Associations of methylenetetrahydrofolate reductase C677T polymorphism with markers of subclinical atherosclerosis: The Cardiovascular Risk in Young Finns Study

Objective. To study whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism or serum homocysteine concentration is associated with carotid artery intima media thickness (IMT), carotid artery compliance (CAC) or brachial artery flow mediated dilatation (FMD) in a healthy Finnish adult population. Methods. Cross‐sectional data obtained in 2001 for the Cardiovascular Risk in Young Finns Study were used. Carotid artery IMT, CAC and brachial FMD were measured by ultrasound and serum homocysteine concentrations using a commercial immunoassay kit. We studied 1,440 subjects (aged 24–39 years). Genotyping was performed using the 5′ nuclease TaqMan assay. Results. Homocysteine values differed between genotypes in women and men (ANOVA, p<0.001 for both sex groups): the genotype raised values in the order of CC, CT, TT. There was a significant difference in CAC values between the MTHFR genotypes in men (ANOVA, p = 0.008), and the CC genotype had the lowest values. In multivariate linear regression analysis adjusted for other major coronary risk factors (e.g. age, smoking, body mass index, systolic blood pressure, C‐reactive protein), the association remained significant (R² = 25.8?%, beta = 0.091; p = 0.02). Homocysteine level was directly associated with CAC in the whole population (R² = 18.0?%, beta = 0.012; p = 0.014) and in women (R² = 9.3%, beta = 0.02; p = 0.013), but not in men (R² = 15.2?%, beta = 0.004; p = 0.444). We found no association between homocysteine level or the MTHFR polymorphism and carotid IMT or brachial artery FMD. Conclusions. The findings suggest that the MTHFR polymorphism does not influence IMT or FMD, but that the T allele may have an effect on CAC in men.     

Relationship of serum uric acid to measures of endothelial function and atherosclerosis in healthy adults

Although uric acid (UA) is considered as an antioxidant, the relationship between serum UA levels and cardiovascular diseases is not clear yet. Higher brachial artery resting diameter (BD), impaired brachial artery flow-mediated dilatation (FMD), increased carotid intima-media thickness (IMT), decreased aortic distensibility (AoD), and increased aortic stiffness index (AoSI) and elastic modulus (AoEM) are predictors for development and/or progression of atherosclerosis. In this study, BD, FMD, carotid IMT, AoD, AoSI and AoEM were studied in healthy subjects with UA concentrations in physiological range. One hundred 24 healthy volunteers between 26 and 55 years of age were included in this study. Each subject had a serum UA levels in normal range. Carotid IMT, BD and brachial FMD were measured by means of high-resolution vascular ultrasound. AoD, AoSI, AoEM were examined by transthoracic echocardiography. Endothelium-dependent dilatation (EDD) was assessed by establishing reactive hyperemia and endothelium-independent dilatation (EID) was determined by using sublingual isosorbide dinitrate. Although carotid IMT and EDD were significantly correlated with UA concentrations (r = 0.346, p < 0.0001; r = -0.255, p < 0.05, respectively), EID measurements were not significantly correlated with serum UA concentrations (r = - 0.105, p > 0.05). In addition, AoSI and AoEM were significantly correlated with serum UA levels (r = 0.368, p < 0.0001; r = -0.366, p < 0.0001, respectively), and there was a significant inverse correlation between AoD and serum UA concentrations (r = -0.366, p < 0.0001). Furthermore, in multivariate analysis, we found that serum UA concentrations were correlated with increased carotid IMT, reduced FMD and increased aortic stiffness independent of other cardiovascular risk factor (beta = 256, p = 0.002; beta = -193, p = 0.03; beta = 0.295, p < 0.0001, respectively). In healthy subjects, increased serum UA concentrations, even in physiological range, are a risk factor for increased carotid IMT, reduced FMD and increased aortic stiffness independent of other cardiovascular risk factor, and other factors related to the metabolic syndrome.     

