A nation-wide study of atherosclerosis in infants, children and young adults in Japan

Unexpected and atypical clinical presentation of myocardial infarction in infants and children: complex pathogenesis of progressive and lethal disease

BACKGROUND

Myocardial infarction is rare in children but frequently occurs unexpectedly with atypical presentation. It can cause a progressive lethal course unless prompt treatment is initiated.

METHODS

Paediatric cases of myocardial infarction diagnosed by the presence of ischaemic myocardial insults and symptomatic ventricular dysfunction were reviewed retrospectively.

RESULTS

Eighteen patients (5 days to 14 years of age; median 3 months) with myocardial infarction were studied. The aetiology was variable, including congenital coronary anomalies: anomalous left coronary artery from pulmonary artery (five patients), pulmonary atresia with intact ventricular septum with right ventricle-dependent coronary circulation (four), anomalous aortic origin of left coronary artery (three), and Williams syndrome with supravalvar aortic stenosis (one). Two acquired coronary anomalies occurred in one patient with undiagnosed Kawasaki disease with complete thrombotic obstruction of the left coronary artery and another with post-transplant cardiac allograft microangiopathy. Three patients developed thromboembolic coronary artery incidents in normal coronary anatomy. Fourteen patients were less than 1 year of age (78%). Electrocardiographic abnormalities were noted in all patients. Four patients required extracorporeal membrane oxygenation support for severe ventricular dysfunction, none of whom survived. Five patients underwent heart transplant. Five patients died during the same hospitalisation, and one patient died after discharge (overall mortality 33%). Transplant-free survival was 39%.

CONCLUSION

Most myocardial infarction occurred in infants who presented with abrupt onset of non-specific clinical manifestations with progressively deteriorating haemodynamic status resulting in poor transplant-free survival rate. Early diagnosis and treatment are essential to prevent catastrophic outcomes.

Contribution of youth sport participation to physical activity levels and cardiovascular disease risk factors in 5-year-old to 14-year-old children: a study protocol for systematic review and meta-analysis

INTRODUCTION

Cardiovascular disease (CVD) accounts for 18 million deaths per year, disproportionately burdens under-represented racial and ethnic groups, and has economic costs greater than any other health condition. Participation in youth sport may be an effective strategy to improve CVD-related risk factors but studies of youth sport participation have shown mixed results for improving health outcomes. Therefore, the objective of this systematic review is to examine how participation in youth sport contributes to physical activity levels and CVD risk factors in children aged 5-14 years old. A secondary objective is to determine if outcomes are different in racial and ethnic groups.

METHODS AND ANALYSIS

The search will encompass studies published in English, Spanish or Portuguese between January 1995 and April 2024, including five databases (PubMed, Medline, Embase, Cochrane Library and SPORTDiscus). Studies will be included if they are experimental or observational studies, conducted in youths of any health background and assess the relationship of sport participation to physical activity levels or CVD risk factors. Studies must report on at least one of the following outcomes: (1) physical activity levels, (2) blood pressure, (3) lipid fractions, (4) body mass index (5) central adiposity, (6) systemic inflammation and (7) glucose levels/insulin resistance. Study quality will be assessed using the Cochrane Risk of Bias version 1 tool. Narrative descriptions and summary tables will be created to describe studies, results and methodological quality and be synthesised by subsets of studies based on study design and outcomes. In the systematic review, we will categorise the included studies into two subgroups (ie, observational studies, experimental studies) and meta-analyse them separately prior to exploring sources of heterogeneity.

ETHICS AND DISSEMINATION

Ethical approval is not required. The results will be disseminated via peer-reviewed publication and presentation at conferences relevant to this field.

PROSPERO REGISTRATION NUMBER

CRD42023427219.

Atherosclerosis originating from childhood: Specific features

Atherosclerosis is extremely widespread. Traditionally, it is considered a disease of older people, who most often experience problems with the heart and blood vessels. While much attention from the scientific community has been paid to studying the association between aging and atherosclerosis, as well as its consequences, there is evidence that atherosclerosis occurs at an early age. Atherosclerosis may form both during intrauterine development and in childhood. Nutrition plays an important role in childhood atherosclerosis, along with previous infectious diseases and excess weight of both the child and the mother. In the present review, we examined the development of atherosclerosis and the prerequisites in childhood.

Atherosclerosis from Newborn to Adult-Epidemiology, Pathological Aspects, and Risk Factors

Cardiovascular disease is the leading cause of mortality and morbidity throughout the world, accounting for 16.7 million deaths each year. The underlying pathological process for the majority of cardiovascular diseases is atherosclerosis, a slowly progressing, multifocal, chronic, immune-inflammatory disease that involves the intima of large and medium-sized arteries. The process of atherosclerosis begins in childhood as fatty streaks-an accumulation of lipids, inflammatory cells, and smooth muscle cells in the arterial wall. Over time, a more complex lesion develops into an atheroma and characteristic fibrous plaques. Atherosclerosis alone is rarely fatal; it is the further changes that render fibrous plaques vulnerable to rupture; plaque rupture represents the most common cause of coronary thrombosis. The prevalence of atherosclerosis is increasing worldwide and more than 50% of people with circulatory disease die of it, mostly in modern societies. Epidemiological studies have revealed several environmental and genetic risk factors that are associated with the early formation of a pathogenic foundation for atherosclerosis, such as dyslipidemia, hypertension, diabetes mellitus, obesity, and smoking. The purpose of this review is to bring together the current information concerning the origin and progression of atherosclerosis in childhood as well as the identification of known risk factors for atherosclerotic cardiovascular disease in children.

A Hidden Organism, Chlamydia in the Age of Atherosclerosis

Atherosclerosis is a chronic inflammatory disease. It is still the leading cause of mortality and morbidity in the world. Inflammation in the vessels plays the most important role in the pathogenesis of atherosclerosis. Many studies have been emphasized that Chlamydia pneumoniae triggers inflammation in the vessels and associated with atherosclerosis. It is stated that most of the chlamydial infections are asymptomatic and around 40% of adult individuals are infected. Chlamydia has different subgroups. It was thought to be a virus due to its intracellular pathogenicity, but it was included in the bacteria genus because it contains DNA and RNA chromosomes and has enzymatic activity. Chlamidya can easily be transmitted through the respiratory tract and sexual transmission. Seroepidemiological and pathological studies of atherosclerotic plaques showed the presence of Chlamydia in the plaque. This section will provide relationship between Chlamydia and atherosclerosis on the recent researces and current information will be discussed.

