Relative importance of different lipid risk factors for the development of myocardial infarction at a very young age (≤ 40 years of age)

HDL-Cholesterol Subfraction Dimensional Distribution Is Associated with Cardiovascular Disease Risk and Is Predicted by Visceral Adiposity and Dietary Lipid Intake in Women

HDL-cholesterol quality, including cholesterol distribution in HDL subfractions, is emerging as a key discriminant in dictating the effects of these lipoproteins on cardiovascular health. This study aims at elucidating the relationship between cholesterol distribution in HDL subfractions and CVD risk factors as well as diet quality and energy density in a population of pre- and postmenopausal women. Seventy-two women aged 52 ± 6 years were characterized metabolically and anthropometrically. Serum HDL-C subfractions were quantified using the Lipoprint HDL System. Cholesterol distribution in large HDL subfractions was lower in overweight individuals and study participants with moderate to high estimated CVD risk, hypertension, or insulin resistance. Cholesterol distribution in large, as opposed to small, HDL subfractions correlated negatively with insulin resistance, circulating triglycerides, and visceral adipose tissue (VAT). VAT was an independent positive and negative predictor of cholesterol distribution in large and small HDL subfractions, respectively. Furthermore, an increase in energy intake could predict a decrease in cholesterol levels in large HDL subfractions while lipid intake positively predicted cholesterol levels in small HDL subfractions. Cholesterol distribution in HDL subfractions may represent an additional player in shaping CVD risk and a novel potential mediator of the effect of diet on cardiovascular health.

Effects of portable pedal machines at work on lipoprotein subfraction profile in sedentary workers - the REMOVE study

BACKGROUND

Sedentary behaviour at work is a major cause of atherosclerosis, particularly in tertiary workers. However, no studies have ever assessed the effect of active workstation on lipoprotein subfraction profile. This study aimed to evaluate the effect of 12-week portable pedal machines (PPMs) on lipoprotein subfraction profile among healthy sedentary workers.

METHODS

Healthy administrative workers were randomized into an intervention group using PPMs for 12 weeks or a control group using normal-desk. Lipoprotein subfractions were assessed using Lipoprint® electrophoresis. Main outcomes were explored using mixed models with sensitivity analyses (four models).

RESULTS

We included 40 participants (43.7 ± 8.6 years old, 100% women, BMI 23.8 ± 3.4 kg/m2; sedentary time at work 7.7 ± 1.8 h/day). Groups did not differ at baseline in any outcomes. 32 participants finished the trial. Changes in lipoprotein subfractions were especially marked for LDL profile. There was an interaction time x group for all parameters related to LDL and their subfractions: total LDL-cholesterol (p = 0.012), LDL particle size (p = 0.027), large LDL subfractions 1 and 2 (p = 0.001), and small dense LDL subfractions 3 to 7 (p = 0.046), using the crude model. The interaction reflects difference in the direction of changes between groups. The LDL particle size significantly increased in the intervention group (from 271.9 ± 2.5 at t0 to 272.8 ± 1.9 Ångström at t1, p = 0.037) while it did not change in the control group (272.5 ± 1.7 at t0 to 271.8 ± 1.5Å at t1, p = 0.52). All interactions were constantly significant whatever the models. Influencing variables were mainly stress at work that was associated with an increase in total LDL-cholesterol (coefficient 3.15, 95CI 0.20 to 6.11 mg/dl, p = 0.038), and BMI that was associated with Large-LDL, Large-HDL, IDL-C and triglycerides.

CONCLUSIONS

Lipoprotein profile was improved after a 12-week PPMs intervention at work in healthy administrative workers. Changes were mainly showed for LDL and LDL subfractions. Lipoprotein profile was worsened by stress at work, BMI and age.

TRIAL REGISTRATION

NCT04153214.

Modifiable and Non-Modifiable Risk Factors for Premature Coronary Heart Disease (PCHD): Systematic Review and Meta-Analysis

AIM

We aimed to compare the prevalence of modifiable and non-modifiable coronary heart disease (CHD) risk factors among those with premature CHD and healthy individuals.