Brachial artery diameter is related to cardiovascular risk factors and intima-media thickness

Background  Previous reports showed inconsistent results about the potential role of flow-mediated dilatation (FMD) in cardiovascular(CV) risk prediction. Few data are available about the role of nitroglycerin-mediated dilatation (NMD), but recently, brachial artery diameter(BAD) appeared to have predictive value in CV risk prediction.We determined the relation of FMD, BAD and NMD with known CV risk factors and intima-media thickness (IMT), a well-established surrogate marker of atherosclerosis, in a community-based population, the Nijmegen Biomedical Study (NBS).
Materials and methods  FMD, BAD and NMD were measured in the brachial, and IMT in the common carotid artery ultrasononically in 337 participants, aged 50–70 years. Traditional clinical and biochemical parameters were determined.
Results  Both FMD and NMD were not correlated with most CV risk factors or prevalent CVD. However, both IMT and BAD did show significant correlations with CV risk factors. In accordance, both IMT and BAD were significantly correlated with prevalent CVD ( r  = 0·62 and r  = −0·37, respectively) . Furthermore, FMD was not correlated with IMT and did hardly ( R ² = 1·1%) improve the prediction of IMT by CV risk factors in regression analysis. However, both BAD and NMD did correlate with IMT ( r  = −0·29 and r  = 0·25, respectively).
Conclusion  In our study, FMD and NMD were not related to known CV risk factors and prevalent CVD, and FMD was not correlated with IMT, a surrogate marker of atherosclerosis. Most intriguingly, BAD was significantly correlated with some CV risk factors, prevalent CVD and IMT. So, BAD is a potential valuable tool in CV risk prediction in middle-aged low-risk populations, whereas FMD is not.     

Associations of methylenetetrahydrofolate reductase C677T polymorphism with markers of subclinical atherosclerosis: the Cardiovascular Risk in Young Finns Study

OBJECTIVE: To study whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism or serum homocysteine concentration is associated with carotid artery intima media thickness (IMT), carotid artery compliance (CAC) or brachial artery flow mediated dilatation (FMD) in a healthy Finnish adult population. METHODS: Cross-sectional data obtained in 2001 for the Cardiovascular Risk in Young Finns Study were used. Carotid artery IMT, CAC and brachial FMD were measured by ultrasound and serum homocysteine concentrations using a commercial immunoassay kit. We studied 1,440 subjects (aged 24-39 years). Genotyping was performed using the 5' nuclease TaqMan assay. RESULTS: Homocysteine values differed between genotypes in women and men (ANOVA, p<0.001 for both sex groups): the genotype raised values in the order of CC, CT, TT. There was a significant difference in CAC values between the MTHFR genotypes in men (ANOVA, p = 0.008), and the CC genotype had the lowest values. In multivariate linear regression analysis adjusted for other major coronary risk factors (e.g. age, smoking, body mass index, systolic blood pressure, C-reactive protein), the association remained significant (R (2) = 25.8 %, beta = 0.091; p = 0.02). Homocysteine level was directly associated with CAC in the whole population (R (2) = 18.0 %, beta = 0.012; p = 0.014) and in women (R (2) = 9.3%, beta = 0.02; p = 0.013), but not in men (R (2) = 15.2 %, beta = 0.004; p = 0.444). We found no association between homocysteine level or the MTHFR polymorphism and carotid IMT or brachial artery FMD. CONCLUSIONS: The findings suggest that the MTHFR polymorphism does not influence IMT or FMD, but that the T allele may have an effect on CAC in men.     

The relationship of carotid three-dimensional ultrasound vessel wall volume with age and sex: comparison to carotid intima-media thickness

The relationship of three-dimensional ultrasound (3DUS)-derived carotid vessel wall volume (VWV) was evaluated with respect to age and sex. B-mode and 3DUS images were acquired for 316 subjects from diverse groups including obese primary prevention, diabetic nephropathy, renal transplant and rheumatoid arthritis populations. The relationship for intima-media thickness (IMT) and VWV with age and sex were determined using Pearson-product-moment correlations. Mean IMT (r = 0.18, p = 0.001) and VWV (r = 0.24, p < 0.01) correlated modestly with age. There were modest correlations in males (IMT, r = 0.19, p = 0.003; VWV, r = 0.34, p < 0.001) and in females for IMT and age (r = 0.30, p = 0.007) but not between 3DUS VWV and age in females (r = 0.10, p = 0.4). Significant associations between plaque and VWV (r = 0.36, p = 0.001) but not IMT suggest different correlations in females that may be attributed to plaque.     

