Cardiovascular risk assessment and cholesterol management in adolescents: getting to the heart of the matter

Associations between serum selenium and serum lipids in adolescents aged 12-19: A cross-sectional study

BACKGROUND

Selenium is an essential trace element in the human body and is important in lipid metabolism. Previous studies on the relationship between selenium and serum lipids were almost conducted in adults, and the research conclusions were inconsistent. Evidence linking selenium and lipids in adolescents is very limited. As an important stage of growth and development, studying the effects of trace elements on the body during adolescence is meaningful.

OBJECTIVE

This study examined the association between serum selenium and serum lipids in adolescents aged 12-19.

METHODS

This cross-sectional study analyzed 2209 adolescents aged 12-19 years from NHANES 2011 to 2016. Multiple linear regression analyses were performed to evaluate selenium's association with serum lipids (containing TC, TG, LDL-C, and HDL-C). Moreover, a generalized additive model (GAM) and a fitted smoothing curve (penalized spline method) were conducted to explore the exact curve shape between them.

RESULTS

In the fully adjusted model, it showed a positive association between selenium and TC, TG, LDL-C [TC (β = 0.144 (, 95 % CI (0.084, 0.204), P < 0.001), TG (β = 0.285, 95 % CI (0.134, 0.437), P < 0.001), LDL-C (β = 0.098, 95 % CI (0.022, 0.174), P = 0.011)], whereas a negative association [(β = -0.031, 95 % CI (-0.054, - 0.009), P = 0.006)] between Se and HDL-C. Subgroup analysis showed that the above associations were more significant in females aged 12-19 (P for trend < 0.05). Furthermore, linear associations were performed in Se between TC and LDL-C.

CONCLUSION

This is the first study to find evidence demonstrating associations between serum Se and serum lipids in adolescents aged 12-19. The validation of our findings will require further research.

Personalized Intervention Based on Early Detection of Atherosclerosis: JACC State-of-the-Art Review

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide and challenges the capacity of health care systems globally. Atherosclerosis is the underlying pathophysiological entity in two-thirds of patients with CVD. When considering that atherosclerosis develops over decades, there is potentially great opportunity for prevention of associated events such as myocardial infarction and stroke. Subclinical atherosclerosis has been identified in its early stages in young individuals; however, there is no consensus on how to prevent progression to symptomatic disease. Given the growing burden of CVD, a paradigm shift is required-moving from late management of atherosclerotic CVD to earlier detection during the subclinical phase with the goal of potential cure or prevention of events. Studies must focus on how precision medicine using imaging and circulating biomarkers may identify atherosclerosis earlier and determine whether such a paradigm shift would lead to overall cost savings for global health.

Sociodemographic inequalities in cardiovascular risk factors among adolescents from indigenous areas in Chiapas, Mexico

This study was aimed to determine the prevalence of cardiovascular risk factors among different sociodemographic groups of adolescents from indigenous communities in Chiapas, Mexico. A cross-sectional prevalence study was performed in urban and rural communities in the Tzotzil-Tzeltal and Selva regions of Chiapas. A sample of 253 adolescents was studied, of whom 48% were girls and 52% were boys. A descriptive analysis of quantitative variables was performed using measures of central tendency and dispersion. The prevalence of cardiovascular risk factors stratified by sex, geographical area, years of schooling, and ethnicity of the mothers was estimated. The prevalence of cardiovascular risk factors was analyzed in relation to the sociodemographic characteristics of the study population. Low HDL-c (51%) was the predominant cardiovascular risk factor. Girls had a higher prevalence of abdominal obesity, hypertriglyceridemia, and borderline total cholesterol than boys. High diastolic blood pressure was more prevalent in boys. Adolescents from urban areas had a higher prevalence of overweight/obesity and insulin resistance than adolescents from rural areas. The prevalence of overweight/obesity and abdominal obesity was higher in adolescents whose mothers had ≥ 7 years of schooling compared with adolescents with less educated mothers. Differences by maternal ethnicity also influenced the prevalence of insulin resistance. Among the main findings, this study associated sociodemographic and geographical inequalities with cardiovascular risk factors. Promoting a healthy lifestyle for this young population is absolutely necessary to prevent cardiovascular diseases in adulthood.

