Coronary heart disease in diabetes mellitus: risk factors and epidemiology.

Cardiovascular complications in diabetic patients, especially type 2, can be classified as microvascular (renal, ophthalmologic and neurologic) and macrovascular (coronary, cerebrovascular and peripheral vascular). Type 1 and 2 diabetic patients have increased cardiovascular risk, especially for coronary artery disease. This has been well established through high-quality studies, as have interventions to ameliorate the major risk factors. The main risk factors for increased incidence of coronary artery disease in diabetic patients include hyperlipidemia, hypertension, smoking, microalbuminuria and hyperglycemia. The therapeutic approach to the type 2 diabetic patient should include--if there is no individual contraindication--diet control, physical exercise, smoking cessation and, particularly, pharmacologic interventions with antiplatelets (mainly aspirin and clopidogrel) and/or anticoagulants (warfarin), angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists, beta-blockers and anti-dyslipidemics (mainly statins), as well as oral antidiabetics (or insulin). In this paper we present and discuss the results of lowering cardiovascular risk in these patients, which should lead to a marked decrease in the incidence of coronary artery, cerebrovascular and peripheral vascular disease, with consequent improvement in prognosis.     

Coronary heart disease risk assessment in diabetes mellitus: comparison of UKPDS risk engine with Framingham risk assessment function and its clinical implications.

AIMS: To assess differences between absolute coronary heart disease (CHD) risks calculated by Joint British Societies (JBS) risk calculator and UKPDS risk engine and its impact on CHD primary prevention management in diabetes mellitus (DM). METHODS: Seven hundred Type 2 DM patients without arterial complications were identified from nine general practices in the Scarborough area. Their absolute 10-year CHD risks were calculated. The differences in the proportion of patients identified for aspirin and statin under JBS and National Institute for Clinical Excellence (NICE) guidelines by these two methods were determined. The proportion of additional patients identified for statin in the Scarborough population as a consequence of CHD risk threshold reduction from 30 to 15% (as recommended by NICE) was also determined. RESULTS: UKPDS risk engine calculated significantly higher mean 10-year CHD risk (UKPDS vs. JBS, 21.5 vs. 18.3%, P < 0.0001). Both methods identified approximately 65% of patients to be eligible for aspirin and statin if NICE recommendations were followed. At a risk threshold of 30%, the UKPDS risk engine identified more patients for statin. Reducing the CHD risk threshold from 30 to 15% for statin initiation will identify an additional 0.5% of the total population for this treatment. CONCLUSIONS: Both methods are comparable in identifying at-risk patients under NICE recommendations. A high proportion has risk levels that merits primary CHD prevention. Lowering the risk threshold for statin treatment has a small numerical impact on the whole population.     

螺内酯对冠心病患者内皮细胞功能的影响

目的　本实验旨在探讨螺内酯对冠心病患者内皮细胞功能的影响。方法　选择 5 0例冠心病患者作为实验组 ,5 0例健康者作为对照组 ,给药前先测定实验组和对照组的内皮素 (ET)、血栓素 A2 (TXA2 )、一氧化氮 (NO)、前列环素 (PGI2 ) ,再予以实验组螺内酯 2 0 m g/ d,3个月后再测定实验组的 ET、TXA2 、NO、PGI2 并进行比较。结果　给药前实验组的 ET、TXA2 水平较对照组高 ,NO、PGI2 水平较对照组低 ;给药后 NO、PGI2 水平较给药前高 ,ET、TXA2 较给药前低。结论　螺内酯可以有效地改善血管内皮细胞功能 ,对逆转冠心病患者内皮细胞功能紊乱起着重要的作用。     

Coronary heart disease risk assessment in diabetes mellitus--a comparison of PROCAM and Framingham risk assessment functions.

AIMS: To assess any differences between coronary heart disease (CHD) risks calculated by the Framingham equation and those calculated by the PROCAM equation in men with and without diabetes mellitus, and whether any such differences are associated with the hypertriglyceridaemia of diabetes mellitus. METHODS: Clinical and biochemical data collected from 1774 men seen in either general practice, a hospital diabetes or lipid clinic. CHD risks were calculated by both the Framingham and PROCAM functions and comparisons made between those patients with and those without diabetes. RESULTS: Of the 1774 men only 996 fulfilled the criteria for assessment by the PROCAM equation and thus further analysis. Patients with diabetes mellitus had significantly higher serum triglyceride levels than those without (1.9 mmol/l vs. 1.7 mmol/l). Median annual CHD risks calculated by the Framingham function were 1.7% in the patients with and 1.32% in the patients without diabetes mellitus, whereas those calculated by the PROCAM function were 0.77% and 0.6%, respectively. Bland-Altman difference plots showed that in both groups of patients the PROCAM equation systematically underestimated risk in comparison with the Framingham equation at low levels of risk but overestimated at higher levels of risk. The shape of the plots in each group of patients was, however, similar. CONCLUSION: There were no systematic differences between CHD risks calculated by the two different equations in patients with diabetes compared with those without, despite the higher serum triglyceride levels associated with diabetes. Restrictions in the use of the PROCAM function meant that only 56% of the original cohort could be assessed in this way. Thus the Framingham equation remains the most suitable method of CHD risk prediction for UK patients with and without diabetes mellitus.     