A methodological study of arterial wall function using ultrasound technique

We aimed to establish reference values for three important properties of the arterial wall using a conventional ultrasound scanner. We measured: (1) intima–media thickness (IMT) of the carotid arteries with the internal trace function of the ultrasound system; (2) wall stiffness by pulsatile diameter changes in the right common carotid artery assessed by M-mode; and (3) endothelial function expressed as flow-mediated dilatation (FMD) of the brachial artery. IMT and wall stiffness measurements and reproducibility were compared with those obtained by external analysing systems. All variables were obtained in healthy subjects (n = 20), 29–53 years old. IMT increased with age (P<0·01). There was no difference in IMT between men and women. The inter-operator variability for measuring IMT was 6–9%. The same order of reproducibility was obtained with an external PC-based analysing system. Regarding wall stiffness, no correlation was found with age, nor any difference between men and women. A low intra-operator variability (CV < 10%) was found for measurements of wall stiffness with both M-mode and an external wall tracking system. FMD of the brachial artery diminished with age (P<0·01). There was a relation between FMD and brachial artery size (P<0·01) and, therefore, as men have larger arterial diameters (P<0·01), smaller FMD in men. We conclude that it is possible to characterize arterial wall function non-invasively in an adequately reproducible manner using a conventional ultrasound system in healthy middle-aged men and women.     

Evaluation Of Atherosclerosis Severity Based On Carotid Artery Intima-Media Thickness Changes: A New Diagnostic Criterion

This study aimed to identify instant intima-media thickness changes (ΔIMT) in the common carotid artery (CCA) during cardiac cycle in order to assess atherosclerosis progression. Using a computerized semi-automated method, instant IMT changes were extracted in the two walls of the left CCA (240 consecutive patients) using B-mode ultrasound images. We found that CCA ΔIMT increased from 8 ± 4% of IMT_max in the controls to 15 ± 6% of IMT_max in the severe stenosis group. According to the multiple ordinal regression analysis, ΔIMT was associated with the severity of carotid artery stenosis (odds ratio [OR], 4.95; p < 0.001), independent of sex (OR, 1.11; p = 0.04), age (OR, 1.14; p < 0.001), body mass index; OR, 1.13; p = 0.036), hypertension (OR, 2.04; p < 0.001), diabetes (OR, 1.38; p = 0.045) and hyperlipidemia (OR, 1.54; p = 0.002). We concluded that increment of CCA ΔIMT during the cardiac cycle was strongly and independently associated with severity of carotid artery stenosis or atherosclerosis progression.     

Serial assessment of arterial structure and function in patients with coarctation of the aorta undergoing stenting

Stenting for CoA has become an acceptable treatment modality in the last 20 years. However little is known about arterial changes after this procedure. To assess arterial structure and function including peripheral reactivity and stiffness and intima-media thickness (IMT) pre and post stenting for coarctation of the aorta (CoA). Twenty-one patients [median age: 15 years (8–39)] were studied at baseline, 1 day, 6 months and 1 year after stenting. Twenty-one healthy subjects (1:1 matched) were used as controls. Left ventricular (LV) mass, ejection fraction, flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) of left brachial artery, common carotid (CC) and right subclavian artery (RSCA) IMT and pulse wave velocity (PWV) were assessed by echocardiography and vascular ultrasound. CoA patients had higher LV indexed mass (p < 0.0001), impaired FMD (p < 0.0001) and NMD (p < 0.0001), increased PWV (p < 0.0001), carotid and RSCA IMT (both p < 0.0001). All procedures were successful and resulted in significant gradient reduction (p < 0.001). One year after stenting there was improvement in LV function (p = 0.034) and although there was significant reduction of LV mass (103.29 ± 24.77 vs. 74.39 ± 22.07 g/m², p < 0.0001) values did not normalize. There was no significant change in FMD, NMD, PWV and CC or RSCA IMT. In patients with CoA, arterial reactivity is impaired and LV mass, arterial stiffness and thickness are increased. Although stenting is successful to relieve the obstruction resulting in better LV function and mass reduction, arterial structure and function remains abnormal after 1 year of follow-up.     

