Michiaki Miyamoto

Distinct association of serum FGF21 or adiponectin levels with clinical parameters in patients with type 2 diabetes

Fibroblast growth factor 21 (FGF21) has been identified as a novel metabolic regulator. This cross-sectional study was performed to clarify how serum FGF21 levels were associated with clinical parameters in Japanese subjects with type 2 diabetes (n=139). Anthropometric and blood biochemical parameters, uses of drugs for diabetes, hypertension and dyslipidemia were examined regarding associations with fasting serum FGF21 concentrations. FGF21 levels were 6-times higher in those subjects taking fibrates. However, a use of thiazolidinediones did not affect serum FGF21 levels while it induced higher serum adiponectin levels. In univariate analyses, FGF21 levels showed associations with a use of fibrates, triglyceride levels, creatinine levels, waist circumference, and BMI. Multiple regression analyses adjusted for age, gender and BMI showed that a use of fibrates, triglyceride levels and creatinine levels were strong contributors to serum FGF21 levels. In contrast, a use of thiazolidinediones, HDL-cholesterol levels and fasting insulin levels were strong contributors to serum adiponectin levels. This study revealed that serum FGF21 levels were biochemical indicators correlating to a set of essential metabolic parameters, which was distinct from that correlating to serum adiponectin levels in subjects with type 2 diabetes.

Relationship between Reactive Oxygen Metabolites and Carotid Intima-Media Thickness in Subjects with Hypercholesterolemia

Objective: It was the aim of this study to investigate whether there is any relationship between oxidative stress, as assessed by the diacron reactive oxygen metabolite (d-ROM) test, and carotid atherosclerosis among hypercholesterolemic patients. Subjects and Methods: A well-defined group of patients with type II hypercholesterolemia (n = 81, mean age 59 years) was studied to observe the correlation between the levels of serum d-ROMs and carotid artery intima-media thickness (IMT) using B-mode ultrasound, in relation to the traditional atherosclerotic risk factors (age, sex, smoking, body mass index, blood pressure, glucose and lipid panels). Results: The mean level in low-density lipoprotein cholesterol (LDL-C) in this population was 4.45 mmol/l, d-ROMs were 323.2 Carr U, and IMT was 0.91 mm. A multiple regression analysis revealed a positive and significant correlation between IMT and d-ROMs (β = 0.27, p < 0.05), along with age and LDL-C. Conclusion: These results indicate that the increased oxidative stress levels using the d-ROM test, independent of aging and increased LDL-C levels, may be associated with carotid atherosclerosis even in hypercholesterolemic patients.

The effect of antihypertensive drugs on endothelial function as assessed by flow-mediated vasodilation in hypertensive patients.

Endothelial dysfunction is found in hypertensive patients and may serve as a prognostic marker of future cardiovascular events. Endothelial function can be assessed noninvasively by flow-mediated vasodilation (FMD). The goal of this paper is to summarize comprehensively the clinical trials that investigated the effects of antihypertensive drugs on endothelial function assessed by FMD in hypertensive patients. A PubMed-based search found 38 clinical trial papers published from January 1999 to June 2011. Significant improvement of FMD after antihypertensive treatment was shown in 43 of 71 interventions (among 38 clinical trial papers). Angiotensin II receptor blockers and angiotensin converting enzyme inhibitors appeared to improve FMD more than other drug types. Antihypertensive treatment can improve endothelial dysfunction when assessed by FMD, although there are conflicting data that require further research.

Degradation of ultrasound probes caused by disinfection with alcohol.

The aim of this study was to clarify the degree of degradation of ultrasonic probes that results from their disinfection with alcohol. No defect in the ultrasound beams was found in any of the probes, but a significant decrease of the brightness was found after a certain period of use of the linear-type probe. Disinfection with alcohol may degrade ultrasound probes despite its high degree of effectiveness in preventing iatrogenic bacterial transmission.

Clinical Significance of the Cardio-Ankle Vascular Index (CAVI) in Hypertension

Increased blood pressure and hypertension are a major atherosclerotic risk factor. Arterial stiffness is recognized to be reflective to the atherosclerotic states. The pulse wave velocity (PWV) is a noninvasive, simple, easy and reproducible index that can be used to assess arterial stiffness in association with blood pressure. The cardio-ankle vascular index (CAVI) has recently been developed to evaluate arterial stiffness similarly to PWV, but theoretically, this index is less influenced by blood pressure. There have been several clinical reports on the use of the CAVI in patients with hypertension. The CAVI levels are reported to be significantly and positively correlated with the ultrasonographical atherosclerotic parameters of carotid arteries, as a surrogate marker of atherosclerotic events, in hypertensive patients. Intervention studies of anti-hypertensive therapy using CAVI have shown that candesartan, olmesartan and efonidipine can improve the CAVI levels. These results suggest that the CAVI is clinically helpful for the assessment of atherosclerotic risk and the management with drug treatment in patients with hypertension. However, compared with PWV, there is not much evidence of using CAVI in a clinical setting; future research is therefore necessary.

Influence of ezetimibe monotherapy on ischemia-modified albumin levels in hypercholesterolemic patients.

Ischemia-modified albumin (IMA) is considered to be a novel biochemical marker for ischemic and atherosclerotic conditions. This study aimed to investigate the influence of ezetimibe monotherapy on circulating IMA levels in hypercholesterolemic patients. A total of 31 patients (mean age 65.7 years) received 10 mg of ezetimibe daily during a 12-week treatment period. The levels of low-density lipoprotein cholesterol and IMA were significantly reduced after ezetimibe treatment. The adjusted regression analyses revealed that the changes in the IMA levels were not significantly correlated with those of the other atherosclerotic risk markers, such as body mass index, blood pressure, glucose and lipid panels. The significant reduction of the IMA levels following ezetimibe treatment, which was independent of the reduction of low-density lipoprotein cholesterol levels, suggests that ezetimibe may improve the oxidative stress burden in hypercholesterolemic patients.