Practical, Evidence-Based Approaches to Nutritional Modifications to Reduce Atherosclerotic Cardiovascular Disease: An American Society For Preventive Cardiology Clinical Practice Statement

Despite numerous advances in all areas of cardiovascular care, cardiovascular disease (CVD) is the leading cause of death in the United States (US). There is compelling evidence that interventions to improve diet are effective in cardiovascular disease prevention. This clinical practice statement emphasizes the importance of evidence-based dietary patterns in the prevention of atherosclerotic cardiovascular disease (ASCVD), and ASCVD risk factors, including hyperlipidemia, hypertension, diabetes, and obesity. A diet consisting predominantly of fruits, vegetables, legumes, nuts, seeds, plant protein and fatty fish is optimal for the prevention of ASCVD. Consuming more of these foods, while reducing consumption of foods with saturated fat, dietary cholesterol, salt, refined grain, and ultra-processed food intake are the common components of a healthful dietary pattern. Dietary recommendations for special populations including pediatrics, older persons, and nutrition and social determinants of health for ASCVD prevention are discussed.

Atherosclerosis: Known and unknown

Atherosclerotic disease, such as myocardial infarction and stroke, is the number one killer worldwide. Atherosclerosis is considered to be caused by multiple factors, including genetic and environmental factors. In humans, it takes several decades until the clinical complications develop. There are many known risk factors for atherosclerosis, including hypercholesterolemia, hypertension, diabetes and smoking, which are involved in the pathogenesis of atherosclerosis; however, it is generally believed that atherosclerosis is vascular chronic inflammation initiated by interactions of these risk factors and arterial wall cells. In the past 30 years, the molecular mechanisms underlying the pathogenesis of atherosclerosis have been investigated extensively using genetically modified animals, and lipid-reducing drugs, such as statins, have been demonstrated as the most effective for the prevention and treatment of atherosclerosis. However, despite this progress, questions regarding the pathogenesis of atherosclerosis remain and there is a need to develop new animal models and novel therapeutics to treat patients who cannot be effectively treated by statins. In this review, we will focus on two topics of atherosclerosis, "pathology" and "pathogenesis," and discuss unanswered questions.

Early life factors and their relevance to intima-media thickness of the common carotid artery in early adulthood

BACKGROUND

Early life factors may predispose an offspring to cardiovascular disease in later life; relevance of these associations may extend to ‟healthy" people in Western populations. We examined the prospective associations between early life factors and adult carotid intima-media thickness (IMT), a surrogate marker of atherosclerosis, in a healthy German population.

METHODS

We studied term participants (n = 265) of the DONALD Study, with bilateral sonographic measurements of IMT (4-8 measurements on both left and right carotid artery) at age 18-40 years and prospectively collected data on early life factors (maternal and paternal age at child birth, birth weight, gestational weight gain and full breastfeeding (>17weeks). Mean IMT values were averaged from mean values of both sides. Associations between early life factors and adult IMT were analyzed using multivariable linear regression models with adjustment for potential confounders.

RESULTS

Adult mean IMT was 0.56mm, SD 0.03, (range: 0.41 mm-0.78 mm). Maternal age at child birth was of relevance for adult IMT, which was sex specific: Advanced maternal age at child birth was associated with an increased adult IMT among female offspring only (β 0.03, SE 0.009 mm/decade, P = 0.003), this was not affected by adult waist circumference, BMI or blood pressure. Other early life factors were not relevant for IMT levels in males and females.

CONCLUSION

This study suggests that advanced maternal age at child birth is of prospective relevance for adult IMT levels in a healthy German population and this association may be of adverse relevance for females only.

Epigenetic control of atherosclerosis via DNA methylation: A new therapeutic target?

Atherosclerosis is a disease in which lipid-laden plaques are developed inside the vessel walls of arteries. The immune system is activated, resulting in inflammation and oxidative stress. Endothelial cells (ECs) are activated, arterial smooth muscle cells (SMCs) proliferate, macrophages are activated, and foam cells are developed, leading to dysfunctional ECs. Epigenetic regulatory mechanisms, including DNA methylation, histone modifications, and microRNAs are involved in the modulation of genes that play distinct roles in several aspects of cell biology and physiology, hence linking environmental stimuli to gene regulation. Recent research has investigated the involvement of DNA methylation in the etiopathogenesis of atherosclerosis, and several studies have documented the role of this mechanism in various aspects of the disease. Regulation of DNA methylation plays a critical role in the integrity of ECs, SMC proliferation and formation of atherosclerotic lesions. In this review, we seek to clarify the role of DNA methylation in the development of atherosclerosis through different mechanisms.

The early detection of atherosclerosis in type 1 diabetes: why, how and what to do about it

The major cause of morbidity and often premature mortality in people with type I diabetes (T1D) is cardiovascular disease owing to accelerated atherosclerosis. We review publications relating to the rationale behind, and clinical tests for, detecting and treating early atherosclerosis in people with T1D. Currently available tools for atherosclerosis assessment include risk equations using vascular risk factors, arterial intima-media thickness, the ankle-brachial index, coronary artery calcification and angiography, and for more advanced lesions, intravascular ultrasound and optical coherence tomography. Evolving research tools include risk equations incorporating novel clinical, biochemical and molecular tests; vascular MRI and molecular imaging. As yet there is little information available to quantify early atherosclerosis. With better means to control the vascular risk factors, such as hypertension, dyslipidaemia and glycaemic control, and emerging therapies to control novel risk factors, further epidemiologic and clinical trials are merited to facilitate the translation into clinical practice of robust means to detect, monitor and treat early atherosclerosis in those with T1D.

Trends in Serum Lipid Levels of a 10- and 13-Year-Old Population in Fukuroi City, Japan (2007-2017)

Background

Current trends in serum lipid levels among children are likely to be important predictors of future cardiovascular disease prevalence. However, no studies have examined trends in low-density lipoprotein cholesterol (LDL-C) levels in Japanese children.

Methods

We investigated trends in LDL-C levels from 2008 through 2017 and HDL-C levels from 2007 through 2017 in a population of 10- and 13-year-old children in Fukuroi City, Japan. We analyzed 17,838 children, accounting for 93.8% of all fifth and eighth graders in the entire city. Adverse lipid levels were defined as follows: 130 mg/dL or higher for LDL-C, and lower than 40 mg/dL for HDL-C. The Jonckheere-Terpstra and Cochran-Armitage tests were used to evaluate secular trends in mean serum lipid levels and prevalence of dyslipidemia, respectively.