METHODS

PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol is registered in PROSPERO CRD42020173216). The quality of studies was assessed using the National Heart, Lung and Blood Institute tool for cross-sectional, cohort and case-control studies. Meta-analyses were performed using Review Manager 5.3. Effect sizes for categorical and continuous variables, odds ratio (OR) and mean differences (MD)/standardised mean differences (SMD) with 95% confidence intervals (CI) were reported.

RESULTS

A total of n=208 primary studies were included in this review. Individuals presenting with premature CHD (PCHD, age ≤65 years) had higher mean body mass index (MD 0.54 kg/m2, 95% CI 0.24, 0.83), total cholesterol (SMD 0.27, 95% CI 0.17, 0.38), triglycerides (SMD 0.50, 95% CI 0.41, 0.60) and lower high-density lipoprotein cholesterol (SMD 0.79, 95% CI: -0.91, -0.68) compared with healthy individuals. Individuals presenting with PCHD were more likely to be smokers (OR 2.88, 95% CI 2.51, 3.31), consumed excessive alcohol (OR 1.40, 95% CI 1.05, 1.86), had higher mean lipoprotein (a) levels (SMD 0.41, 95% CI 0.28, 0.54), and had a positive family history of CHD (OR 3.65, 95% CI 2.87, 4.66) compared with healthy individuals. Also, they were more likely to be obese (OR 1.59, 95% CI 1.32, 1.91), and to have had dyslipidaemia (OR 2.74, 95% CI 2.18, 3.45), hypertension (OR 2.80, 95% CI 2.28, 3.45), and type 2 diabetes mellitus (OR 2.93, 95% CI 2.50, 3.45) compared with healthy individuals.

CONCLUSION

This meta-analysis confirms current knowledge of risk factors for PCHD, and identifying these early may reduce CHD in young adults.

Cardiovascular and psychosocial risks among patients below age 50 with acute myocardial infarction

BACKGROUND

Despite improvements in the treatment and prevention of cardiovascular disease since the 1960s, the incidence of cardiovascular diseases among young people has remained the same for many years. This study aimed to compare the clinical and psychosocial attributes of young persons affected by myocardial infarction under the age of 50 years compared to middle-aged myocardial infarction patients 51-65 years old.

METHODS

Data from patients with a documented STEMI or NSTEMI elevated acute myocardial infarction in the age groups up to 65 years, were collected from cardiology clinics at three hospitals in southeast Sweden. The Stressheart study comprised a total of 213 acute myocardial infarction patients, of which n = 33 (15.5%) were under 50 years of age and n = 180 (84.5%) were middle-aged, (51-65 years). These acute myocardial infarction patients filled in a questionnaire at discharge from the hospital and further information through documentation of data in their medical records.

RESULTS

Blood pressure was significantly higher in young compared to middle-aged patients. For diastolic blood pressure (p = 0.003), systolic blood pressure (p = 0.028), and mean arterial pressure (p = 0.005). Young AMI patients had a higher (p = 0.030) body mass index (BMI) than the middle-aged. Young AMI patients were reported to be more stressed (p = 0.042), had more frequently experienced a serious life event the previous year (p = 0.029), and felt less energetic (p = 0.044) than middle-aged AMI patients.

CONCLUSIONS

This study revealed that persons under the age of 50 affected by acute myocardial infarction exhibit traditional cardiovascular risk factors like high blood pressure, and higher BMI, and were more exposed to some psychosocial risk factors. The risk profile of young persons under age 50 affected by AMI was in these respects more exaugurated than for middle-aged persons with AMI. This study underlines the importance of the early discovery of those at increased risk and encourages preventative actions to focus on both clinical and psychosocial risk factors.

Risk factors, clinical features, and outcomes of premature acute myocardial infarction

AIMS

To investigate the risk factors, clinical features, and prognostic factors of patients with premature acute myocardial infarction (AMI).

MATERIALS AND METHODS

A retrospective cohort study of patients with AMI included in data from the West China Hospital of Sichuan University from 2011 to 2019 was divided into premature AMI (aged < 55 years in men and < 65 years in women) and non-premature AMI. Patients' demographics, laboratory tests, Electrocardiography (ECG), cardiac ultrasound, and coronary angiography reports were collected. All-cause death after incident premature MI was enumerated as the primary endpoint.