The Relationship between Urinary 8-Hydroxydeoxyguanosine and Metabolic Risk Factors in Asymptomatic Subjects

Objective: The aim of this study was to investigate the relationship between metabolic risk factors and oxidative stress using urinary 8-hydroxydeoxyguanosine (8-OHdG), a recently utilized biological marker, in asymptomatic subjects. Methods: Ninety subjects (males/females = 30/60; mean age = 52 years), who were nonsmoking, nondiabetic and not on any medicine, were enrolled in the study. The body mass index, blood pressure, total cholesterol, triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and glucose as well as urinary 8-OHdG and creatinine were measured. Results: The median level of 8-OHdG was 9.3 ng/mg creatinine (interquartile range: 5.8–23.2). TG (Pearson’s correlation: r = 0.262, p = 0.013) and HDL-C (r = –0.259, p = 0.014) showed a significant correlation with 8-OHdG. A multiple linear regression analysis adjusted for all the variables revealed that only TG had an independently significant and positive correlation with 8-OHdG (β = 0.231, p = 0.046). Conclusion: The data in this population suggest that, among metabolic risk factors, hypertriglyceridemia may be weakly but significantly associated with hyperoxidative stress as assessed by 8-OHdG.

The Relationship Between Serum C-Reactive Protein and Daily Physical Activity in Japanese Hypertensive Patients

Hypertension (HT) and C-reactive protein (CRP) are risk factors of cardiovascular diseases (CVD). The current studys purpose was to investigate the relationship between serum CRP levels and daily lifestyles, including physical activity, in Japanese HT patients. Lifestyle factors, blood pressure (BP), blood cholesterol, glucose, and CRP were measured in a total of 312 HT patients (153 men//159 women, mean age: 62.6 y). Women with physical activity of ≥ 1 time//week showed significantly lower CRP levels than those without it (p < 0.05). The data suggest that regular physical activity could reduce the CRP levels in HT patients, thereby maybe preventing CVD.

Current smoking status may be associated with overt albuminuria in female patients with type 1 diabetes mellitus: a cross-sectional study

BackgroundThere are very few clinical reports that have compared the association between cigarette smoking and microangiopathy in Asian patients with type 1 diabetes mellitus (T1DM). The objective of this study was to assess the relationships between urinary protein concentrations and smoking and gender-based risk factors among patients with T1DM.MethodsA cross-sectional study of 259 patients with T1DM (men/women = 90/169; mean age, 50.7 years) who visited our hospital for more than 1 year between October 2010 and April 2011 was conducted. Participants completed a questionnaire about their smoking habits. Patient characteristics included gender, age, body mass index, blood pressure, hemoglobin A1c, lipid parameters, and microangiopathy. Diabetic nephropathy (DN) was categorized as normoalbuminuria (NA), microalbuminuria (MA), or overt albuminuria (OA) on the basis of the following urinary albumin/creatinine ratio (ACR) levels: NA, ACR levels less than 30 mg/g creatinine (Cr); MA, ACR levels between 30 and 299 mg/g Cr; and OA, ACR levels over 300 mg/g Cr.ResultsThe percentages of current nonsmokers and current smokers with T1DM were 73.0% (n = 189) and 27.0% (n = 70), respectively. In addition, the percentage of males was higher than that of females (52.2% versus 13.6%) in the current smoking population. The percentage of DN was 61.8% (n = 160) in patients with NA, 21.6% (n = 56) in patients with MA, and 16.6% (n = 43) in patients with OA. The percentage of males among OA patients was also higher than that of females (24.4% versus 12.4%). However, current smoking status was associated with OA in females with T1DM only [unadjusted odds ratio (OR), 4.13; 95% confidence interval (CI), 1.45–11.73, P < 0.01; multivariate-adjusted OR, 5.41; 95% CI, 1.69–17.30, P < 0.01].ConclusionsBased on our results in this cross-sectional study of Asian patients with T1DM, smoking might be a risk factor for OA among female patients. Further research is needed of these gender-specific results.

Cardio-Ankle Vascular Index and Indices of Diabetic Polyneuropathy in Patients with Type 2 Diabetes

The cardio-ankle vascular index (CAVI) is used to test vascular function and is an arterial stiffness marker and potential predictor of cardiovascular events. This study aimed to analyze the relation between objective indices of diabetic polyneuropathy (DPN) and the CAVI. One hundred sixty-six patients with type 2 diabetes mellitus were included in this study. We used nerve conduction studies (NCSs) and the coefficient of variation of the R-R interval to evaluate DPN. We estimated arteriosclerosis by the CAVI. Simple and multiple linear regression analyses were performed between neuropathy indices and the CAVI. In univariate analysis, the CAVI showed significant associations with sural sensory nerve conduction velocity and median F-wave conduction velocity. Multiple linear regression analysis for the CAVI showed that sural nerve conduction velocity and median F-wave conduction velocity were significant explanatory variables second only to age. In multiple linear regression analysis for sural nerve conduction velocity among neuropathy indices, the CAVI remained the most significant explanatory variable. In multiple linear regression analysis for median nerve F-wave conduction velocity among neuropathy indices, the CAVI remained the second most significant explanatory variable following HbA1c. These results suggest a close relationship between macroangiopathy and DPN.