Effect of Tannins on Cholesterol Content and Its Oxidation in Egg Pasta as Related to Different Pasta Shapes

Egg pasta contains high amount of cholesterol, that upon oxidation, generates oxysterols (COPs), which play a key role in the onset of several human diseases. In this study, the effect of two tannins (esters of ellagic acid, A; esters of gallic acid, B) at three different concentrations (0.25%, 0.50%, 1.00%) was tested in egg pasta considering two different pasta shapes (squared, S; rectangular, F). When tannin B was added, the total phenolic content (TPC) in fresh pasta increased (p < 0.01) and after cooking its content was greater than those obtained with tannin A. The pasta shape affected the presence of cholesterol; its amount in uncooked F shape samples (27.67 ± 0.28 mg/g pasta) was higher than that found in S shape (21.18 ± 0.49 mg/g pasta). In addition, tannin B significantly (p < 0.01) increased the presence of cholesterol in the cooking water (up to 1.04 ± 0.05 μg/mL), in particular in S pasta shape. Tannin B was also greater than tannin A to reduce the content of COPs in fresh egg pasta, while the cooking process did not impact (p > 0.05) the oxidation of cholesterol. The results suggest that tannin B could be applied in the formulation of egg pasta as a strategy for reducing the content of cholesterol and its oxidation products.

Machine learning improves risk stratification of coronary heart disease and stroke

BACKGROUND

Coronary heart disease (CHD) and cerebral ischemic stroke (CIS) are two major types of cardiovascular disease (CVD) that are increasingly exerting pressure on the healthcare system worldwide. Machine learning holds great promise for improving the accuracy of disease prediction and risk stratification in CVD. However, there is currently no clinically applicable risk stratification model for the Asian population. This study developed a machine learning-based CHD and CIS model to address this issue.

METHODS

A case-control study was conducted based on 8,624 electronic medical records from 2008 to 2019 at the Tongji Hospital in Wuhan, China. Two machine learning methods (the random down-sampling method and the random forest method) were integrated into 2 ensemble models (the CHD model and the CIS model). The trained models were then interpreted using Shapley Additive exPlanations (SHAP).

RESULTS

The CHD and CIS models achieved good performance with the areas under the receiver operating characteristic curve (AUC) of 0.895 and 0.884 in random testing, and 0.905 and 0.889 in sequential testing, respectively. We identified 4 common factors between CHD and CIS: age, brachial-ankle pulse wave velocity, hypertension, and low-density lipoprotein cholesterol (LDL-C). Moreover, carcinoembryonic antigen (CEA) was identified as an independent indicator for CHD.

CONCLUSIONS

Our ensemble models can provide risk stratification for CHD and CIS with clinically applicable performance. By interpreting the trained models, we provided insights into the common and unique indicators in CHD and CIS. These findings may contribute to a better understanding and management of risk factors associated with CVD.

Tools for Assessing Cardiovascular Disease Risk Factors in Underserved Young Adult Populations: A Systematic Review

Cardiovascular disease (CVD, i.e., disease of the heart and blood vessels) is a major cause of death globally. Current assessment tools use either clinical or non-clinical factors alone or in combination to assess CVD risk. The aim of this review was to critically appraise, compare, and summarize existing non-clinically based tools for assessing CVD risk factors in underserved young adult (18–34-year-old) populations. Two online electronic databases—PubMed and Scopus—were searched to identify existing risk assessment tools, using a combination of CVD-related keywords. The search was limited to articles available in English only and published between January 2008 and January 2019. Of the 10,383 studies initially identified, 67 were eligible. In total, 5 out of the 67 articles assessed CVD risk in underserved young adult populations. A total of 21 distinct CVD risk assessment tools were identified; six of these did not require clinical or laboratory data in their estimation (i.e., non-clinical). The main non-clinically based tools identified were the Heart Disease Fact Questionnaire, the Health Beliefs Related to CVD-Perception measure, the Healthy Eating Opinion Survey, the Perception of Risk of Heart Disease Scale, and the WHO STEPwise approach to chronic disease factor surveillance (i.e., the STEPS instrument).

Impact of short-term change of adiposity on risk of high blood pressure in children: Results from a follow-up study in China