Results

There were no significant trends in BMI during the study period. In children aged 10 years, serum levels of LDL-C and HDL-C showed significant positive associations with calendar year during the study period for both sexes. A significant increase in HDL-C levels was observed in girls aged 13 years. On the other hand, no significant trends were observed in the prevalence of high LDL-C or low HDL-C regardless of sex or age, while the prevalence of high non-HDL-C showed a significant increase in boys.

Conclusions

In the Fukuroi population, serum levels of LDL-C and HDL-C slightly increased in both boys and girls aged 10 years, and HDL-C levels slightly increased in girls aged 13 years, during the past decade.

Importance of cystatin C and uric acid levels in the association of cardiometabolic risk factors in Japanese junior high school students

BACKGROUND

Serum cystatin C (CysC), a novel marker of renal function, is associated with the components of metabolic syndrome in adults. Little is known about the utility of CysC and its association with cardiometabolic risks in young subjects.

METHODS AND RESULTS

In a cohort of 454 Japanese junior high school students, the distribution of serum CysC levels and associated variables were analyzed. CysC levels were significantly higher in boys than in girls (0.92±0.10mg/L vs. 0.77±0.08mg/L, p<0.001). CysC was significantly correlated with serum creatinine (r=0.473, p<0.001), and serum uric acid (SUA) (r=0.546, p<0.001). Multivariable regression analysis revealed significant associations between CysC and SUA in all subjects (β=0.241, p<0.001), and in boys and girls separately (β=0.264 and 0.240, respectively, both p<0.001). Importantly, subjects with elevation of both serum CysC and SUA levels had the highest ratio of triglyceride to high-density lipoprotein cholesterol.

CONCLUSIONS

CysC had significant associations with both creatinine and SUA in Japanese junior high school students. The concomitant elevation of serum CysC and SUA levels was associated with subclinical lipid metabolism dysregulation, and suggested the presence of cardiometabolic risk accumulation.

Infection with Chlamydia pneumoniae as a cause of coronary heart disease: the hypothesis is still untested

Review of the possible role of Chlamydia pneumoniae infection in the pathogenesis of heart disease.

Arizona Study of Aging and Neurodegenerative Disorders and Brain and Body Donation Program

The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.

Do differences in risk factors explain the lower rates of coronary heart disease in Japanese versus U.S. women?

BACKGROUND

Mortality from coronary heart disease (CHD) in women in Japan is one of the lowest in developed countries. In an attempt to shed some light on possible reasons of lower CHD in women in Japan compared with the United States, we extensively reviewed and analyzed existing national data and recent literature.

METHODS

We searched recent epidemiological studies that reported incidence of acute myocardial infarction (AMI) and examined risk factors for CHD in women in Japan. Then, we compared trends in risk factors between women currently aged 50-69 years in Japan and the United States, using national statistics and other available resources.

RESULTS

Recent epidemiological studies have clearly shown that AMI incidence in women in Japan is lower than that reported from other countries, and that lipids, blood pressure (BP), diabetes, smoking, and early menopause are independent risk factors. Comparing trends in risk factors between women in Japan and the United States, current levels of serum total cholesterol are higher in women in Japan and levels have been similar at least since 1990. Levels of BP have been higher in in Japan for the past 3 decades. Prevalence of type 2 diabetes has been similar in Japanese and white women currently aged 60-69 for the past 2 decades. In contrast, rates of cigarette smoking, although low in women in both countries, have been lower in women in Japan.

CONCLUSIONS

Differences in risk factors and their trends are unlikely to explain the difference in CHD rates in women in Japan and the United States. Determining the currently unknown factors responsible for low CHD mortality in women in Japan may lead to new strategy for CHD prevention.

Macrovascular angiopathy in children and adolescents with type 1 diabetes

Diabetes represents one of the most common diseases globally. Worryingly, the worldwide incidence of type 1 diabetes (T1D) is rising by 3% per year. Despite the rapid increase in diabetes incidence, recent advances in diabetes treatment have been successful in decreasing morbidity and mortality from diabetes-related retinopathy, nephropathy, and neuropathy. In contrast, there is clear evidence for the lack of improvement in mortality for cardiovascular diseases (CVDs). This emphasizes the importance of focusing childhood diabetes care strategies for the prevention of CVD in adulthood. Furthermore, although most work on diabetes and macrovascular disease relates to type 2 diabetes, it has been shown that the age-adjusted relative risk of CVD in T1D far exceeds that in type 2 diabetes. As T1D appears predominantly during childhood, those with T1D are at greater risk for coronary events early in life and require lifelong medical attention. Because of the important health effects of CVDs in children and adolescents with T1D, patients, family members, and care providers should understand the interaction of T1D and cardiovascular risk. In addition, optimal cardiac care for the patient with diabetes should focus on aggressive management of traditional cardiovascular risk factors to optimize those well-recognized as well as new specific risk factors which are becoming available. Therefore, a complete characterization of the molecular mechanisms involved in the development and progression of macrovascular angiopathy is needed. Furthermore, as vascular abnormalities begin as early as in childhood, potentially modifiable risk factors should be identified at an early stage of vascular disease development.

Study on the reference values of serum lipids in children aged 3-18 years old in Beijing, China

BACKGROUND

The present study was designed to explore the reference values of serum lipids in children in Beijing.

METHODS

A total of 1071 healthy children from Beijing between 3 and 18 years of age were enrolled and divided into four groups: A, 3-5-year-old group; B, 6-9-year-old group; C, 10-14-year-old group; and D, 15-18-year-old group. Blood samples were obtained from the cubital veins of the participants under a fasting condition. A Hitachi 7600 Automatic Biochemistry Analyzer was used to determine the serum levels. The cut-off points of reference values were the 75th and 95th percentiles for total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) while the 25th and 5th percentiles were used for high-density lipoprotein cholesterol (HDL-C) concentrations.

RESULTS

The highest 95th percentiles of TC among the four groups were 5.34 mmol/L for boys and 5.11 mmol/L for girls. Compared with those of boys, female TG levels were obviously higher in the 10-14-year-old group (P < 0.05) and HDL-C levels were significantly higher in the 15-18-year-old group (P < 0.05). The serum TC, HDL-C, and LDL-C all peaked during the 6-9-year-old period and then declined during the adolescent stage. Also, the serum TG continuously increased with a relative plateau during the 6-14-year-old period. Obese and overweight children had higher TG and LDL-C levels but lower HDL-C levels.

CONCLUSION

This study showed a picture of the serum lipids distribution in Chinese children and found that their TC levels were lower than those of children in Japan, Iran, and France, but were higher than those of Italian children.

