Gene-environment interaction and its impact on coronary heart disease risk

Coronary heart disease (CHD) is a major cause of mortality in the western world, and is known to be modified by both genetic and environmental factors. This suggests that at the molecular level there is interaction between the gene product(s) and/or the by-products of the environmental insult, and from a statistical viewpoint this implies a deviation from the expected multiplicative effect on risk. In other words genetic risk is modifiable in an environment-specific manner. This Review focuses on recently reported effects of smoking and alcohol (environmental factors) on the impact of variation in the genes for apoE (APOE) and alcohol dehydrogenase (ADHC1) on heart disease risk. Considering gene–environment interaction has the potential not only for improving our understanding of the pathophysiology of the disease, but also in the development and targeting of specific therapies.     

Cardiac disability. The impact of coronary heart disease on patients' daily activities

We studied 100 men with clinically stable coronary heart disease. Their capacity for exertion as defined by treadmill test was compared with the physical and social avocational activities they carried out in their daily routine, as reported by them. Exercise capacity (treadmill time) was strongly correlated with a physician's independent assessment of symptomatic status (anginal history). Although participation in some relatively strenuous elective activities was related slightly to exercise capacity, participation in many household duties and social undertakings bore no relationship to exercise capacity or to other measures of the severity of the underlying heart disease. The patients' own perceptions of their cardiac limitation varied for different activities and for some activities it was determined as much by their own concern and outside advice as by cardiac symptoms. Decreased capacity for exertion seems to exert surprisingly little influence on a cardiac patient's daily routine and interventions aimed at altering one of these measures of performance will not necessarily affect the other.     

冠心病新的危险因素

冠心病是目前全球范围最常见的心血管疾病 ,它的发生是由外界环境因素和内在的多基因调控异常共同作用的结果。已报道的冠心病危险因素有 2 0 0多种 ,包括我们已经熟悉的危险因素和一些新的危险因素。本文就冠心病的一些新的危险因素做一简述     

Cholesterol and coronary heart disease. The importance of patient-specific attributable risk

The value of treating hypercholesterolemia remains controversial despite extensive investigation, in part because of the research orientation of much of the relevant literature. Most published studies report relative measures of risks such as the risk ratio. However, clinicians are concerned with the magnitude of risk, or attributable risk, the difference in risk in those with highest and lowest serum cholesterol levels. Since maximum risk modification is rarely achieved, the attributable risk often overstates the potential benefit of risk factor reduction. A variant of the attributable risk, the practical attributable risk, gives a more realistic estimate of potential benefit. Since clinicians treat individuals and not populations, these measures of risk are most useful if reported for subgroups of patients (eg, men and women, as well as those of varying age). To illustrate these concepts, we review the literature on hypercholesterolemia, report the risk ratio, attributable risk, and practical attributable risk for important patient populations, and discuss the implications for clinical practice.     

The effect of fruit and vegetable intake on risk for coronary heart disease.

BACKGROUND: Many constituents of fruits and vegetables may reduce the risk for coronary heart disease, but data on the relationship between fruit and vegetable consumption and risk for coronary heart disease are sparse. OBJECTIVE: To evaluate the association of fruit and vegetable consumption with risk for coronary heart disease. DESIGN: Prospective cohort study. SETTING: The Nurses' Health Study and the Health Professionals' Follow-Up Study. PARTICIPANTS: 84 251 women 34 to 59 years of age who were followed for 14 years and 42 148 men 40 to 75 years who were followed for 8 years. All were free of diagnosed cardiovascular disease, cancer, and diabetes at baseline. MEASUREMENTS: The main outcome measure was incidence of nonfatal myocardial infarction or fatal coronary heart disease (1127 cases in women and 1063 cases in men). Diet was assessed by using food-frequency questionnaires. RESULTS: After adjustment for standard cardiovascular risk factors, persons in the highest quintile of fruit and vegetable intake had a relative risk for coronary heart disease of 0.80 (95% CI, 0.69 to 0.93) compared with those in the lowest quintile of intake. Each 1-serving/d increase in intake of fruits or vegetables was associated with a 4% lower risk for coronary heart disease (relative risk, 0.96 [CI, 0.94 to 0.99]; P = 0.01, test for trend). Green leafy vegetables (relative risk with 1-serving/d increase, 0.77 [CI, 0.64 to 0.93]), and vitamin C-rich fruits and vegetables (relative risk with 1-serving/d increase, 0.94 [CI, 0.88 to 0.99]) contributed most to the apparent protective effect of total fruit and vegetable intake. CONCLUSIONS: Consumption of fruits and vegetables, particularly green leafy vegetables and vitamin C-rich fruits and vegetables, appears to have a protective effect against coronary heart disease.     