Investigation of early atherosclerotic changes in acromegalic patients

Background: Functional and morphological changes of endothelium were risk factors for mortality attributed to atherosclerosis. Studies investigating early atherosclerotic alterations and the effect of the treatment of acromegaly on these alterations gave conflicting results. Objective: Surrogate markers of early atherosclerotic changes, i.e. brachial artery flow‐mediated dilation (FMD) and carotid artery intima‐media‐thickness (IMT) in active and inactive acromegalic patients were compared with control subjects matched to patients for age, sex and cardiovascular risk factors to find out the direct effects of growth hormone (GH)/insulin‐like growth factor‐1 excess. Methods: In 14 active acromegalics and their 14 matched controls, 14 inactive acromegalics and their 14 matched controls, carotid artery IMT and FMD of brachial artery were measured. Inactive acromegalics were in remission for at least 1 year. Results: Active acromegalics had higher IMT than matched controls and inactive acromegalics (0.85 ± 0.20 mm, 0.64 ± 1.77 mm, 0.66 ± 0.20 mm respectively; p < 0.005, p < 0.05) and IMT of inactive acromegalics was not different from their matched controls (0.61 ± 0.12 mm). FMD was significantly lower in active acromegalics than in matched controls and inactive acromegalics (2.910 ± 2.00 mm, 6.5 ± 2.81 mm, 5.68 ± 2.9 mm respectively; p < 0.005, p < 0.05). FMD of inactive acromegalics was not significantly different from their matched controls (7.96 ± 3.12 mm). A significant inverse relationship was found between GH and FMD in active acromegalics (r = ?0.659, p = 0.010). Conclusion: In active acromegalics, early atherosclerotic changes are not only attributed to the high prevalence of risk factors, but also to the abnormal GH secretion itself.     

Associations of Carotid Artery Intima‐Media Thickness (IMT) With Risk Factors and Prevalent Cardiovascular Disease

Objective. The goal of this study was to compare internal carotid artery (ICA) intima‐media thickness (IMT) with common carotid artery (CCA) IMT as global markers of cardiovascular disease (CVD). Methods. Cross‐sectional measurements of the mean CCA IMT and maximum ICA IMT were made on ultrasound images acquired from the Framingham Offspring cohort (n = 3316; mean age, 58 years; 52.7% women). Linear regression models were used to study the associations of the Framingham risk factors with CCA and ICA IMT. Multivariate logistic regression models and receiver operating characteristic (ROC) curve analysis were used to compare the associations of prevalent CVD with CCA and ICA IMT and determine sensitivity and specificity. Results. The association between age and the mean CCA IMT corresponded to an increase of 0.007 mm/y; the increase was 0.037 mm/y for the ICA IMT. Framingham risk factors accounted for 28.6% and 27.5% of the variability in the CCA and ICA IMT, respectively. Age and gender contributed 23.5% to the variability of the CCA IMT and 22.5% to that of the ICA IMT, with the next most important factor being systolic blood pressure (1.9%) for the CCA IMT and smoking (1.6%) for the ICA IMT. The CCA IMT and ICA IMT were statistically significant predictors of prevalent CVD, with the ICA IMT having a larger area under the ROC curve (0.756 versus 0.695). Conclusions. Associations of risk factors with CCA and ICA IMT are slightly different, and both are independently associated with prevalent CVD. Their value for predicting incident cardiovascular events needs to be compared in outcome studies.     

吸烟者血管内皮舒张功能与颈、股动脉内-中膜厚度相关性的超声研究

目的探讨吸烟者肱动脉流量介导的舒张功能(FMD)与颈、股动脉内-中膜厚度(IMT)的相关性。方法利用高频超声检测34例健康吸烟者及34例健康不吸烟者肱动脉流量介导的舒张功能及颈、股动脉内-中膜厚度。结果健康吸烟者肱动脉FMD明显低于对照组,并且健康吸烟者颈、股动脉IMT明显高于对照组,与颈、肱动脉FMD呈负相关。结论吸烟可导致动脉内皮功能障碍,高频超声能够早期发现吸烟者动脉内皮功能障碍,健康吸烟者无心血管疾病症状时已有颈、股动脉内-中膜厚度的改变。     