Atherosclerotic cardiovascular disease beginning in childhood

Although the clinical manifestations of cardiovascular disease (CVD), such as myocardial infarction, stroke, and peripheral vascular disease, appear from middle age, the process of atherosclerosis can begin early in childhood. The early stage and progression of atherosclerosis in youth are influenced by risk factors that include obesity, hypertension, dyslipidemia, and smoking, and by the presence of specific diseases, such as diabetes mellitus and Kawasaki disease (KD). The existing evidence indicates that primary prevention of atherosclerotic disease should begin in childhood. Identification of children at risk for atherosclerosis may allow early intervention to decrease the atherosclerotic process, thereby preventing or delaying CVD. This review will describe the origin and progression of atherosclerosis in childhood, and the identification and management of known risk factors for atherosclerotic CVD in children and young adults.

A critique of paradoxes in current advice on dietary lipids

Beliefs about credible hypotheses of dietary causes of disease still need well-defined mediators to test for logical proof or disproof. We know that food energy causes transient postprandial oxidative insults that may not be fully reversible. Also, eating vitamin-like 18-carbon polyunsaturated fatty acids (PUFA) in foods maintains the 20- and 22-carbon highly unsaturated fatty acids (HUFA) in tissues. Tissue HUFA form hormone-like mediators that each amplify transient postprandial insults into fatal inflammatory, thrombotic and arrhythmic events in cardiovascular disease, a major preventable cause of death. Similar diet-based amplified events may also occur in other inflammatory proliferative disorders including cancer, dementia, arthritis and asthma. Puzzling paradoxes come from fragmented views of this situation which convey incomplete knowledge in oversimplified messages. Tools now exist to demonstrate successful prevention of two fatal food imbalances with credible dietary preventive interventions, but organizers and financers to help gather the evidence remain unknown. The overall evidence accumulated about diet, disease and death may be nearing a paradigm shift in which prior observed facts remain while beliefs about their accepted interpretation change.

Less subclinical atherosclerosis in Japanese men in Japan than in White men in the United States in the post-World War II birth cohort

Coronary heart disease incidence and mortality remain very low in Japan despite major dietary changes and increases in risk factors that should have resulted in a substantial increase in coronary heart disease rates (Japanese paradox). Primary genetic effects are unlikely, given the substantial increase in coronary heart disease in Japanese migrating to the United States. For men aged 40-49 years, levels of total cholesterol and blood pressure have been similar in Japan and the United States throughout their lifetimes. The authors tested the hypothesis that levels of subclinical atherosclerosis, coronary artery calcification, and intima-media thickness of the carotid artery in men aged 40-49 years are similar in Japan and the United States. They conducted a population-based study of 493 randomly selected men: 250 in Kusatsu City, Shiga, Japan, and 243 White men in Allegheny County, Pennsylvania, in 2002-2005. Compared with the Whites, the Japanese had a less favorable profile regarding many risk factors. The prevalence ratio for the presence of a coronary calcium score of > or =10 for the Japanese compared with the Whites was 0.52 (95% confidence interval: 0.35, 0.76). Mean intima-media thickness was significantly lower in the Japanese (0.616 mm (standard error, 0.005) vs. 0.672 (standard error, 0.005) mm, p < 0.01). Both associations remained significant after adjusting for risk factors. The findings warrant further investigations.

Prevalence of atherosclerosis in relation to atomic bomb radiation exposure: an RERF Adult Health Study

PURPOSE

To determine whether exposure to atomic bomb radiation altered the prevalence of asymptomatic atherosclerosis.

MATERIAL AND METHODS

In a cross-sectional analysis, we examined aortic arch calcification by plain chest radiography and common carotid artery intima-media thickness (IMT) by ultrasonography among 1804 survivors of the atomic bombing in Hiroshima. We evaluated the association between atherosclerotic changes and radiation exposure, while adjusting for potentially confounding factors.

RESULTS

Multivariate logistic regression analysis showed that aortic arch calcification was significantly associated with radiation exposure (p < 0.05). The odds ratio at 1 Gy was 1.30 (95% confidence interval [CI]: 1.05 - 1.53) for men and 1.31 (95% CI: 1.13 - 1.51) for women. Carotid artery IMT did not vary significantly with radiation dose (p = 0.18).

CONCLUSION

Radiation dose contributed to the prevalence of aortic atherosclerosis but not carotid artery atherosclerosis in atomic bomb survivors.

Identification of mildly oxidized low-density lipoprotein (electronegative LDL) and its auto-antibodies IgG in children and adolescents hypercholesterolemic offsprings

BACKGROUND

Oxidative modification of low-density lipoproteins (LDL) is an essential step in atherogenesis, generating minimally oxidized LDL, also called electronegative LDL [LDL(-)], which has chemotactic, cytotoxic and immunogenic properties.

METHODS AND RESULTS

Serum LDL(-) and anti-LDL(-) auto-antibodies (IgG) were evaluated in 28 children and adolescents with familial hypercholesterolemia (FH) antecedents, with or without early coronary artery disease in first-degree relatives (eCAD), hypercholesterolemic (hc) or normocholesterolemic (nc) versus a control group of normocholesterolemic children without pathologic antecedents (C). ELISA method was used for detection of LDL(-) and anti-LDL(-) IgG. LDL(-) serum levels did not differ among the four groups (FH-eCAD-hc 41.4 +/- 24.9 microg/dl; FH-hc 38.3 +/- 11.2 microg/dl; FH-nc 47.3 +/- 17.0 microg/dl and C 44.2 +/- 28.8 microg/dl, p = 0.659). However, IgG anti-LDL(-) auto-antibodies were significantly higher in the control group in comparison to the FH groups with or without eCAD, independent of hypercholesterolemia or normocholesterolemia (FH-eCAD-hc 0.825 +/- 0.289 microg/dl; FH-hc 0.667 +/- 0.307 microg/dl; FH-nc 0.763 +/- 0.204 microg/dl and C 1.105 +/- 0.233 microg/dl, p = 0.006). When the auto-antibodies of groups with FH, with or without eCAD and with or without hypercholesterolemia were compared, no differences were found (p = 0.509).

CONCLUSION

These results showed that FH and/or eCAD children and adolescents have lower titers of auto-antibodies anti-LDL(-) than children from normal families, independent of serum LDL-cholesterol or serum LDL(-).

Differences between coronary disease and stroke in incidence, case fatality, and risk factors, but few differences in risk factors for fatal and non-fatal events

AIMS

To compare incidence and mortality of coronary and stroke events, and risk factors for non-fatal and fatal events, respectively.