Circulating endothelial progenitor cells correlate with erectile function in patients with coronary heart disease.

AIMS: The aim of the study was to determine the influence of endothelial progenitor cells (EPC) on erectile dysfunction (ED). EPC play a major role in repair mechanisms of the endothelial monolayer, but the role of EPC in ED is unclear. METHODS AND RESULTS: Circulating levels of CD34(+)/KDR(+) and CD133(+) EPC were determined in 119 patients with known coronary artery disease. ED was evaluated with an ED-score generated from the KEED questionnaire. Prevalence of ED was 59.7%. In univariate analysis, age, hypertension, reduced left ventricular ejection fraction (LVEF), diabetes, and circulating levels of CD133(+) EPC, but not cardiovascular drug treatment were associated with ED. Body mass index (BMI) was positively (r = 0.319, P=0.003) and high-density lipoprotein was negatively (r=-0.246, P=0.034) correlated with ED. Adjustment for age, diabetes, hypertension, BMI, smoking, LVEF, use of statins and lower urinary tract symptoms, and prior coronary intervention revealed low levels of circulating immature CD133(+) EPC as independent risk factor for ED (95% CI -11.183 to -1.7371, P=0.008). CONCLUSION: Reduced levels of circulating CD133(+) EPC are an independent risk factor for ED. Thus, EPC may be a link between cardiovascular risk factors, endothelial dysfunction, and ED.     

冠心病患者循环内皮祖细胞变化及功能的研究

目的探讨冠心病患者外周血循环内皮祖细胞(EPC)变化及其纤溶、黏附和炎症因子表达。方法选择冠心病患者57例(冠心病组)和对照组30例,提取EPC进行数量和细胞集落的比较。用酶联免疫吸附法和底物发光法检测EPC分泌组织型纤溶酶原激活物(tPA)和纤溶酶原激活物抑制剂(PAI)的浓度和活性。用反转录-聚合酶链反应(RT-PCR)检测EPC的tPA、PAI、血管细胞黏附分子1(VCAM-1)、细胞间黏附分子1(ICAM-1)、过氧化物酶体增殖因子活化受体γ(PPARγ)的mRNA表达水平。结果冠心病组EPC数量较对照组明显减少(P0.05),形成细胞集落数、细胞增殖能力也明显降低(P0.05)。与对照组比较,冠心病组EPC分泌的tPA含量和活性明显下降(P0.05),PAI含量和活性明显升高(P0.01)。RT-PCR检测结果显示,与对照组比较,冠心病组EPC的tPA、PPARγmRNA表达减弱,PAI、VCAM-1、ICAM-1 mRNA表达增强(P0.05)。结论冠心病患者外周血循环EPC数量减少,纤溶功能减低,黏附和炎症因子表达增强,其在冠心病发生发展中起到重要作用。     

Coronary heart disease in diabetes mellitus: three new risk factors and a unifying hypothesis

Abstract. The standard risk factors - dyslipidaemia, hypertension and smoking - provide little help in explaining the raised cardiovascular risk in diabetes. It can be calculated that intervening for disturbances of these risk factors could do little to rectify the loss of life expectancy of around 10 years for a middle-aged diabetic man. Three new risk factors are discussed, which together may contribute to some of the excess cardiovascular risk in diabetes. Plasminogen activator inhibitor is an inhibitor of fibrinolysis which is elevated in concentration in diabetic subjects, and may increase both the incidence of thrombotic events and the risk of reinfarction after the initial infarct. Recent work also suggests that high activity of this substance may impair pharmacological fibrinolysis. Proinsulin-like molecules are elevated in concentration in diabetic patients and correlate with levels of a number of other risk factors. Whilst these correlations may represent cause and effect for plasminogen activator inhibitor, there is no evidence that changes in levels of proinsulin-like molecules influence levels of other risk factors. Microalbuminuria provides a powerful indicator of cardiovascular risk in both diabetic and non-diabetic subjects, but whilst the mechanisms for this association are unclear, they are again unlikely to be mediated through changes in levels of standard risk factors. Recent observations of an association between short stature and microalbuminuria suggest that intrauterine or early infant nutrition may represent a common antecedent, these having also been shown to predict both components of the insulin resistance syndrome and cardiovascular disease in adult life.     