Intima-Media Thickness Measurements in the Fetus and Mother During Pregnancy: A Feasibility Study

Fetal intima-media thickness (IMT) has been suggested as a marker of pre-clinical atherosclerosis, and maternal IMT could be altered through dynamic circumstances related to pregnancy. We investigated the feasibility of measurement of IMT at four pre-defined fetal and four pre-defined maternal arterial locations to determine vascular changes that could be associated with impaired vascular function. IMT was measured from the first to third trimester (12–34 wk), in 38 low-risk pregnancies. We imaged a 10-mm region of interest using a Mindray (Shenzhen, China) high-resolution ultrasound machine with automated IMT measurement software. Fetal abdominal aorta IMT was measurable during the second trimester in 71% and during the third trimester in 100% of the case, and umbilical artery IMT was measurable in 50% and 82% of cases during the second and third trimesters, respectively. Fetal IMT measurements were not possible during the first trimester. It was not often feasible to measure the IMT of the fetal common carotid artery, fetal renal artery and maternal iliac artery (maximal 20% of cases). Maternal common carotid artery, abdominal aorta and uterine artery IMTs were measurable throughout pregnancy. There was a significant relation between gestational age and IMT in the umbilical artery (p = 0.03) and a significant relation between body mass index and IMT in the maternal common carotid artery (p = 0.01). IMT measurements are feasible in some maternal and fetal vessels of interest. Further studies are underway to obtain more insight into vascular development during normal and pathologic pregnancies.     

温胆片改善高血压病血管内皮功能障碍的超声研究

目的 探讨温胆片对痰浊型原发性高血压病患者血管内皮功能障碍的调节作用.方法 选择低危、中危组痰浊型原发性高血压患者43例,按随机数字表法分为治疗组23例,对照组20例.在氨氯地平有效控制血压基础上治疗组口服温胆片,对照组口服安慰剂.应用彩超检测治疗前和治疗6个月后患者颈动脉内膜-中膜厚度(IMT),肱动脉充血性和含服硝酸甘油后肱动脉内径的变化.结果 治疗后内皮依赖性舒张功能改善治疗组优于对照组(P<0.05),但硝酸甘油诱发的非内皮依赖性舒张功能2组相比无显著性差异(P>0.05).痰浊型原发性高血压病患者肱动脉内皮依赖性舒张功能与颈动脉IMT呈负相关(r＝-0.596,P<0.05).结论 痰浊型高血压病颈动脉IMT与肱动脉内皮依赖性舒张功能呈负相关,温胆片对肱动脉内皮依赖性舒张功能异常有较好的改善作用.     

Measurement of the Intimal Thickness of the Carotid Artery: Comparison Between 40 MHz Ultrasound and Histology in Rats

Common carotid artery intimal thickness (IT) has been shown to be as useful as a measurement of the whole layer of intima-media thickness (IMT) for evaluating the early phase of atherosclerosis. The aim of this study was to elucidate the relationship between high echogenic intimal thickening (HEIT), which was measured using a 40 MHz ultrasound biomicroscope (UBM), and the histologically determined IT in rat carotid arteries. HEIT was estimated in 10 Wistar-Kyoto rats (group I), 15 spontaneous hypertensive rats (SHR) fed a standard diet (group II) and 10 SHR fed a high-fat diet (group III). IT and IMT measurements were determined in Masson trichrome-stained tissues and were compared with the HEIT and IMT evaluated using the UBM. In group I, the HEIT and the IT were 33 ± 4 μm and 12 ± 1 μm, respectively. In group II, the HEIT and the IT were 68 ± 8 μm and 16 ± 2 μm, respectively. In group III, the HEIT and the IT were 65 ± 26 μm and 33 ± 14 μm, respectively. In SHR, the HEIT and the mean IMT measured with echography were significantly correlated with the IT and the IMT that were determined by histologic measurement (r = 0.60, p = 0.003 and r = 0.53, p = 0.01, respectively). Moreover, HEIT may be associated with the intimal pathology and atherosclerotic burden. The HEIT measurement is a noninvasive method that may be used to assess atherosclerosis in humans. (E-mail:younhj@catholic.ac.kr)     

The effect of statin therapy on endothelial function in type 2 diabetes without manifest cardiovascular disease