METHODS AND RESULTS

Incidence and mortality were compared in all coronary (n=559 341) and stroke (n=530 689) events in Sweden from 1987 to 2001. Data from 28 years of follow-up of a random sample of 7400 men aged 47-55 and free of disease at baseline were used to compare risk factors. Incidence and 28 days of case fatality were considerably higher for coronary disease than for stroke, especially for men. Incidence of coronary disease decreased, especially for men (P=0.0001 for both sexes), and mortality declined for both men and women during 1987-2001 (P=0.0001 for both sexes). Stroke incidence declined slightly (P=0.0001 for both sexes), and there was a decline of mortality (P=0.0001 for both sexes). Out-of-hospital mortality during the first 28 days was higher than in-hospital mortality for coronary events, whereas for stroke, in-hospital mortality was higher (in men) or the same (in women) as out-of-hospital mortality. High serum cholesterol was a strong risk factor for coronary events, but not for stroke. High blood pressure was a stronger risk factor for stroke. About 50% of men with both stroke and coronary disease died from coronary disease.

CONCLUSION

Several differences regarding incidence, mortality, prognosis, and risk factors for stroke and coronary disease point towards different pathologies.

Comparison of coronary and aortic atherosclerosis in youth from Japan and the USA

This paper reports the results of the largest autopsy-based comparative study of atherosclerotic lesions between young Japanese and Americans, aged 15-34 years and autopsied between 1987 and 1995, by analyzing the data from the Japanese second nation-wide study of atherosclerosis and Pathobiological Determinants of Atherosclerosis in Youth study in the USA. In the right coronary arteries, in Japanese, fatty streaks were well established in the second decade of life with very little increase in the remaining age groups up to age of 34 years. In contrast, in American subjects, the average percentage of surface involvement of fatty streaks and raised lesions proceeded steadily with age without an obvious plateau throughout the 20-year period. The extent and prevalence of the raised lesions was much greater in Americans than in Japanese in 25-29 and 30-34-year age groups. Moreover, the rate of progression of raised lesions was much more rapid in Americans. These findings are in keeping with the fact that coronary heart disease (CHD) death rates are much higher in the USA than in Japan. In light of data showing that the risk factor profiles for CHD have become very similar between the two countries, these differences need to be explained.

Trends in levels of cholesterol in Japanese children from 1993 through 2001

BACKGROUND

Cardiovascular risk factors in children raise the possibility of cardiovascular disease later in life. We attempted to determine the current trends in cardiovascular risk factors among Japanese children.

METHODS

We examined fifth-graders at all the elementary schools in Iwata city in Japan every year from 1993 through 2001. We examined 4,673 boys and 4,484 girls, aged 10-11 years. Height, body weight, body mass index, and serum total cholesterol concentrations were measured. Regression analysis was used to evaluate the trends. The independent variable was the calendar year of the examination. The dependent variables were the anthropometric values and the serum total cholesterol concentration in each individual. The relationships between the year and the prevalence of hyperlipidemia and the prevalence of obesity were also examined.

RESULTS

Both the heights of the girls and the body weights of the both sexes were positively associated with the year. The body mass index in both girls and boys also showed positive relationships with the calendar year. In addition, there was an increase in the prevalence of obesity. Concerning the levels of cholesterol, positive regression coefficients were shown between the total cholesterol concentration and the year in both sexes. Furthermore, there was an increase in prevalence of hyperlipidemia.

CONCLUSION

These results indicate that during the past decade among Japanese children involved in the study, both the body mass index and the serum total cholesterol concentrations increased.

The Levels of Serum Low-Density Lipoprotein Cholesterol Using Direct Measurement in Healthy Japanese School Children

This study aimed to investigate the levels of serum low-density lipoprotein cholesterol (LDLC) using direct measurement in healthy Japanese school children. The subjects were 621 children (325 boys and 296 girls) aged 9 to 10 in the 4th grade, and 688 children (334 boys and 354 girls) aged 12 to 13 in the 7th grade. The levels of serum LDLC and high-density lipoprotein cholesterol were measured by direct determination (Cholestest LDL and Cholestest NHDL; Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan). In boys in the 4th grade, the mean, the 75th, the 90th and the 95th percentiles of LDLC levels (mg/dl) were 91.6, 104, 124 and 134, respectively. In girls in the 4th grade, they were 92.8, 108, 122 and 130. In boys in the 7th grade, they were 83.4, 96, 113 and 123. In girls in the 7th grade, they were 93.0, 106, 126 and 137. Serum LDLC levels in boys in the 7th grade were lower than those of other groups. The direct measurement of serum LDLC level is useful for evaluation of dyslipidemia in healthy school children, because the method is applicable to non-fasting serum.

Effects of Lentinus edodes mycelia on dietary-induced atherosclerotic involvement in rabbit aorta

Lentinus edodes mycelia lowers cholesterol levels and acts as an immunomodulator and tumor-inhibitor in animal models. Lentinus edodes mycelia contains eritadenine (C(9)H(11)O(4)N(5)) and glucans among other biological compounds. However, whether or not Lentinus edodes mycelia is anti-atherogenic remains unknown. We examined the effect of Lentinus edodes mycelia (L.E.M) on atherosclerosis in a rabbit model. Thirty-two Japanese white male rabbits were fed with 1.0% cholesterol for 8 weeks, then divided into groups and given 1) 1.0% cholesterol for over 8 weeks (control), 2) 1.0% cholesterol and 1.0% L.E.M for over 8 weeks, 3) 1.0% cholesterol and 2.0% L.E.M for over 8 weeks, and 4) 1.0% cholesterol and 4.0% L.E.M for over 8 weeks (n=8 each group). Total cholesterol (TC) was measured periodically throughout the experiment. After the experimental periods, the aortas were removed and atherosclerotic lesions were examined histologically, immunohistochemically and morphometrically to determine surface involvement (SI) and an atherosclerotic index (AI). Body weight and TC did not significantly differ among the four groups. Decreases in SI were significant in the 1% L.E.M (26.2+/-10.8%) and 2% L.E.M (29.3+/-15.7%) groups compared with the control (48.7+/-15.3%; p < 0.05). The AI was significantly decreased in the 1% L.E.M (6.62+/-4.31) and 2% L.E.M (7.49+/-3.49) groups compared with the control (16.96+/-9.21; p < 0.05). Foam cells aggregated in thickened intima of dietary-induced atherosclerotic lesions in the rabbit aorta. In contrast, the numbers of foam cells in the intima decreased in the experimental group. No-cholesterol-lowering action or dose-dependant effects of L.E.M were determined in this study, but atherosclerotic development was significantly inhibited, indicating that L.E.M had anti-atherogenic properties. L.E.M may inhibit atherosclerotic development in rabbit aorta and be beneficial as a nutritional supplement.

