 Japanese patients who had coronary artery disease and hypertension or diabetes mellitus were enrolled, and 1,087 of them were analyzed. The high-WHtR group (≥0.5) showed greater morbidity and increased inflammation in association with atherosclerosis compared with the low-WHtR group. High WHtR and advanced age were identified as predictors of low FMD (odds ratio (OR) 1.39, 95% confidence interval (CI) 1.02-1.88, P=0.037 and OR 1.55, 95% CI 1.19-2.01, P=0.001, respectively). However, WC was not associated with that risk in either sex (male: OR 1.37, 95% CI 0.97-1.93, P=0.076; female: OR 1.08, 95% CI 0.68-1.73, P=0.74), and no association was evident between high BMI and low FMD (OR 0.92, 95% CI 0.71-1.19, P=0.54). CONCLUSIONS: WHtR offers a superior predictor of decreased FMD than other anthropometric indices, and progression of arteriosclerosis might be detected more sensitively. Further study is needed to investigate the relationship between cardiovascular mortality and WHtR.

A Randomized Controlled Trial Comparing the Effects of Sitagliptin and Glimepiride on Endothelial Function and Metabolic Parameters: Sapporo Athero-Incretin Study 1 (SAIS1).

OBJECTIVES: The DPP-4 inhibitors are incretin-related drugs that improve hyperglycemia in a glucose-dependent manner and have been reported to exert favorable effects on atherosclerosis. However, it has not been fully elucidated whether DPP-4 inhibitors are able to improve endothelial function in patients with type 2 diabetes. Therefore, we investigated the efficacy of sitagliptin, a DPP-4 inhibitor, on endothelial function and glycemic metabolism compared with that of the sulfonylurea glimepiride. MATERIALS AND METHODS: In this multicenter, prospective, randomized parallel-group comparison study, 103 outpatients with type 2 diabetes (aged 59.9 ± 9.9 years with HbA1c levels of 7.5 ± 0.4%) with dietary cure only and/or current metformin treatment were enrolled and randomly assigned to receive sitagliptin or glimepiride therapy once daily for 26 weeks. Flow-mediated dilation (FMD), a comprehensive panel of hemodynamic parameters (Task Force® Monitor), and serum metabolic markers were assessed before and after the treatment. RESULTS: During the study period, no statistically significant change in %FMD was seen in both groups (sitagliptin, 5.6 to 5.6%; glimepiride, 5.6 to 6.0%). Secretory units of islets in transplantation, TNF-α, adiponectin and biological antioxidant potential significantly improved in the sitagliptin group, and superoxide dismutase also tended to improve in the sitagliptin group, while improvements in HbA1c levels were similar between groups. Cardiac index, blood pressure and most other metabolic parameters were not different. CONCLUSIONS: Regardless of glycemic improvement, early sitagliptin therapy did not affect endothelial function but may provide favorable effects on beta-cell function and on inflammatory and oxidative stress in patients with type 2 diabetes without advanced atherosclerosis. TRIAL REGISTRATION: UMIN Clinical Trials Registry System UMIN 000004955.

A Comparison of the Effects of the GLP-1 Analogue Liraglutide and Insulin Glargine on Endothelial Function and Metabolic Parameters: A Randomized, Controlled Trial Sapporo Athero-Incretin Study 2 (SAIS2).