小儿川崎病冠状动脉病变及心功能变化观察

目的：探索川崎病患儿冠状动脉损伤情况及其心功能变化。方法：用二维超声心动图检查72例川崎病患儿冠状动脉病变情况：用Cuben’s法检测患儿左室收缩功能；用经二尖瓣多普勒血流图检测患儿左室舒张功能。结果：72例患儿中，检出26例有冠状动脉病变，其中急性或亚急性期单纯冠状动脉扩张21例。川崎病患儿的左室收缩和舒张功能与正常对照组相比无显著性差异（P〉0．05）。结论：川崎病有较高的冠状动脉损伤发生率，尤其是在急性期；超声心动图是检测川崎病冠状动脉病变的有效手段。     

Coronary heart disease risk factors in the elderly

Hypertension, dyslipidemia, impaired glucose tolerance, and obesity remain the major modifiable risk factors for most of the coronary disease afflicting the elderly. The relative risk associated with these established risk factors diminishes with advancing age, but this is offset by a greater absolute and attributable risk. Diabetes is increasing alarmingly in prevalence and operates more powerfully in women, eliminating their coronary disease resistance (relative to men). Interest in this entity now focuses on the insulin resistance syndrome promoted by abdominal obesity that has become so common in the elderly. The isolated systolic hypertension and large pulse pressure that predominate in the elderly is now recognized as a coronary disease hazard. Dyslipidemia, characterized by a high total to high-density lipoprotein cholesterol ratio, is the most predictive lipid profile for coronary disease in the elderly. High triglycerides, accompanied by low high-density lipoprotein cholesterol usually signifies insulin resistance and more atherogenic, small, dense low-density lipoprotein. Left ventricular hypertrophy is an ominous harbinger of coronary disease. Fibrinogen and the leukocyte count are correlated coronary disease risk factors that may indicate unstable lesions. Novel risk factors, such as hemostatic factors, homocysteine, lipoprotein(a), C-reactive protein, and hyperinsulinemia, are worthy of attention, but the efficacy of correcting them in the elderly has not yet been demonstrated. Nor has the efficacy of hormone replacement therapy in women. All the coronary risk factors tend to cluster, and the hazard posed by each is greatly influenced by the burden of coexisting risk factors. High-risk elderly candidates for coronary disease can be efficiently targeted for treatment by global risk assessment, using only the major established risk factors. The distinction between primary and secondary prevention in the elderly is less clear than in the middle-aged because they often have advanced presymptomatic vascular pathology that imposes a coronary event rate comparable to that of the middle-aged who have already sustained a clinical event. Declines in coronary mortality rates in the United States have included the elderly, justifying optimism about the efficacy of preventive measures. Most of the elderly have sufficient remaining life expectancy to warrant vigorous preventive management. Trials of risk factor modification in the elderly indicate that decades of exposure to modifiable risk factors can be countered by measures implemented late in life.     

Coronary heart disease risk factors in Hansen's disease sufferers.

In the frame of an epidemiologic study of Hansen's disease (HD) sufferers, several risk factors have been investigated which might explain the high prevalence of coronary heart disease (CHD) among HD patients. The data analyzed in the present study are derived from 293 HD patients (157 men and 136 women). The patients, after having completed a WHO adopted questionnaire, were given a complete physical examination, a resting and an exercise electrocardiogram, and biochemical as well as hematological examinations. Coronary HD patients, when compared to noncoronary HD patients, showed statistically significant differences in the following parameters: (1) mean age, (2) mean concentration of the electrophoretic fraction of alpha-lipoproteins, (3) deviation from mean weight, (4) prevalence of hypertension, and (5) prevalence of the borderline lepromatous form of HD. However, the differences found when comparing other parameters, such as blood pressure, smoking, diabetes mellitus, total cholesterol, triglycerides, pre-beta and beta-lipoproteins, uric acid, erythrocyte sedimentation rate, ABO blood groups, etc., did not reach the level of significance. These findings suggest that HD sufferers are a special population subgroup with reference to CHD risk factors, differing in many ways from the general population.     

内皮型一氧化氮合酶对内皮祖细胞生物学功能的影响

一氧化氮(NO)及一氧化氮合酶(NOS)参与调节机体多种生理活动,在心血管系统中的作用亦倍受重视.近年来,内皮型一氧化氮合酶(eNOS)的又一生物学作用已引起人们的关注.本文探讨了eNOS在内皮祖细胞的动员、分化和归巢中的作用,及其促进内皮祖细胞的生物学功能.     