This study aimed to examine the impact of short-term adiposity change on risk of high blood pressure (HBP), and to assess the low limit range of body mass index (BMI) and waist-to-height ratio (WHtR) reduction proposed to decrease the HBP risk in children. Children were longitudinally surveyed at baseline and after a short-term follow-up. General obesity (GOB) is categorized by age and gender-specific BMI cut-off points, abdominal obesity (AOB) by WHtR. Logistic regression model was used to estimate relations between adiposity change and HBP risk with adjustment of covariates. A total of 28,288 children (median of baseline age:10 years) were involved with follow-up of 6.88±1.20 months. After the follow-up, 9.4% of the children had persistent general obesity (GOB), 2.8% converted from GOB to non-GOB, 0.9% had newly developed GOB. When compared with children remained non-GOB, children with continuous GOB status, newly developed GOB, converting from GOB to non-GOB had 5.03-fold (95%CI: 4.32~5.86), 3.35-fold (95%CI: 1.99~5.65), 2.72-fold (2.03~3.63) HBP risk, respectively. Similar findings were observed for abdominal obesity (AOB). Reduction of 0.21–0.88 kg/m² of baseline BMI (0.86–3.59%) or 0.009–0.024 of baseline WHtR (1.66–4.42%) in GOB or AOB children, respectively, was associated with significant decrease in HBP risk. Children with persistent obesity, newly developed obesity, or converting from obese to non-obese had significantly higher HBP risk. For children with GOB or AOB, reduction of <3.6% in BMI or <4.5% in WHtR could decrease the HBP risk.

Developing implementation strategies to improve uptake of guideline-recommended treatments for individuals with familial hypercholesterolemia: A protocol

BACKGROUND

Familial hypercholesterolemia (FH) affects more than one million Americans, and most individuals have not been formally diagnosed with the condition. Individuals with FH have markedly elevated serum low-density lipoprotein cholesterol (LDL-C) levels from birth that substantially increase their risk for early-onset cardiovascular (CV) events. Guideline-recommended treatments exist to lower LDL-C and reduce the risk of CV events in individuals with FH and hypercholesterolemia. This study seeks to address a significant gap in the care of individuals with FH by systematically developing an effective approach to increase the adoption of guideline-recommended treatments for FH.

METHODS

This developmental study will consist of three aims: 1) determine the barriers to and facilitators of treatment of FH; 2) develop a list of potential implementation strategies to promote the adoption of guideline-recommended treatment of individuals with FH, and 3) pilot one implementation strategy from Aim 2 in one health care system to evaluate implementation outcomes of the strategy. The Practical, Robust Implementation and Sustainability Model will guide this project, including the development of interview questions, implementation strategies, and evaluation of the implementation strategy. The implementation outcomes include: of individuals targeted by the implementation strategy, how many are impacted by it (reach), measure the change in knowledge, attitude, and behavior that is impacted by the implementation strategy (effectiveness), in settings targeted by the implementation strategy, how many adopt it (adoption), and fidelity and cost of the implementation strategy (implementation). Data sources will include electronic health records, administrative databases, surveys, and semi-structured interviews.

DISCUSSION

The inclusion of patient and organizational stakeholder experiences is a critically important step in developing efficient and effective implementation strategies. Additionally, perspectives from a variety of geographic areas and cultural perspectives should increase feasibility and fidelity of the interventional approach to improve adoption of guideline-recommended practices for FH care.

Healthcare Utilization and Patients' Perspectives After Receiving a Positive Genetic Test for Familial Hypercholesterolemia

BACKGROUND

The MyCode Community Health Initiative (MyCode) is returning actionable results from whole exome sequencing. Familial hypercholesterolemia (FH) is an inherited condition characterized by premature cardiovascular disease.

METHODS

We used multiple methods to assess care in 28 MyCode participants who received FH results. Chart reviews were conducted on 23 individuals in the sample and 7 individuals participated semistructured interviews.

RESULTS

Chart reviews for 23 individuals with a Geisinger primary care provider found that 4 individuals (17% of 23) were at LDL-C (low-density lipoprotein cholesterol) goal (of either LDL-C <100 mg/dL for primary prevention and LDL-C <70 mg/dL for secondary prevention) and 17 individuals (74% of 23) were prescribed lipid-lowering therapy before genetic result disclosure. After disclosure of the genetic test result, 5 individuals (22% of 23) met their LDL-C goal and 18 individuals (78% of 23) were prescribed lipid-lowering therapy. Follow-up care about this result was not documented for 4 individuals (17% of 23). Changes to intensity of medication management were made for 8 individuals (47% of 17 individuals previously prescribed lipid-lowering therapy). Interviewed individuals (n=7) were not surprised by their result as all knew they had high cholesterol; however, individuals did not seem to discern FH as a separate condition from their high cholesterol.

CONCLUSIONS

Among individuals receiving genetic diagnosis of FH, >25% had no changes to lipid-lowering therapy, despite not being at LDL-C goal and learning their high cholesterol is related to a genetic condition requiring more aggressive treatment. Individuals and clinicians may have an inadequate understanding of FH as a distinct condition requiring enhanced medical management.

Using Cluster Analysis to Identify Subgroups of College Students at Increased Risk for Cardiovascular Disease

BACKGROUND AND PURPOSE

 To examine the co-occurrence of cardiovascular risk factors and cluster subgroups of college students for cardiovascular risks.