Effect of negative emotions on frequency of coronary heart disease (The Normative Aging Study)

Negative emotions, such as depression and anxiety, have been associated with the development of coronary heart disease (CHD). In multivariate models, negative emotions have predicted CHD outcomes, such as nonfatal myocardial infarction and CHD mortality. Few studies, however, have investigated this relation while controlling for variables associated with the metabolic syndrome or those indicative of sympathetic nervous system activity. We prospectively examined the relation between negative emotions and incident CHD in older men (mean 60.3 ± 7.9 years) participating in the Normative Aging Study (NAS). Four hundred ninety-eight men who completed the Minnesota Multiphasic Personality Inventory (MMPI) and who participated in a subsequent laboratory assessment were included in the study. All men were not on medication and free of diagnosed CHD and diabetes. Negative emotions were measured by the MMPI Welsh A scale, which is comprised of 39 items measuring symptoms of depression and anxiety. Negative emotion score, sociodemographic characteristics, health behaviors, components of the metabolic syndrome, and stress hormones were used to predict incident CHD over a 3-year follow-up period. During follow-up, 45 CHD events were observed. In unadjusted logistic regression analyses, negative emotions significantly predicted the incidence of CHD (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.01 to 1.10, p = 0.02). After adjusting for potential covariates, negative emotions continued to predict the incidence of CHD (OR 1.06, 95% CI 1.01 to 1.12, p = 0.02) A linear, dose-response relation was observed (chi-square 10.8, degree of freedom 2, p = 0.005): participants who had the highest level of negative emotions experienced the greatest incidence of CHD.     

慢性肾病对冠心病发病和预后的影响

近年,慢性肾病发病率和病死率逐年升高．已成为世界范围内危害人们身体健康的重要疾病。心血管疾病往往伴发慢性肾病．慢性肾病患者多因心血管疾病而死亡,并非进展为肾功能衰竭而死亡。美国国家肾脏基金会(NKF)的报告显示,慢性肾病伴心血管疾病病死率是普通人群的10～30倍。     

The white blood cell count and risk for coronary heart disease.

In conclusion, the WBC count has been demonstrated in several epidemiologic studies to be a strong independent predictor of future coronary heart disease. Although it is not possible at this point in time to be certain that the elevated WBC count is a cause rather than a consequence of ischemic heart disease, recent pathophysiologic studies suggest that the white blood cell, in particular the neutrophil, is instrumental in the pathogenesis of myocardial ischemia. It is conceivable that patients who develop acute myocardial ischemia have abnormal leukocyte function before the onset of the acute event, which provides a pathophysiologic milieu for the progression of the atherosclerotic process. Future research must focus on further elucidation of the properties of WBCs and clarification of the role of the activated neutrophil in the process of vascular injury. Quantitative and qualitative changes in leukocyte function may have important implications in the development of CHD.     

The impact of Helicobacter pylori infection on coronary heart disease in a Korean population.

BACKGROUND/AIMS: Although several studies have claimed that Helicobacter pylori (H. pylori) infection is related to cardiovascular disease, it is still uncertain whether it is related to the acute process or the chronic inflammatory atherosclerotic changes. The aim of our study was to confirm the impact of active H. pylori infection on coronary heart disease, acute inflammatory factors, and the coagulation factors. METHODS: A total of 94 patients completed questionnaires about occupation, smoking, past medical history, and socio-economic status. The serum of the subjects was drawn for a low density lipoprotein test, white blood cell count, C reactive protein, fibrinogen, homocysteine, prothrombin time, activated partial thrombin time, plasminogen activator inhibitor type-1, and tissue-type plasminogen test. All of the subjects underwent a coronary angiography and an upper gastrointestinal endoscopy for the diagnosis of coronary heart disease and H. pylori infection, respectively. RESULTS: There was no significant difference in acute inflammatory factors, coagulation factors, atheromatous burden score, and Jeopardy score between the H. pylori-infected group and non-infected group. Odds ratio of H. pylori infection on coronary heart disease was 2.59 (95% CI, 0.80-6.17), but it diminished below 1.0 (95% CI, 0.14-1.36) after adjusting for conventional risk factors such as age, gender, diabetes, hypertension, smoking, body mass index and socio-economic status. CONCLUSIONS: H. pylori infection is not an independent risk factor for coronary heart disease, and it does not alter the coagulation system or evoke the systemic inflammatory response.     

血清淀粉样蛋白A与冠心病及冠心病危险因素的关系

目的 :探讨血清淀粉样蛋白A (SAA)与冠心病 (CHD)及CHD相关危险因素的关系。方法 :用微粒增强免疫比浊法测定SAA的血浆浓度。结果 :急性冠状动脉综合征 (ACS)亚组和稳定型心绞痛 (SAP)亚组SAA血浆浓度均高于对照组 (P <0 .0 1) ;ACS亚组SAA血浆浓度高于SAP亚组 (P <0 .0 1) ;比较CHD危险因素导致CHD发生的危害性 ,SAA >CHD家族史 >TC >吸烟指数 >高血压史。结论 :CHD患者SAA血浆浓度升高可促进动脉粥样斑块的不稳定性 ,导致ACS的发生     

Hypertriglyceridemia and risk of coronary heart disease

Mounting evidence indicates that elevated triglyceride level is a risk factor for coronary heart disease (CHD). The role of triglyceride as a causative agent for CHD is less clear. Hyper-triglyceridemia is frequently associated with a set of complex metabolic abnormalities, including low high-density lipoprotein cholesterol, small dense low-density lipoprotein, central obesity, insulin resistance, and type 2 diabetes. Understanding the physiologic processes that lead to the metabolic disturbances associated with hypertriglyceridemia is essential in investigating the effect of triglyceride on CHD risk.