OBJECTIVE: Cardiovascular disease (CVD) is the most important cause of mortality in patients with type 2 diabetes and is preceded by endothelial dysfunction. Flow-mediated dilation (FMD) is a noninvasive technique for measuring endothelial dysfunction. We aimed to determine the effect of long-term statin therapy versus placebo on FMD in patients with type 2 diabetes without manifest CVD. RESEARCH DESIGN AND METHODS: A randomized, placebo-controlled, double-blind trial was performed with 250 type 2 diabetic patients. Patients were given 0.4 mg cerivastatin or placebo daily. In August 2001, when cerivastatin was withdrawn from the market, the 0.4 mg cerivastatin was replaced by 20 mg simvastatin, without deblinding the study. The primary end point was the change in FMD, measured by B-mode ultrasound, after 2 years. RESULTS: Determinants of baseline FMD were diabetes duration, common carotid intima-media thickness, and brachial artery diameter. FMD at baseline was 1.51% in the placebo group and 1.66% in the statin group and did not change significantly after 2 years. CONCLUSIONS: The 2-year statin therapy had no effect on FMD in type 2 diabetes. Statin-induced improvement of cardiovascular risk in patients with type 2 diabetes may be mediated through mechanisms other than increased nitric oxide availability.     

超声评价稳定型心绞痛患者颈总动脉结构及功能与肱动脉血管内皮功能的关系

目的探讨稳定型心绞痛患者肱动脉内皮功能与颈总动脉血流动力学、结构的改变及其相互关系。方法30例稳定型心绞痛患者和20例健康者对照组,超声检测并计算血流介导的肱动脉血管舒张功能（FMD）和硝酸甘油介导的肱动脉血管舒张功能（NMD）,颈总动脉内中膜复合体厚度（IMT）、弹性指数（Ep）、僵硬指数（p）及最大剪切率。结果与对照组比较,稳定型心绞痛组FMD降低,颈总动脉IMT增厚,Ep指数、β指数增高,最大剪切率降低,差异均有统计学意义（P〈0．01）。稳定型心绞痛FMD与颈总动脉IMT（r=-0．69,P〈0．01）、Ep指数（r=-0．48,P〈0．01）、β指数（r=-0．54,P〈0．01）呈负相关,与最大剪切率（r=0．57,P〈0．01）呈正相关。结论稳定型心绞痛患者颈动脉血流动力学及结构改变与肱动脉血管内皮功能的变化相关。     

Arterial Compression during Overhead Throwing: A Risk for Arterial Injury?

Case studies reporting aneurysm formation in the axillary artery have been described in overhead throwing athletes, possibly due to repetitive arterial compression by the humeral head that has been transiently observed during sonographic diagnostic arm manoeuvres. Whether compression negatively alters arterial health has not been investigated and was the focus of this study. The throwing arm of elite overhead athletes was screened for inducible axillary artery compression. Compressors (COMP, n = 11, mean age: 20 (SD: 2) year, 7 male, 4 female) were age and sex matched with noncompressing (NONCOMP) athlete controls. Four indices of arterial health (flow mediated dilation [FMD], conduit artery vasodilatory capacity [CADC], glyceryl-trinitrate [GTN]-induced vasodilation and intima-media thickness [IMT]) were assessed with high-resolution ultrasound at the brachial and the axillary, artery. No significant between-group differences were observed at the brachial, or axillary, artery for FMD (brachial: COMP: mean (SD) 6.2 (3.1)%, NONCOMP: 6.1 (3.5)%, p = 0.967, axillary: COMP: 8.0 (5.5)%, NONCOMP: 9.0 (3.6)%, p = 0.602), CADC (brachial: COMP: 10.4 (3.4)%, NONCOMP: 10.4 (5.4)%, p = 0.999, axillary: COMP: 9.6 (4.2)%, NONCOMP: 8.5 (3.2)%, p = 0.492), GTN-induced vasodilation (brachial: COMP: 17.9 (5.1)%, NONCOMP:14.1 (7.2)%, p = 0.173, axillary: COMP: 9.5 (4.3)%, NONCOMP: 7.7 (3.1)%, p = 0.302) or IMT (brachial: p = 0.084, axillary: p = 0.581). These results suggest that transient arterial compression, observed during diagnostic arm manoeuvres in overhead throwing athletes, is not associated with abnormal indices of artery function or structure and that other mechanisms must be responsible for the published cases of aneurysm formation in elite athletes performing overhead throwing actions. (E-mail: c.stapleton@ljmu.ac.uk)     