METHODS

A cross sectional descriptive study was conducted using co-occurrence patterns and hierarchical clustering analysis in 158 college students.

RESULTS

The top co-occurring cardiovascular risk factors were overweight/obese and hypertension (10.8%, n = 17). Of the total 34 risk factors that co-occurred, 30 of them involved being overweight/obese. A six-cluster-solution was obtained, two clusters displayed elevated levels of lifetime and 30-year cardiovascular disease risks.

CONCLUSIONS

The hierarchical cluster analysis identified that single White males with a family history of heart disease, overweight/obese, hypertensive or diabetes, and occasionally (weekly) consumed red meat, take antihypertensive medication, and hyperlipidemia were considered the higher risk group compared to other subgroups.

Plasma metabolomics of children with aberrant serum lipids and inadequate micronutrient intake

Blood lipids have served as key biomarkers for cardiovascular disease (CVD) risk, yet emerging evidence indicates metabolite profiling might reveal a larger repertoire of small molecules that reflect altered metabolism, and which may be associated with early disease risk. Inadequate micronutrient status may also drive or exacerbate CVD risk factors that emerge during childhood. This study aimed to understand relationships between serum lipid levels, the plasma metabolome, and micronutrient status in 38 children (10 ± 0.8 years) at risk for CVD. Serum lipid levels were measured via autoanalyzer and average daily micronutrient intakes were calculated from 3-day food logs. Plasma metabolites were extracted using 80% methanol and analyzed via ultra-high-performance liquid chromatography-tandem mass spectrometry. Spearman's rank-order coefficients (rs) were computed for correlations between the following serum lipids [total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides (TG)], 805 plasma metabolites, and 17 essential micronutrients. Serum lipid levels in the children ranged from 128-255 mg/dL for total cholesterol, 67-198 mg/dL for LDL, 31-58 mg/dL for HDL, and 46-197 mg/dL for TG. The majority of children (71 to 100%) had levels lower than the Recommended Daily Allowance for vitamin E, calcium, magnesium, folate, vitamin D, and potassium. For sodium, 76% of children had levels above the Upper Limit of intake. Approximately 30% of the plasma metabolome (235 metabolites) were significantly correlated with serum lipids. As expected, plasma cholesterol was positively correlated with serum total cholesterol (rs = 0.6654; p<0.0001). Additionally, 27 plasma metabolites were strongly correlated with serum TG (rs ≥0.60; p≤0.0001), including alanine and diacylglycerols, which have previously been associated with cardiometabolic and atherosclerotic risk in adults and experimental animals. Plasma metabolite profiling alongside known modifiable risk factors for children merit continued investigation in epidemiological studies to assist with early CVD detection, mitigation, and prevention via lifestyle-based interventions.

Cardiovascular Biomarkers in Association with Dietary Intake in a Longitudinal Study of Youth with Type 1 Diabetes

Despite cardioprotective effects of a healthy diet in the general population, few studies have investigated this relationship in individuals with type 1 diabetes, who are at elevated risks of cardiovascular disease (CVD) due to hyperglycemia. The objective of this study was to examine the association of CVD biomarkers with overall diet quality, as measured by the Healthy Eating Index-2015 (HEI-2015), and its dietary components in youth with type 1 diabetes. Youth with type 1 diabetes (n = 136, 8–16.9 years) were enrolled in an 18-month behavioral nutrition intervention trial. Dietary intake from three-day diet records, CVD biomarkers (total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C); triglycerides (TG), C-reactive protein (CRP), 8-iso-prostaglandin-F2alpha (8-iso-PGF_2α), systolic and diastolic blood pressure (SBP and DBP, respectively), and glycated hemoglobin (HbA1c) were assessed at baseline, 6, 12 and 18 months. Linear mixed-effects models estimated associations of dietary intake with CVD biomarkers, adjusting for HbA1c and other covariates. Separate models estimated associations of time-varying change in dietary intake with time-varying change in CVD biomarkers. HEI-2015 was not associated with CVD biomarkers, but whole grain intake was inversely associated with TC, HDL-C and DBP, and a greater increase in whole fruit intake was associated with lower DBP. Added sugar, saturated fat and polyunsaturated fat were positively related to serum TG, HDL-C, and DBP, respectively. Findings suggest that the intake of specific dietary components, including whole grains, whole fruits, added sugar and PUFA, may influence cardiometabolic health in youth with type 1 diabetes, independent of glycemic control.