OBJECTIVES: GLP-1 improves hyperglycemia, and it has been reported to have favorable effects on atherosclerosis. However, it has not been fully elucidated whether GLP-1 is able to improve endothelial function in patients with type 2 diabetes. Therefore, we investigated the efficacy of the GLP-1 analogue, liraglutide on endothelial function and glycemic metabolism compared with insulin glargine therapy. MATERIALS AND METHODS: In this multicenter, prospective randomized parallel-group comparison study, 31 diabetic outpatients (aged 60.3 ± 10.3 years with HbA1c levels of 8.6 ± 0.8%) with current metformin and/or sulfonylurea treatment were enrolled and randomly assigned to receive liraglutide or glargine therapy once daily for 14 weeks. Flow mediated dilation (FMD), a comprehensive panel of hemodynamic parameters (Task Force Monitor), and serum metabolic markers were assessed before and after the treatment period. RESULTS: A greater reduction (worsening) in %FMD was observed in the glargine group, although this change was not statistically different from the liraglutide group (liraglutide; 5.7 to 5.4%, glargine 6.7 to 5.7%). The augmentation index, C-peptide index, derivatives of reactive oxygen metabolites and BMI were significantly improved in the liraglutide group. Central systolic blood pressure and NT-proBNP also tended to be improved in the liraglutide-treated group, while improvements in HbA1c levels were similar between groups. Cardiac index, blood pressure and most other metabolic parameters were not different. CONCLUSIONS: Regardless of glycemic improvement, early liraglutide therapy did not affect endothelial function but may provide favorable effects on beta-cell function and cardioprotection in type 2 diabetics without advanced atherosclerosis. TRIAL REGISTRATION: UMIN Clinical Trials Registry System as trial ID UMIN000005331.

Reliability of measurement of endothelial function across multiple institutions and establishment of reference values in Japanese.

AIMS: For the standardization of flow-mediated vasodilatation (FMD) assessment as a clinical tool, validation of its reliability across multiple institutions and the establishment of normal/reference values based on reliable data from multiple institutions are needed. METHODS AND RESULTS: In Study 1, assessment of FMD (scan recording and analysis) using an ultrasonographic semi-automatic measuring system (sFMD) was conducted at 18 participating institutions (sFMD-INST) (n = 981). All of the brachial arterial scans were also analyzed at a core laboratory (sFMD-COLB). After 111 subjects with inadequate sFMD recordings were excluded (n = 880), the correlation between the sFMD-INST and sFMD-COLB improved from R = 0.725 to R = 0.838 (p < 0.001). In Study 2, based on good-quality sFMD data obtained from 6660 subjects without cardiovascular disease (CVD) and 729 subjects with CVD from 27 institutions, reference values of sFMD are proposed by the Framingham risk score (FRS)-based risk categories and according to gender and age. The receiver-operating characteristic curve analysis revealed a significant power of sFMD values in reference ranges to discriminate between subjects with and without CVD (e.g., area under curve = 0.64 in the FRS-low risk group). CONCLUSIONS: When the analysis was limited to cases with clear sFMD recordings, the reliability of the sFMD assessment (scan and its analysis) conducted in individual institutions appeared to be acceptable. Reference sFMD values (lower cuff occlusion) for the Japanese population are proposed based on reliable data derived from multiple institutions, and the reference values may identify patients without advanced vascular damage.

Autonomic nervous activation triggered during induction of reactive hyperemia exerts a greater influence on the measured reactive hyperemia index by peripheral arterial tonometry than on flow-mediated vasodilatation of the brachial artery in patients with hypertension.

Flow-mediated vasodilatation of the brachial artery (FMD) and reactive hyperemia index (RHI) measured by peripheral arterial tonometry are known to be weakly associated with one another, but the mechanisms underlying this weak association remain to be clarified. We examined whether the autonomic nervous activation induced by the 5 min forearm clamping used to induce reactive hyperemia might exert any influence on the FMD and RHI in subjects with hypertension. In 115 subjects with hypertension (age 61±1 years), the FMD and RHI were measured simultaneously, and the heart rate variability (HRV) parameters (low-frequency component (LF), high-frequency component (HF), and the ratio (LF/HF) between the two) were calculated from the electrocardiographic recordings obtained before and after the start of forearm clamping. A multivariate linear regression analysis with adjustments for confounding variables demonstrated that the RHI, but not the FMD, was significantly associated with the percent change of the LF/HF associated with forearm clamping (beta=-0.204, P=0.043). In conclusion, autonomic nervous system activation, especially sympathetic activation, induced by 5-min forearm clamping utilized to provoke reactive hyperemia may significantly affect the RHI rather than FMD in subjects with hypertension.