New criteria of normal serum lipid levels in Japanese children: the nationwide study

AIM

To make new criteria of serum lipid levels in current Japanese children using the large nationwide data provided from Japan Association of Health Service for the analysis.

METHODS

The subjects were schoolchildren who received screening and care programs for lifestyle related diseases since 1993-1999. Serum total cholesterol (TC), high-density lipoprotein cholesterol (HDLC) and triglyceride (TG) levels were measured, and low-density lipoprotein cholesterol (LDLC) levels were calculated. Serum lipid levels were analyzed by age and sex. For each serum lipid, we extracted age- and sex-specific group which the mean value was not statistically different from that in 1999 by Student's t-test analysis.

RESULTS

The level below the 75th percentile was defined to be acceptable, from the 75th to 95th to be borderline and over the 95th to be high in TC/LDLC. The level below the fifth percentile in HDLC was defined to be low and the level over the 95th percentile in TG to be high. Therefore, TC level was categorized as follows: acceptable < 190 mg/dL; borderline 190-219 mg/dL; and high > 220 mg/dL. The LDLC level was also categorized into: acceptable < 110 mg/dL; borderline 110-139 mg/dL; and high > 140 mg/dL. The cut-off value in TG was determined to be 140 mg/dL and in HDLC was 40 mg/dL.

CONCLUSIONS

This new criteria should prove valuable in health strategies for rational prevention and intervention in children. It should be emphasized to provide some intervention for Japanese children immediately.

DNA methylation and atherosclerosis

DNA methylation is a major epigenetic modification of the genome that has the potential to silence gene expression. Recently, the role of epigenetic alteration as a distinct and crucial mechanism to regulate genes governing cell proliferation in atherosclerosis has emerged. Aberrant methylation is related to aging, and, because it affects a large number of CpG islands, age-related methylation may be an important contributor to increased atherosclerosis among older individuals by upregulating atherosclerosis-susceptible genes and downregulating atherosclerosis-protective genes. Further dissection of epigenetic alterations in atherosclerosis and aging will lead to the identification of novel epigenetic modifiers and improved diagnosis and treatment for atherosclerosis-related diseases.

Coronary heart disease mortality among men aged 35-44 years by prefecture in Japan in 1995-1999 compared with that among white men aged 35-44 by state in the United States in 1995-1998: vital statistics data in recent birth cohort

The levels of risk factors for coronary heart disease (CHD) in men in the post World War II (WWII) birth cohort are almost similar between Japan and the USA, except for the considerably higher prevalence of cigarette smoking in Japan and the much higher prevalence of obesity in the USA. The present study evaluated the CHD mortality among men in the post WWII birth cohort by prefecture in Japan in 1995-1999 and then compared the data with those for white men in different states in the USA. There was a greater than 2-fold difference in CHD mortality among men aged 35-44 by prefecture in Japan: 5.3/100,000 in Kumamoto vs 12.6/100,000 in Tochigi. CHD mortality among men aged 35-44 in the top 3 prefectures in Japan is about half that of white men in the USA and is similar to that of white men in the lowest 3 states. The much lower CHD mortality in Japan does not appear to be caused by differences in the classification of causes of death and the results suggest that there may be strong and important protective factors that reduce the risk of CHD in Japan.

Second nation-wide study of atherosclerosis in infants, children and young adults in Japan

This paper reports the results of the second nation-wide cooperative study of atherosclerosis in young Japanese, aged from 1 month to 39 years, who were autopsied between 1991 and 1995. Atherosclerotic lesions in 1066 aortas and 974 coronary arteries were classified into fatty streaks, fibrous plaques and complicated lesions and quantificated with the point-counting method. The results of this study were compared with those of the former study, which was conducted 13 years earlier in almost the same fashion as this study. Atherosclerosis of aorta, which was determined by surface involvement (SI) of atherosclerotic lesions and atherosclerotic index (AI), increased with age in both sexes of the former and the present studies and their tendency for the progression of the extent of atherosclerotic lesions appeared to be similar. In the coronary arteries, the mean values of SI and AI in the males of the present study were greater significantly than those in the male of the former studies and in the female of the both studies in the third and fourth decades. This difference suggests that atherosclerotic lesions are increasing in young Japanese males. It also suggests that these subjects may be increasingly susceptible to atherosclerotic cardiovascular disease with increasing age.

Rapid westernization of children's blood cholesterol in 3 countries: evidence for nutrient-gene interactions?

The aim of this study was to examine potential factors that modify blood cholesterol among children in countries in which dietary and lifestyle habits are becoming westernized. Population data on serum total and lipoprotein cholesterol, anthropometric indexes, and dietary intake were reviewed and compared for children aged 1-18 y from Japan, Spain, and the United States. The data show that total serum cholesterol in Japanese and Spanish children recently exceeded the 75th percentile for US children, primarily reflecting LDL cholesterol, although both LDL and HDL cholesterol contributed. Adiposity indexes do not explain the trends observed. Total and saturated fat intakes increased substantially in both Japan and Spain but in Japan are still lower than intakes in the United States. The Hegsted equation was used to relate differences in serum cholesterol to dietary fat intake. Changes in total serum cholesterol followed established dietary correlations among children in Spain, but not in Japan. Serum cholesterol in Japanese children was predicted to be 0.20-0.32 mmol/L lower than in US children; actual concentrations were considerably higher. These results suggest that a rapid westernization of children's blood cholesterol concentrations has occurred in Japan and Spain. Changes in fat intake predict changes in blood cholesterol in Spain, but not in Japan. Differences in genetic response to diet in certain populations, such as the Japanese, may explain higher blood cholesterol concentrations with lower fat intakes compared with the United States.