Reference intervals for serum lipids and prevalence of dyslipidaemia in 6-12-year-old children: The Health Oriented Pedagogical Project (HOPP)

AIMS

Elevated serum lipid concentrations in childhood are thought to be risk factors for the development of cardiovascular disease later in life. The present study aims to provide age- and gender-related reference intervals for total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and non-HDL cholesterol in healthy school children. We also investigated the prevalence of dyslipidaemia using the published criteria for these biomarkers.

METHODS

Venous blood and anthropometric data were collected from 1340 children in the HOPP study, aged between 6 and 12 years. Age- and gender-related reference intervals (2.5th and 97.5th percentiles) were established according to the IFCC recommendations, using the software RefVal 4.10.

RESULTS

Gender differences were observed for total cholesterol and non-HDL cholesterol, but not for HDL cholesterol. Age differences were observed for total cholesterol. The reference intervals were in the range of 3.1-5.9 mmol/L for total cholesterol, 1.0-2.4 mmol/L for HDL cholesterol and 1.4-4.2 mmol/L for non-HDL cholesterol. Dyslipidaemia prevalence was as follows: increased TC 9.6%, decreased HDL 1.6%, and increased non-HDL 5.6%.

CONCLUSIONS

Age- and gender-related reference intervals in a Norwegian population are similar to those reported in other countries. The prevalence of dyslipidaemia among Norwegian children is significant, emphasising the importance of appropriate reference intervals in clinical practice.

Navy Bean and Rice Bran Intake Alters the Plasma Metabolome of Children at Risk for Cardiovascular Disease

Abnormal cholesterol in childhood predicts cardiovascular disease (CVD) risk in adulthood. Navy beans and rice bran have demonstrated efficacy in regulating blood lipids in adults and children; however, their effects on modulating the child plasma metabolome has not been investigated and warrants investigation. A pilot, randomized-controlled, clinical trial was conducted in 38 children (10 ± 0.8 years old) with abnormal cholesterol. Participants consumed a snack for 4 weeks containing either: no navy bean or rice bran (control); 17.5 g/day cooked navy bean powder; 15 g/day heat-stabilized rice bran; or 9 g/day navy beans and 8 g/day rice bran. Plasma metabolites were extracted using 80% methanol for global, non-targeted metabolic profiling via ultra-high performance liquid-chromatography tandem mass spectrometry. Differences in plasma metabolite levels after 4 weeks of dietary intervention compared to control and baseline were analyzed using analysis of variance and Welch's t-tests (p ≤ 0.05). Navy bean and/or rice bran consumption influenced 71 plasma compounds compared to control (p ≤ 0.05), with lipids representing 46% of the total plasma metabolome. Significant changes were determined for 18 plasma lipids in the navy bean group and 10 plasma lipids for the rice bran group compared to control, and 48 lipids in the navy bean group and 40 in the rice bran group compared to baseline. These results support the hypothesis that consumption of these foods impact blood lipid metabolism with implications for reducing CVD risk in children. Complementary and distinct lipid pathways were affected by the diet groups, including acylcarnitines and lysolipids (navy bean), sphingolipids (rice bran), and phospholipids (navy bean + rice bran). Navy bean consumption decreased free fatty acids associated with metabolic diseases (palmitate and arachidonate) and increased the relative abundance of endogenous anti-inflammatory lipids (endocannabinoids, N-linoleoylglycine, 12,13-diHOME). Several diet-derived amino acids, phytochemicals, and cofactors/vitamins with cardioprotective properties were increased compared to control and/or baseline, including 6-oxopiperidine-2-carboxylate (1.87-fold), N-methylpipecolate (1.89-fold), trigonelline (4.44- to 7.75-fold), S-methylcysteine (2.12-fold) (navy bean), salicylate (2.74-fold), and pyridoxal (3.35- to 3.96-fold) (rice bran). Findings from this pilot study support the need for investigating the effects of these foods for longer durations to reduce CVD risk.

TRIAL REGISTRATION

clinicaltrials.gov (identifier NCT01911390).

Transitioning from pediatric to adult health care with familial hypercholesterolemia: Listening to young adult and parent voices

BACKGROUND

Young adults with familial hypercholesterolemia (FH) are at a critical period for establishing behaviors to promote future cardiovascular health.

OBJECTIVE

To examine challenges transitioning to adult care for young adults with FH and parents of FH-affected young adults in the context of 2 developmental tasks, transitioning from childhood to early adulthood and assuming responsibility for self-management of a chronic disorder.