Role of inflammation and oxidative stress in endothelial progenitor cell function and mobilization: therapeutic implications for cardiovascular diseases

Endothelial progenitor cells (EPCs) are mobilized from the bone marrow into the peripheral circulation, home to sites of injury, and incorporate into foci of neovascularization, thereby improving blood flow and tissue recovery. Patients with cardiovascular diseases, including coronary artery disease, heart failure, hypertension, and diabetes, have been shown to exhibit reduced number and functional capacity of EPCs. Considerable evidence indicates that EPCs constitute an important endogenous system to maintain endothelial integrity and vascular homeostasis, while reduced number of EPCs has recently been shown to predict future cardiovascular events. Thus, enhancement of EPCs could be of potential benefit for individuals with cardiovascular diseases. The interplay between inflammation and oxidative stress is involved in the initiation, progression, and complications of cardiovascular diseases. Emerging evidence from in vitro and clinical studies suggests that inflammatory and oxidative changes influence EPC mobilization. Drugs with anti-inflammatory and antioxidant properties, currently administered to patients with cardiovascular diseases, such as statins, have been demonstrated to exert beneficial effects on EPC biology. A better understanding of the inflammatory and oxidative mechanisms leading to the numerical and functional impairment of EPCs would provide additional insight into the pathogenesis of cardiovascular disease and create novel therapeutic targets.     

Coronary heart disease in type 2 diabetes mellitus in Isfahan, Iran: prevalence and risk factors

OBJECTIVE: To estimate the prevalence and risk factors of CHD in people with type 2 diabetes mellitus. METHODS AND RESULTS: A cross-sectional study of type 2 diabetic patients was conducted from 2001 to 2004. 1566 consecutive diabetic patients (524 men and 1042 women) from the Isfahan Endocrinology and Metabolism Research Centre outpatient clinics, Iran, have been examined. Part of the examination included an assessment of CHD including 12-lead resting electrocardiogram and a positive response to the angina pectoris section on the Rose questionnaire and self-reported medical history. The mean (SD) age of participants was 50.6 (12.3) years with a mean (SD) duration of diabetes of 7.6 (6.9) years. The prevalence of CHD was 28.0% [95% confidence interval (CI) 25.8, 30.2]. The prevalence of CHD increased with age (P < 0.001). It was associated with gender (P < 0.01), age at diagnosis of diabetes, duration of diabetes, systolic blood pressure (P < 0.001), low density lipoprotein cholesterol, body mass index and smoking (P < 0.05). The age- and gender-adjusted prevalence rate of CHD was 45% higher among insulin-treated patients, 49% higher among patients with BMI >30, and it was positively associated with increasing triglyceride levels and duration of diabetes. Using a stepwise binary logistic regression model, age, BMI, smoking, and insulin treatment were significant independent predictors of CHD. Gender, duration of diabetes, cholesterol and triglycerides had no significant independent association with CHD when other covariates were considered. CONCLUSION: These findings indicate that there is a high prevalence of CHD among the Iranian type 2 diabetic patients, which underlines the need for more programmes of health promotion and lifestyle changes.     

Coronary heart disease mortality and coronary risk factors in Argentina

A marked increase in the coronary heart disease (CHD) mortality of working-age (35-64 years) men and women occurred in Argentina in the 1960s and 1970s. CHD is the leading cause of death in men. In 1978, Argentine men had also one of the highest CHD mortality rates (603.9/100,000) in international mortality statistics and Argentine women (155.2/100,000) were also at the top of these statistics. Stroke mortality has also increased in the younger age-group of men and women over the last decade. The high CHD and stroke mortality rates are compatible with a high prevalence of cardiovascular risk factors. Several surveys have demonstrated that mean serum total cholesterol levels are high, the prevalence of smokers is increasing and the proportion of adequately treated hypertensive patients is low. These results suggest that measures should be introduced to change the Argentine way of life to try to initiate a decline in cardiovascular mortality.     

内皮祖细胞的特性及其在动脉粥样硬化性疾病中的作用

血管内皮是循环血和周围组织间的边界,内皮细胞组成血管内皮,且与炎症、肿瘤、血栓形成等过程密切相关。健康个体,内皮更新处于基础低水平,循环中内皮细胞数量少;当血管内皮发生应急性损伤时,血管壁失去抗血栓形成的能力,循环中内皮细胞迅速增加。研究显示,内皮功能不良是动脉粥样硬化斑块形成的关键事件.