Coronary atherosclerosis in youths in Kyushu Island, Japan: histological findings and stenosis

We histologically examined the coronary arteries of 52 autopsied cases of the youths (3 to 39 years of age, mean 28.5 years) in Kyushu island, Japan, without clinical events of coronary artery diseases. The coronary artery specimens were taken from the proximal portions of the right coronary artery (Seg. 1), the left anterior descending artery (Seg. 6), and the macroscopically most stenotic region (ST). Atherosclerotic lesions were histologically classified into four types: concentric fibrous, eccentric fibrous, concentric lipid rich, or eccentric lipid-rich type. The degrees of stenosis (< 25%, 25-50%, 50 75%, > 75%) were morphometrically evaluated. The majority of coronary arteries with under 50% stenosis were of the concentric fibrous type. Lipid-rich types of coronary atherosclerosis increased in the coronary arteries with over 50% stenosis and were observed in the Seg. 6 and ST, while 70% of Seg. 1 lesions with over 50% stenosis were of a fibrous type. Serum cholesterol levels of patients with a lipid rich type of coronary atherosclerosis were significantly higher than those with a fibrous type. These results suggested that the early stage of coronary atherosclerosis in Japanese youths is mainly of a concentric fibrous type, which later develops to a lipid rich type. Hypercholesterolemia would promote the progression of atherosclerosis.

Prevention of cardiovascular risk factors in the first place

Cardiovascular disease (CVD) prevention can address the major risk factors-blood lipids, blood pressure, and smoking-and their determinants throughout the lifespan, with approaches varying according to age and risk. The Task Force on Research in Epidemiology and Prevention of Cardiovascular Diseases gave new impetus to the concept of early intervention: Their highest priority in CVD prevention was "to prevent the development of CVD risk in the first place." Six issues follow: (1) the relation between "primordial prevention" of CVD and "prevention of the risk factors in the first place"; (2) the place of youth in context with older and younger age groups; (3) the importance of bridging institutional gaps between youth and adulthood; (4) the need to strengthen the scientific base linking the major risk factors (e.g., blood cholesterol concentration) with their determinants; (5) the value of rate of change in risk factors with age, and not only incidence of "treatable" levels of risk factors, as an outcome in assessing interventions; and (6) the role and appropriate design strategies for both observational and intervention studies. It is time for a radical expansion of our investment in preventing the risk factors in the first place.

Lipoprotein modification and atherosclerosis in aging

The development of extensive atherosclerosis of major arteries of the heart, brain, and lower extremities is a particularly frequent problem in elderly individuals and is responsible for the majority of the cardiovascular morbidity and mortality in this population. Although the frequency and severity of this problem is well recognized, there has been relatively little investigation of the effects of aging on the development of atherosclerosis. Work by a number of investigators over the last 10-15 years has demonstrated that modifications of lipoproteins, resulting from oxidative stress, glycoxidation, formation of AGE, or other processes may play an important role in atherosclerosis. As described in this review, the aging process may enhance lipoprotein modification and atherosclerosis in several ways. Conditions such as hypertension, diabetes, and menopause all increase in frequency with advancing age and may contribute both directly and indirectly to lipoprotein modification and vascular injury.Additionally, in some studies of older animals and humans, there seems to be evidence for greater in vivo oxidative stress. Whether this is a specific consequence of aging and associated medical conditions, or related to differences in dietary fatty acid or antioxidant content or other lifestyle differences is currently unknown. One important consequence of this may be enhanced susceptibility of lipoproteins to oxidation. Additional study of lipoprotein modifications associated with aging is clearly needed, and may provide new insight and solutions to the common problem of atherosclerosis in the elderly.

Antioxidant vitamin levels in plasma and low density lipoprotein of obese girls

To investigate the antioxidant status of obese children, we analyzed beta-carotene and alpha-tocopherol levels in plasma and low density lipoprotein (LDL). We also analyzed the fatty acid composition of LDL as a substrate for oxidative stress. The plasma beta-carotene and alpha-tocopherol levels were relatively lower in obese girls than in normal controls. However, the plasma alpha-tocopherol/lipids ratio was significantly lower in obese girls than in normal controls. Both LDL beta-carotene and LDL alpha-tocopherol levels were significantly lower in obese girls than in normal controls, although no obvious differences were observed in plasma levels. In obese girls LDL contained more polyunsaturated fatty acid (PUFA) compared with normal controls. When the peroxidizability index (PI) was calculated to estimate the susceptibility of lipids to oxidative stress, obese girls had significantly higher PI values than normal controls. Both the LDL beta-carotene/PI ratio and the LDL alpha-tocopherol/PI ratio were significantly lower in obese girls than in normal controls. These results indicate the increased susceptibility of LDL to oxidative stress in obese girls which may promote atherosclerosis later in life.

A study of the development of atherosclerosis in childhood and young adults: risk factors and the prevention of progression in Japan and the USA. The Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group

Coronary heart disease (CHD), one of the prevalent results of atherosclerotic disease, has been a leading cause of death in many Western countries for several decades, and now is the second most prevalent cause of death in Japan. Thus attention must also be paid to atherosclerosis in Japan. While there has been a remarkable reduction in the mortality rate from CHD in some Western countries, an undesirable stabilized mortality rate has recently been reported by the government of Japan. This report emphasises the importance of preventing atherosclerosis at an early stage from the viewpoint of cardiovascular pathology, using evidence from statistical data derived from autopsied cases in Japan and the USA.

Enhanced expression of tissue factor activity in the atherosclerotic aortas of cholesterol-fed rabbits

Tissue factor (TF) is an initiation cofactor of the extrinsic pathway of coagulation. Although the overexpression of TF antigen and mRNA have been previously demonstrated in atherosclerotic lesions using both immunohistochemical and in situ hybridization techniques, it still remains unclear as to whether TF activity is overexpressed in atherosclerotic plaque in vivo. In thoracic aortas obtained from cholesterol-fed rabbits for 10-20 weeks, the TF-mediated activation of factor X was quantitatively assessed on the intimal surface of the aortas ex vivo using a chromogenic substrate S-2222 and the findings were then compared with the immunohistochemical distribution of TF antigen. Non-atherosclerotic intimas showed only a weak amount of TF activity, while the adventitia contained a significantly high amount of activity. In the atherosclerotic intimas where TF antigen was overexpressed by foamy and non-foamy macrophages and smooth muscle cells but not by endothelial cells, TF activity was apparently enhanced to a level similar to that in the adventitia. Scanning electron microscopy revealed a perturbation of the intimal surface of the atherosclerotic aorta. These findings suggest that TF activity is apparently enhanced in subendothelial atherosclerotic lesions and, therefore, endothelial denudation, which results in the exposure of active TF to flowing blood, leads to thrombosis and its sequelae in atherosclerotic lesions.