METHODS

Semistructured, qualitative interviews were conducted with 12 young adults with FH and 12 parents of affected young adults from a pediatric subspecialty preventive cardiology program in a northeastern academic medical center. Analyses were conducted using a modified grounded theory framework.

RESULTS

Respondents identified 5 challenges: (1) recognizing oneself as a decision maker, (2) navigating emerging independence, (3) prioritizing treatment for a chronic disorder with limited signs and symptoms, (4) managing social implications of FH, and (5) finding credible resources for guidance. Both young adults and parents proposed similar recommendations for addressing these challenges, including the need for family and peer involvement to establish and maintain diet and exercise routines and to provide medication reminders. Systems-level recommendations included early engagement of adolescents in shared decision-making with health care team; providing credible, educational resources regarding FH; and using blood tests to track treatment efficacy.

CONCLUSION

Young adults with FH transitioning to adult care may benefit from explicit interventions to address challenges to establishing healthy lifestyle behaviors and medication adherence as they move toward being responsible for their medical care. Further research should explore the efficacy of recommended interventions.

Novel pharmacotherapies of familial hyperlipidemia

Familial hyperlipidemia is an inherited metabolic disorder characterized by elevated lipid and/or lipoprotein levels in the blood. Despite improvements in lipid-lowering therapy during the last decades, it still remains a substantial contributor to the incidence of cardiovascular disease since patients on current conventional therapies do not achieve their target LDL-cholesterol levels. With a view to lower LDL-cholesterol levels, a number of new therapeutic strategies have been developed over recent years. In this review, we provide an overview of these treatment options that are currently in clinical development and may offer alternative or adjunctive therapies for this high-risk population.

Hypercholesterolemia among apparently healthy university students

BACKGROUND

Hypercholesterolemia (HC) is a major risk factor in the development of coronary heart disease (CHD). Serum cholesterol is directly related to complications and mortalities associated with heart diseases. There are a few studies that describe HC among youths in the Arab Gulf countries. We sought to evaluate HC among young healthy university students to assess their risk of developing CHD.

METHODS

Lipid profile of 166 students between the ages of 16-30 years (Mean: 20.49±2.96) were examined and blood glucose, total protein, albumin, thyroid stimulating hormone (TSH) and the inflammation marker high sensitivity CRP (hsCRP) were determined. Each volunteer filled a questionnaire about her/his lifestyle and personal and family medical histories and height and weight were measured to determine body mass index (BMI). The data were analyzed using SPSS version 17. Chi-Square was used to determine the relation between categorical variables. A p-value <0.05 was considered statistically significant.

RESULTS

According to the American Heart Association criteria, 44 (26.5%) students were identified with primary hypercholesterolemia (PHC) in the first testing round. After proper health counseling, the same tests were repeated after 2-3 weeks in all 44 hypercholesterolemic students. We found only 26 (15.6%) of them to be hypercholesterolemic. There was a significant relation between high total cholesterol (TC) and high TC/HDLC, as well as high or very high hsCRP and high TC/HDLC (both, p<0.001). Males tend to have higher TC/HDLC and hsCRP than females (both p0.002 and 0.005, respectively). Family history of CHD was found in 8 students and obesity was recorded in 5 volunteers.

CONCLUSION

The results necessitate further studies in determining the cause of PHC. We predict a genetic element contributing to the high percentage of PHC in the current study.

Coronary artery calcification progression in asymptomatic individuals with initial score of zero

The aim of this study is to determine the progression of coronary artery calcification (CAC) using electron beam computed tomography (CT) when the initial CAC score (CACS) is zero and to determine the best interval to repeat a CAC scan. We studied 388 individuals with zero CACS (308 males; mean age: 48.8 ± 8.26 years) who underwent 2 consecutive CT scans in a period of at least 12 months apart. The interscan period was 2.99 ± 1.35 years (range: 1-6 years). Three-quarters of the individuals (75%) did not develop any CAC progression, 20.87% presented CAC progression of 1 to 10, 3.6% had 11 to 50, whereas only 0.51% had >50. The average time of new CAC development was 4.2 ± 1.1 years. Individuals with CAC progression presented higher incidence of hypertension, diabetes mellitus, hypercholesterolaemia and higer frequency of male gender than those with without CAC changes (p<0.02). No cardiac events occurred during the follow-up period.

Should children dive with self-contained underwater breathing apparatus (SCUBA)?

Diving with self-contained underwater breathing apparatus (SCUBA) has become a popular recreational activity in children and adolescents. This article provides an extensive review of the current literature.

