Bunyamin Yavuz

Assessment of Endothelial Function in Alzheimer's Disease: Is Alzheimer's Disease a Vascular Disease?

OBJECTIVES: To compare endothelial function of people with Alzheimers disease (AD) with that of people without.

STATIN-D study: comparison of the influences of rosuvastatin and fluvastatin treatment on the levels of 25 hydroxyvitamin D.

Several studies have shown that low 25-hydroxyvitamin D levels are associated with higher risk of cardiovascular disease and an increase in 25-hydroxyvitamin D levels protects against cardiovascular disease. In this study, we aimed to compare the effects of rosuvastatin and fluvastatin on vitamin D metabolism. The study population consisted of 134 hyperlipidemic patients who had not previously been treated with lipid lowering medications. Patients were randomized in a 1:1 ratio to rosuvastatin 10 mg or fluvastatin 80 mg XL during the study. Lipid parameters, 25 hydroxyvitamin-D, and bone alkaline phosphatase (BALP) were obtained at baseline and after 8 weeks of rosuvastatin and fluvastatin treatment. Sixty-nine patients were administered rosuvastatin, and 65 patients fluvastatin. Total Cholesterol and LDL cholesterol decreased after 8 weeks of both rosuvastatin and fluvastatin treatments. Rosuvastatin was significantly more effective than fluvastatin on lowering total (P < 0.001) and LDL cholesterol (P < 0.001). There was a significant increase in 25-hydroxyvitamin D with rosuvastatin treatment (P < 0.001), whereas no significant change in 25-hydroxyvitamin D was observed with fluvastatin treatment. Mean BALP fell from 18.5 to 9.6 u/I (P < 0.001) with rosuvastatin and from 17.0 to 12.8 with fluvastatin (P= 0.004). There was no significant difference in BALP levels between rosuvastatin and fluvastatin treatment (P= 0.368). The present study demonstrated that 25-hydroxyvitamin D levels increased with rosuvastatin treatment; whereas fluvastatin treatment had no effect on 25-hydroxyvitamin D. This disparity could be related to the potency or the bioavailability of these two statins. Further studies are needed to clarify the relationship between statins and the vitamin D physiology.

Is psoriasis a pre-atherosclerotic disease? Increased insulin resistance and impaired endothelial function in patients with psoriasis

Background  Several studies have shown an association between psoriasis and atherosclerotic risk factors. In this study, we aimed to evaluate endothelial function by flow‐mediated dilation (FMD) and insulin resistance by Homeostasis model assessment‐insulin resistance (HOMA‐IR).

Aspirin Resistance Is Associated with Glycemic Control, the Dose of Aspirin, and Obesity in Type 2 Diabetes Mellitus

OBJECTIVE Aspirin resistance (AR) is increased in diabetic patients. It is not known whether glycemic control has effect on AR. DESIGN To test the hypothesis that glycemic control might have influence on aspirin resistance, we measured aspirin resistance and glycated hemoglobin (HbA1c) in diabetic patients. We also measured aspirin resistance in nondiabetic subjects and compared the results with the diabetic group. METHODS We examined AR in 108 diabetic patients and 67 nondiabetic subjects with impedance platelet aggregometry. Glycemic control was evaluated according to both fasting blood glucose (FBG) and HbA1c levels. RESULTS According to the analyses, diabetic patients had significantly higher AR (P < 0.01), alanine aminotransferase (P < 0.005), and body mass index (P < 0.05) and significantly lower high-density lipoprotein cholesterol (P < 0.005) levels compared with nondiabetic controls. A correlation analysis revealed that AR was positively correlated with body mass index (r = 0.190, P < 0.01), fasting blood glucose (r = 0.224, P < 0.001), and HbA1c levels (r = 0.297, P < .0001). Using low-dose aspirin (100 mg/d) was a risk factor for aspirin-resistant status in both diabetic patients (odds ratio 1.26, 95% confidence interval 1.01-1.58, P < 0.05) and overall study group (odds ratio 1.3, 95% confidence interval 1.08-1.56, P < 0.01). CONCLUSIONS These data suggest that glycemic control, obesity, and the dose of aspirin have influence on AR in diabetic subjects. Further studies with larger groups are needed to clarify the role of glycemic control on AR.

Plasma myeloperoxidase is related to the severity of coronary artery disease.

Objective — It has been shown that the main apolipoprotein of HDL, Apo A-1, is subjected to nitration by myeloperoxidase (MPO) and this oxidative modification renders HDL proatherogenic. The aim of this study is to evaluate the relationship between plasma MPO levels, and the severity of coronary artery disease. Methods and results — Forty-eight patients with coronary artery narrowing and 30 control subjects were enrolled in this study. The severity of the disease was assessed by Gensini scoring after angiography. MPO concentrations were determined by using an enzyme immunoassay. A subgroup of 30 patients underwent computerized tomography to determine the calcium load of coronary arteries. Plasma MPO levels were found significantly higher in patients with coronary artery disease than controls (4.27 [1.60 to 42.43] ng/mL vs. 2.93 [1.00 to 9.25] ng/mL, P = 0.002). MPO was positively correlated with both Gensini (r = 0.228, P = 0.044) and coronary calcium scores (r = 0.433, P = 0.017). The atherosclerotic burden was more strongly correlated with MPO levels than the traditional markers such as total cholesterol and HDL. Conclusions — We found that MPO levels were elevated in patients with coronary artery disease and this increase correlated with the extent and severity of atherosclerosis. Although it is a preliminary study with a relatively small group of subjects, we suggest that MPO might be evaluated as a new marker indicating the presence and severity of coronary artery disease.