Intimal thickening and fragmentation of the internal elastic lamina in the mesenteric arteries

To evaluate the intimal thickness and continuity of the internal elastic lamina (IEL) in the mesenteric arteries, proximal segments of the coeliac artery (CA), superior mesenteric artery (SMA) and inferior mesenteric artery (IMA) were studied light microscopically in 123 consecutive postmortem examinations. The mean age of the subjects was 62 years. Arterial segments were fixed in formalin, embedded in paraffin blocks, sectioned, and stained with Masson's trichrome. Fifty-one per cent of the samples examined showed at least minimal intimal thickening. The occurrence of significant luminal narrowing increased with age. We found a positive correlation between defects in the IEL and thickness of the intima in the mesenteric arteries, which is in harmony with previous observations showing marked fragmentation of the IEL in atherogenesis.

Serum cholesterol levels in school-aged Japanese children: the Hisayama study

Hypercholesterolemia has been known to be an important factor in the development of atherosclelosis. Blood cholesterol screening and related health education in children, however, have not yet been widely practiced in Japan. From 1985 to 1990, blood samples were obtained from 5825 school children aged 6 to 14 years residing in Hisayama, Japan. The mean total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were determined. The mean TC levels ranged from 155 to 172 mg/dL for boys and from 156 to 170 mg/dL for girls, peaking at 9 years for both sexes. The TG levels also tended to increase gradually and to peak at 11 years for both sexes. The tendency for TG levels to be higher was much clearer than in US children and adolescents. The HDL-C levels were highest at 9 years of age for both sexes and the LDL-C levels also tended to peak at 9 years of age for boys and at 8 years of age for girls. Atherogenic Indices [(TC-HDL-C)/HDL-C] ranged from 1.7 to 1.9 for boys and 1.8 to 2.0 for girls. As the cholesterol level of Japanese children would be expected to rise steadily reflecting their westernized lifestyle, preventive programes on a nationwide base including health education at school environments should be emphasized.

Lipoprotein (a) and apolipoprotein A-1 and B in schoolchildren whose grandparents had coronary and cerebrovascular events: a preliminary study of 12-13 year old Japanese children

The aim of this study was to evaluate the relationship between the serum levels of lipoprotein (a) [Lp (a)] and apolipoproteins (apo A-1 and apo B) in schoolchildren with a history of coronary and cerebrovascular events in their grandparents. We measured serum concentrations of Lp (a) and apoliproteins immunochemically in 289 schoolchildren aged 12-13 years and questioned parents about coronary and cerebrovascular events in the children's grandparents. In boys and girls, mean +/- s.d. levels of apo A-1, apo B and Lp (a) were 134 +/- 20.3 and 136 +/- 17.4 mg/dL, 61 +/- 16 and 66 +/- 15 mg/dL and 12.5 +/- 15.3 and 12.5 +/- 15.1 mg/dL, respectively. There were no significant sex differences in the levels of apo A-1, apo B, and Lp (a). The Lp (a) levels (mean +/- s.d., 12.5 +/- 15.2 mg/dL; median 7.5 mg/dL, n = 289) were not affected by other variables. The Lp (a) distribution was strongly positively skewed and 75% of schoolchildren had very low levels. In the total 289 schoolchildren, thirty-two grandparents who had had coronary vascular events (21 myocardial infarction, 11 angina pectoris) and twenty-three grandparents who had had cerebrovascular events were recorded. By the boxplot statistical analysis, no difference was found in Lp (a) levels in children whose grandparents had myocardial infarction compared with those whose grandparents had no such history, or compared with those whose grandparents had suffered cerebrovascular events.(ABSTRACT TRUNCATED AT 250 WORDS)

Environmental and genetic risk factors in early human atherogenesis: lessons from the PDAY study. Pathobiological Determinants of Atherosclerosis in Youth

A multi-institutional study 'Pathobiological Determinants of Atherosclerosis in Youth' (PDAY) was initiated to document the natural history of atherosclerosis, its relationship to risk factors, and pathobiology of lesion development in young subjects. Pathology laboratories in nine centers collected arteries and tissues from over 2000 persons from 15 through 34 years of age whose deaths were attributed to homicides, accidents, or suicides. Arteries were evaluated for lesions, and risk factors were analyzed in a central laboratory. Post-mortem risk factors included serum lipoproteins, serum thiocyanate (smoking), glycohemoglobin (diabetes), thickness of panniculus adiposus (obesity), small renal artery changes (hypertension) and apoprotein isoforms. This study documents the development of atherosclerosis at an early age. It also shows that the recognized risk factors for coronary heart disease are associated with lesion development in the arteries of these young subjects. The PDAY study has a counterpart in Japan where the development of atherosclerosis has been studied in young subjects. This Japanese study, in a population in which coronary heart disease has not yet become a major epidemic, has findings quite similar to the findings from the PDAY study. Studies of atherosclerosis in both Japan and the USA provide strong justification for reducing risk factors in young persons.

Coronary and cerebrovascular atherosclerosis: two aspects of the same disease or two different pathologies?

Cerebrovascular and coronary disease are characterized by some common aspects. Indeed the same risk factors relate to coronary heart disease and to cerebrovascular disease. However, there may be differences in the pathogenesis of atherosclerotic lesions in coronary and cerebral arteries. In fact some populations are characterized by a high incidence of ischaemic stroke and a low incidence of myocardial infarction, while in other populations there is an opposite trend. These differences could be explained on the basis of: genetic risk factors; a different prevalence of risk factors; a different reactivity of the coronary and cerebral arteries to risk factors; anatomical differences concerning coronary and extracranial cerebral arteries with respect to intracranial cerebral arteries. Atherosclerosis is undoubtedly a systemic disorder and its genetic and environmental causal factors are only partly known. The variable incidence of cerebrovascular and coronary heart disease in the same population or in different populations as well as the different nature of atherosclerotic plaques are probably related to the different prevalence of the causal factors, even though these may not always be identified.

Corticosteroids: do they damage the cardiovascular system?

Since their introduction for the treatment of rheumatoid arthritis, corticosteroids have become widely used as effective agents in the control of inflammatory diseases. Although there have been undoubted benefits upon mortality in diseases such as systemic lupus erythematosus, many patients survive only to suffer a high incidence of premature atherosclerosis. There is also evidence of increased rates of vascular mortality in other corticosteroid-treated diseases, such as rheumatoid arthritis, reversible airways obstruction and transplant recipients. Possible mechanisms of damage include elevated blood pressure, impaired glucose tolerance, dyslipidaemia, and imbalances in thrombosis and fibrinolysis. This paper reviews the clinical evidence supporting the contention that there is an excess cardiovascular mortality in steroid-treated patients and the underlying mechanisms, and points to further areas of research.