CONCLUSIONS

Medical contraindications to SCUBA diving for adults apply to children and adolescents, too, but must be adapted. Additional restrictions to the fitness to dive must apply to both, children and adolescents. Children should always be accompanied by a trained adult when diving.

Management of familial hypercholesterolaemia in children and adolescents

Familial hypercholesterolaemia is a disorder of low-density lipoprotein (LDL) cholesterol metabolism, which is associated with the onset of vascular changes associated with coronary heart disease in childhood. This disorder has co-dominant transmission with a prevalence of one in 500 in the general population. Cascade screening is the most effective method of identifying children. Children in the at-risk group should have their cholesterol levels checked between the age of 2 and 10 years. Children with LDL cholesterol levels ≥ 3.4 mmol/L are likely to suffer from this disorder, although at this level there is a significant false positive rate. Molecular genetic testing is available for the LDL receptor gene, APOB gene and the PCSK9 gene. This is the most specific test for familial hypercholesterolaemia but has a false negative rate of 20-50%. Once diagnosed, treatment should be considered in children with an LDL cholesterol level ≥ 4.9 mmol/L. If the child has two other risk factors or a positive family history, this threshold should be lowered to ≥4.1 mmol/L. Guidelines recommend that treatment should be commenced by the age of 10 years, although some advise waiting until menarche in females. Statin therapy is currently recommended as first line treatment. Randomised placebo trials have shown that statin therapy reduces LDL cholesterol levels by 25% and is not associated with increased risk of adverse events. These are short-term studies, and longer follow-up will be required to definitively prove efficacy and safety.

Paraoxonase 1 protects macrophages from atherogenicity of a specific triglyceride isolated from human carotid lesion

Human atherosclerotic lesions contain oxidized lipids that facilitate further oxidation of macrophages, LDLs, and oxidative stress (OS)-sensitive markers and inhibit the antiatherogenic enzyme paraoxonase 1 (PON1). Our aim was to isolate and identify the oxidizing agent in a human atherosclerotic lesion lipid extract (LLE) and to explore the mechanisms of oxidation and of PON1's effect on the oxidizing agent. Of the five main fractions separated from the LLE, only fraction 2 (F2) promoted macrophage reactive oxygen species (ROS) production via a mechanism requiring mitochondrial involvement, whereas the NADPH oxidase system was not involved. Incubation of F2 with PON1 abridged the former's peroxide value and reduced its capacity to oxidize OS markers. The active agent was a triglyceride composed of palmitic, oleic, and linoleic acids, with 0.3% of its linoleic moiety in oxidized form. Incubation of either F2 or an identical synthetic triglyceride with PON1 reduced their ability to oxidize macrophages, without affecting cellular accumulation of triglycerides. We conclude that macrophage ROS production by LLE occurs in the presence of a specific triglyceride and requires mitochondrial involvement. Lipid peroxide in the triglyceride can also facilitate lipid autoxidation. Both atherogenic pathways are suppressed by PON1, which acts as an antiatherogenic element.

Primary prevention of coronary heart disease: integration of new data, evolving views, revised goals, and role of rosuvastatin in management. A comprehensive survey