The Metabolic Syndrome Is Associated with Complicated Gallstone Disease

BACKGROUND Gallstone disease (GD) is a common condition worldwide. Several studies demonstrated that the presence of gallstones is strongly associated with cardiovascular disease. The metabolic syndrome is a highly prevalent cardiovascular condition. OBJECTIVE To examine the relationship between complicated GD (CGD) and the metabolic syndrome or its components. METHODS Two hundred seventeen patients with gallstones were examined. All patients underwent biliary ultrasonography after a complete medical history and laboratory examination. Data collection for the diagnosis of metabolic syndrome included measurements of waist circumference, blood pressure and lipids, and biochemical tests. RESULTS Of the 217 patients examined, 115 patients (53%) had CGD and 102 patients (47%) had uncomplicated GD (UCGD). There was a significant difference between the number of patients with large gallstones in the CGD and UCGD groups (n=14 [12%] versus n=2 [2%], respectively; P=0.004). Metabolic syndrome, diabetes mellitus and large waist circumference were more prevalent in the CGD group than in the UCGD group. Homeostatic model assessment of insulin resistance scores were higher in the CGD group than in UCGD group (2.51 [95% CI 0.57 to 23.90] versus 2.20 [95% CI 0.09 to 8.87], respectively; P=0.032). Logistic regression analysis revealed that the presence of metabolic syndrome (OR 1.434; 95% CI 1.222 to 1.846, P=0.014), diabetes mellitus (OR 1.493; 95% CI 1.255 to 1.953; P=0.035) and large gallstones (OR 1.153; 95% CI 1.033 to 1.714; P=0.017) were independent predictors of CGD. CONCLUSION Results of the present study demonstrated that metabolic syndrome, diabetes and gallstone size were associated with CGD. Further prospective studies are needed to understand the clinical importance of this association.

Intra-left atrial mechanical delay detected by tissue Doppler echocardiography can be a useful marker for paroxysmal atrial fibrillation.

Objectives: There are some clinical and echocardiographic parameters to predict paroxysmal atrial fibrillation (PAF), but more sensitive predictors are needed. Tissue Doppler imaging may be a sensitive method for this purpose. Methods: Thirty‐four patients with PAF and 31 control subjects were studied. Time intervals from the beginning of P‐wave to beginning of A‐wave from lateral and septal mitral and right ventricular tricuspid annuli in tissue Doppler imaging were recorded. The differences between these intervals gave the mechanical delays between/within the corresponding atria. Results: There were no differences between groups with regard to age. PAF patients were found to have increased left atrial dimension and intra‐left atrial mechanical delay. Twenty‐five milliseconds was calculated as cutoff value to predict PAF. P‐wave dispersion was found to be increased in PAF. Conclusions: This study shows an increase in intra‐left atrial mechanical delay in PAF patients. This method can be used as an early marker to detect PAF.

Increased mean platelet volume in rheumatic mitral stenosis: A possible factor for thromboembolic events

BACKGROUNDS Systemic embolism is an important complication in patients with rheumatic mitral stenosis (RMS). The mean platelet volume (MPV) is considered a marker and determinant of platelet function since larger platelets are hemostatically more reactive than platelets of normal size, increasing the propensity to thrombosis. The aim of this study was to investigate MPV in patients with RMS and healthy control subjects. METHODS We selected 30 consecutive patients with RMS and 31 consecutive healthy age- and sex-matched control subjects. All subjects were in sinus rhythm. We measured MPV in a blood sample collected in EDTA. RESULTS Demographic data of the RMS (mean age: 39.5+/-9.9 years, 22 [71%] female) and control groups (mean age: 39.2+/-9.3 years, 20 [67%] female) were similar. The MPV was significantly higher in patients with RMS 8.8 (8.2-11.3) fl than control subjects 8.1 (7.1-9.3) (P<0.001). CONCLUSION Elevated MPV might be considered as a marker of increased thromboembolic risk in patients with RMS. We suggest that patients with high MPV values might benefit from antiplatelet therapy.

Serum elevated gamma glutamyltransferase levels may be a marker for oxidative stress in Alzheimer's disease.

BACKGROUND Gamma glutamyltransferase (GGT) plays a role in cellular glutathione uptake, which is an important element of antioxidant mechanisms. An increase in serum GGT is thought to be an early and sensitive marker of oxidative stress. Oxidative stress has a role in the pathogenesis of Alzheimers disease (AD). The aim of this study was to investigate the GGT levels in AD. METHOD In this cross-sectional study, 132 patients with AD (mean age: 74.1 +/- 7.4, female 62.9%) and 158 age- and gender-matched normal controls (mean age: 74.5 +/- 6.3, female 67.1%) were evaluated. For cognitive assessment, MMSE and clock drawing tests were performed; DSM-IV and NINCDS-ADRDA criteria were used. Serum GGT, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase concentrations were determined. RESULTS Median (min-max) GGT levels were 18 (9-70) in AD group and 17 (5-32) in normal controls. Mann-Whitney U test showed that GGT levels were significantly higher in AD patients (p = 0.012). Linear regression analysis revealed AD was an independent correlate of elevated GGT levels. Hypertension, diabetes mellitus, total cholesterol, and low density lipoprotein cholesterol were not associated with GGT levels. CONCLUSION GGT levels were increased significantly in AD patients. To evaluate the role of GGT as a marker of oxidative stress in AD, further studies are needed.

A Novel Echocardiographic Marker in Hypertensive Patients: Is Diastolic Dysfunction Associated With Atrial Electromechanical Abnormalities in Hypertension?

J Clin Hypertens (Greenwich). 2010;12:687–692. ©2010 Wiley Periodicals, Inc.