Autophagy-related 16-like 1gene polymorphism,risk factors for cardiovascular disease and associated carotid intima-media thickness in postmenopausal women

BackgroundEarly identification of asymptomatic postmenopausal women (PW), who are more predisposed to developing cardiovascular disease (CVD), is an important preventive strategy. Autophagy-related 16-like 1 (ATG16L1) is an autophagy gene known to control host immune responses and is associated with a variety of diseases, including CVD.ObjectiveThe aim of the study was to associate the ATG16L1 polymorphism variant with subclinical carotid atherosclerosis in asymptomatic PW.Study designThis cross-sectional study included 210 Brazilian postmenopausal women (age ≥ 45 years with amenorrhea ≥12 months). Clinical, anthropometric and biochemical assessments were performed to evaluate the cardiovascular risk factors. DNA was extracted from buccal cells and the ATG16L1 (T300A) polymorphism was determined by the polymerase chain reaction (PCR). The carotid intima-media thickness and/or the presence of plaques were evaluated by carotid duplex ultrasound. For statistical analysis, the t-test, logistic regression and analysis of covariance (ANCOVA) were used.ResultsThe presence of the polymorphic allele forATG16L1 (T300A) was found in 77.47% (A/G = 49.87%, G/G = 27.60%). The ATG16L1 (T300A) polymorphism is significantly associated with increased carotid intima-media thickness (IMT) after adjustments of the confounding variables (P < .037). No significant associations were observed between the polymorphism with other risk factors for CVD in PW.ConclusionIn postmenopausal women, the ATG16L1 (T300A) polymorphism is significantly associated with increased carotid IMT (marker of atherosclerotic disease) after adjustments of the confounding variables (P < .037). Thus, identifying the ATG16L1 polymorphism is an important strategy for screening asymptomatic PW who are more predisposed to developing CVD.     

年轻人颈动脉内中膜厚度与血压及QT离散度的相关性研究

目的 探讨18～35岁年轻人颈动脉内中膜厚度(intima-media thickness,IMT)与血压及QT离散度的关系.方法 对107例18～35岁年轻人测量血压、体质量指数(body mass index,BMI),根据BMI将研究对象分为正常体质量组、肥胖组,应用超声对两组年轻人颈动脉进行检测,分析两组间颈动脉IMT与血压及QT离散度的关系.结果 与正常体质量组比较,肥胖组血压、IMT、QT离散度增大,差异有统计学意义(P<0.05);IMT与收缩压呈直线正相关[左侧颈动脉IMT(LIMT):r=0.224,P=0.021;右侧颈动脉IMT(RIMT):r=0.193,P=0.047),与舒张压无明显相关(LIMT:r=0.123,P=0.210;RIMT:r=0.138,P=0.159);QT离散度>50 ms者发生IMT异常的危险度高于QT离散度≤50ms者(OR=6.223,P<0.05).结论 18～35岁年轻人IMT与收缩压呈正相关,QT离散度增大是IMT异常的高危因素,QT离散度>50 ms、收缩压>120 mm Hg(1 mm Hg=0.133 kPa)应行IMT检查.     

颈动脉内-中膜厚度与冠心病的相关性

目的探讨颈动脉内中膜厚度(IMT)及斑块与冠状动脉造影(CAG)的相关性.方法研究对象经CAG分为冠心病组和非冠心病组,超声观察颈动脉IMT及有无斑块形成,与CAG结果对照.结果非冠心病组、冠心病不同分支病变组患者颈动脉IMT及斑块指数和冠状动脉疾病记分随CAG严重程度的增加显著增加(P<0.05～0.01),颈动脉IMT冠状动脉疾病记分呈正相关(r=0.726,P＜0.01).与颈动脉IMT及斑块指数对冠心病诊断有较高的敏感性、特异性、粗一致性和Kappa值.结论颈动脉超声是冠心病诊断的一项重要的辅助检查手段.