A recent explosion in the amount of cardiovascular risk and incipient, undetected subclinical cardiovascular pathology has swept across the globe. Nearly 70% of adult Americans are overweight or obese; the prevalence of visceral obesity stands at 53% and continues to rise. At any one time, 55% of the population is on a weight-loss diet, and almost all fail. Fewer than 15% of adults or children exercise sufficiently, and over 60% engage in no vigorous activity. Among adults, 11%-13% have diabetes, 34% have hypertension, 36% have prehypertension, 36% have prediabetes, 12% have both prediabetes and prehypertension, and 15% of the population with either diabetes, hypertension, or dyslipidemia are undiagnosed. About one-third of the adult population, and 80% of the obese, have fatty livers. With 34% of children overweight or obese, prevalence having doubled in just a few years, type 2 diabetes, hypertension, dyslipidemia, and fatty livers in children are at their highest levels ever. Half of adults have at least one cardiovascular risk factor. Not even 1% of the population attains ideal cardiovascular health. Despite falling coronary death rates for decades, coronary heart disease (CHD) death rates in US women 35 to 54 years of age may now be increasing because of the obesity epidemic. Up to 65% of patients do not have their conventional risk biomarkers under control. Only 30% of high risk patients with CHD achieve aggressive low density lipoprotein (LDL) targets. Of those patients with multiple risk factors, fewer than 10% have all of them adequately controlled. Even when patients are titrated to evidence-based targets, about 70% of cardiac events remain unaddressed. Undertreatment is also common. About two-thirds of high risk primary care patients are not taking needed medications for dyslipidemia. Poor patient adherence, typically below 50%, adds further difficulty. Hence, after all such fractional reductions are multiplied, only a modest portion of total cardiovascular risk burden is actually being eliminated, and the full potential of risk reduction remains unrealized. Worldwide the situation is similar, with the prevalence of metabolic syndrome approaching 50%. Primordial prevention, resulting from healthful lifestyle habits that do not permit the appearance of risk factors, is the preferred method to lower cardiovascular risk. Lowering the prevalence of obesity is the most urgent matter, and is pleiotropic since it affects blood pressure, lipid profiles, glucose metabolism, inflammation, and atherothrombotic disease progression. Physical activity also improves several risk factors, with the additional potential to lower heart rate. Given the current obstacles, success of primordial prevention remains uncertain. At the same time, the consequences of delay and inaction will inevitably be disastrous, and the sense of urgency mounts. Since most CHD events arise in a large subpopulation of low- to moderate-risk individuals, identifying a high proportion of those who will go on to develop events with accuracy remains unlikely. Without a refinement in risk prediction, the current model of targeting high-risk individuals for aggressive therapy may not succeed alone, especially given the rising burden of risk. Estimating cardiovascular risk over a period of 10 years, using scoring systems such as Framingham or SCORE, continues to enjoy widespread use and is recommended for all adults. Limitations in the former have been of concern, including the under- or over-estimation of risk in specific populations, a relatively short 10-year risk horizon, focus on myocardial infarction and CHD death, and exclusion of family history. Classification errors may occur in up to 37% of individuals, particularly women and the young. Several different scoring systems are discussed in this review. The use of lifetime risk is an important conceptual advance, since ≥90% of young adults with a low 10-year risk have a lifetime risk of ≥39%; over half of all American adults have a low 10-year risk but a high lifetime risk. At age 50 the absence of traditional risk factors is associated with extremely low lifetime risk and significantly greater longevity. Pathological and epidemiological data confirm that atherosclerosis begins in early childhood, and advances seamlessly and inexorably throughout life. Risk factors in childhood are similar to those in adults, and track between stages of life. When indicated, aggressive treatment should begin at the earliest indication, and be continued for years. For those patients at intermediate risk according to global risk scores, C-reactive protein (CRP), coronary artery calcium (CAC), and carotid intima-media thickness (CIMT) are available for further stratification. Using statins for primary prevention is recommended by guidelines, is prevalent, but remains underprescribed. Statin drugs are unrivaled, evidence-based, major weapons to lower cardiovascular risk. Even when low density lipoprotein cholesterol (LDL-C) targets are attained, over half of patients continue to have disease progression and clinical events. This residual risk is of great concern, and multiple sources of remaining risk exist. Though clinical evidence is incomplete, altering or raising the blood high density lipoprotein cholesterol (HDL-C) level continues to be pursued. Of all agents available, rosuvastatin produces the greatest reduction in LDL-C, LDL-P, and improvement in apoA-I/apoB, together with a favorable safety profile. Several recent proposals and methods to lower cardiovascular risk are reviewed. A combination of approaches, such as the addition of lifetime risk, refinement of risk prediction, guideline compliance, novel treatments, improvement in adherence, and primordial prevention, including environmental and social intervention, will be necessary to lower the present high risk burden.

In vivo D2O labeling to quantify static and dynamic changes in cholesterol and cholesterol esters by high resolution LC/MS

High resolution LC/MS-MS and LC/APPI-MS methods have been established for the quantitation of flux in the turnover of cholesterol and cholesterol ester. Attention was directed toward quantifying the monoisotopic mass (M0) and that of the singly deuterated labeled (M+1) isotope. A good degree of isotopic dynamic range has been achieved by LC/MS-MS ranging from 3-4 orders of magnitude. Correlation between the linearity of GC/MS and LC atmospheric pressure photoionization (APPI)-MS are complimentary (r² = 0.9409). To prove the viability of this particular approach, male C57Bl/6 mice on either a high carbohydrate (HC) or a high fat (HF) diet were treated with ²H₂O for 96 h. Gene expression analysis showed an increase in the activity of stearoyl-CoA desaturase (Scd1) in the HC diet up to 69-fold (P < 0.0008) compared with the HF diet. This result was supported by the quantitative flux measurement of the isotopic incorporation of ²H into the respective cholesterol and cholesterol ester (CE) pools. We concluded that it is possible to readily obtain static and dynamic measurement of cholesterol and CEs in vivo by coupling novel LC/MS methods with stable isotope-based protocols.