Sequentially based analysis versus image based analysis of Intima Media Thickness in common carotid arteries studies - Do major IMT studies underestimate the true relations for cardio- and cerebrovascular risk?

<p>Abstract</p> <p>Background</p> <p>Image-based B-mode ultrasound has gained popularity in major studies as a non-invasive method of measuring cardio- and cerebrovascular risk factors. However, none of the major studies appears to have paid sufficient attention to the variation in end diastolic wall process. By using sequentially based analyses (SBA) of Intima-Media Thickness (IMT), the general purpose of this study was to show that the current image based (ECG tracked) analysis (IBA) has some major variations and might underestimate the true relations for cardiovascular events and stroke for IMT measurement.</p> <p>Method</p> <p>The study group consisted of 2500 healthy male subjects aged between 35 to 55 years. 4 sequences (300 images) were analyzed per subject. 750,000 images were analysed throughout the course of this study.</p> <p>Results</p> <p>IBA showed significantly lower mean, maximal, and minimal values for IMT in CCA than for SBA. The correlation analysis between IBA and SBA with the cardio- and cerebrovascular risk factors showed a higher correlation of SBA for all risk factors. The Pearson coefficient was 0.81, p < 0.01, for SBA versus Framingham CHD risk level (FCRL) and 0.49, p = 0.01, for IBA versus FCRL.</p> <p>Conclusion</p> <p>IBA did not measure the true maximal values of the IMT in this study. Together with the correlation analysis, this indicates that IBA might underestimate the true relations for IMT and risk factors.</p

Incidence and determinants of mortality and cardiovascular events in diabetes mellitus: a meta-analysis

Patients with diabetes mellitus are at increased risk of developing atherosclerotic disease. The extent of this additional risk and its determinants are not well known, but this information is needed for sample-size estimations in intervention studies. Therefore, a meta-analysis of epidemiologic studies on this subject was performed. Medline was searched from 1966 onwards, including the reference lists of all relevant publications, A total of 27 prospective follow-up studies in the English language that allowed calculation of the unadjusted incidence of one of the predefined outcome events were included. The influence of age, sex, type of diabetes, duration of diabetes, year of study, HbA(1c), cholesterol level, blood pressure and smoking on these incidences was studied by means of univariate Poisson regression analysis. Overall total mortality was 2.9% per year (95% CI 2.8-3.0; 27 studies), and for death from all vascular causes was 1.4% per year (95% CI 1.3-1.4; 16 studies). Only two studies were found that reported on the incidence of the composite outcome 'event death from all vascular causes, non-fatal myocardial infarction, or non-fatal stroke'. In univariate analysis, age, year of study, total cholesterol and systolic blood pressure were positively related to total mortality and death from all vascular causes. After adjustment for age, or limiting the analyses to studies in patients with type 2 diabetes only (n = 11), these relationships remained statistically significant. In conclusion, the overall yearly total mortality in diabetes mellitus is 2.9% and for death from all vascular causes is 1.4%. There are few data on the incidence of composite cardiovascular outcome events

Angiographic distribution of lower extremity atherosclerosis in patients with and without diabetes

Aims To determine differences in the anatomic site of atherosclerosis in the lower extremity between patients with and patients without diabetes. Design Cross-sectional study of patients who underwent angiography of both legs because of symptoms of intermittent claudication, rest and/or night pain, ulceration or gangrene. Methods The angiographies of 37 patients with diabetes and 37 patients without diabetes, matched for age, sex and smoking behaviour, were evaluated using the Bollinger scoring system. Results The mean (SD) Bollinger score in the upper leg (from the abdominal aorta to and including the superficial femoral artery) was higher (P = 0.01) for patients without diabetes (35.3 (22.8)) than for patients with diabetes (23.3 (16.1)). In the lower leg (from the popliteal artery to the posterior tibial artery) patients with diabetes tended to have a higher score than patients without diabetes: 47.4 (34.2) and 37.6 (32.9), respectively (P = 0.22). Conclusion This angiographic study confirms the clinical notion that lower limb atherosclerosis in diabetes is more severe in distal segments of the lower extremity, while the proximal segments remain less attenuated compared with patients without diabetes

Effect of intensive lipid-lowering strategy on low-density lipoprotein particle size in patients with type 2 diabetes mellitus

A preponderance of small dense LDL particles is strongly associated with the occurrence of atherosclerotic disease. Although several studies have documented an increased prevalence of small dense LDL particles in diabetes mellitus no data are available to show the effect of lipid-lowering treatment upon the improvement of LDL particle size. In the present study we examined the effect of lipid-lowering treatment, following an intensive lipid-lowering strategy for 30 weeks pursuing ADA recommended target lipid levels, on LDL particle size in 50 type 2 diabetic patients with moderate hyperlipidemia. At week 0, 24 patients (48%) were characterized by small dense LDL phenotype pattern B. After the treatment period a shift towards normal LDL particle size was observed in 17 patients but seven patients (29%) showed the more atherogenic LDL subclass pattern B. After treatment, plasma HDL-cholesterol was significantly lower (P <0.05) in these patients compared to those who had LDL subclass pattern A. Multivariate regression analysis revealed VLDL-cholesterol or triglycerides and HDL(3)-cholesterol as independent determinants for LDL particle size. Change in HDL(2)-cholesterol was an independent determinant for change in LDL particle size. In conclusion, a strategy of intensive lipid-lowering, with the intention to reduce triglyceride levels below 1.7 mmol/l, may be insufficient to ensure improvement in LDL size in all patient