RESULTS

Among all 8,942 AMI cases, 2,513 were premature AMI (79.8% men). Compared to the non-premature AMI group, risk factors such as smoking, dyslipidemia, overweight, obesity, and a family history of coronary heart disease (CHD) were more prevalent in the premature AMI group. The cumulative survival rate of patients in the premature AMI group was significantly better than the non-premature AMI group during a mean follow-up of 4.6 years (HR = 0.27, 95% CI 0.22-0.32, p < 0.001). Low left ventricular ejection fraction (LVEF) (Adjusted HR 3.00, 95% CI 1.85-4.88, P < 0.001), peak N-terminal pro-B-type natriuretic peptide (NT-proBNP) level (Adjusted HR 1.34, 95% CI 1.18-1.52, P < 0.001) and the occurrence of in-hospital major adverse cardiovascular and cerebrovascular events (MACCEs) (Adjusted HR 2.36, 95% CI 1.45-3.85, P = 0.001) were predictors of poor prognosis in premature AMI patients.

CONCLUSION

AMI in young patients is associated with unhealthy lifestyles such as smoking, dyslipidemia, and obesity. Low LVEF, elevated NT-proBNP peak level, and the occurrence of in-hospital MACCEs were predictors of poor prognosis in premature AMI patients.

Lifestyle and metabolic risk factors in patients with early-onset myocardial infarction: a case-control study

AIMS

Family history is a known risk factor for early-onset myocardial infarction (EOMI). However, the role of modifiable lifestyle and metabolic factors in EOMI risk is unclear and may differ from that of older adults.

METHODS

This case-control study included myocardial infarction (MI) patients aged ≤45 years from the Bremen ST-elevation MI Registry and matched controls randomly selected from the general population (German National Cohort) at the same geographical region. Multiple logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the individual and combined associations of lifestyle and metabolic factors with EOMI risk, overall and according to family history for premature MI.

RESULTS

A total of 522 cases and 1191 controls were included. Hypertension, current smoking, elevated waist-to-hip ratio, and diabetes mellitus were strongly associated with the occurrence of EOMI. By contrast, higher frequency of alcohol consumption was associated with decreased EOMI risk. In a combined analysis of the risk factors hypertension, current smoking, body mass index ≥25.0 kg/sqm, and diabetes mellitus, participants having one (OR = 5.4, 95%CI = 2.9-10.1) and two or more risk factors (OR = 42.3, 95%CI = 22.3-80.4) had substantially higher odds of EOMI compared to those with none of these risk factors, regardless of their family history.

CONCLUSION

This study demonstrates a strong association of smoking and metabolic risk factors with the occurrence of EOMI. The data suggest that the risk of EOMI goes beyond family history and underlines the importance of primary prevention efforts to reduce smoking and metabolic syndrome in young persons.

Correlation between atherogenic index of plasma and coronary artery disease in males of different ages: a retrospective study

Background

Atherogenic index of plasma (AIP) as a newly discovered blood lipid parameter was shown to be strongly correlated with coronary artery disease (CAD). However, the blood lipid levels changed with age, so we speculated that the correlation between AIP and CAD was also affected by age.

Methods

A retrospective study was performed on male patients with confirmed or suspected CAD who underwent coronary angiography (CAG) from July 2017 to March 2021. Patients were divided into younger, middle early, middle late, and elderly groups. Patients in each age group were further divided into the non-coronary artery disease (n-CAD) and CAD subgroups according to the CAG diagnostic results. The relationship between blood lipid parameters and CAD was assessed in each age group.

Results

Age-dependent changes of blood lipid levels were mainly found in CAD patients but not in n-CAD patients. With increased age, the levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-C) and AIP were gradually decreased, whereas high-density lipoprotein cholesterol concentration was increased in CAD patients. Multivariate logistic regression analyses showed that AIP was an independent risk factor for CAD in middle early (OR 2.601; CI 1.160–5.832, P = 0.02) and middle late age group (OR 2.707, CI 1.201–6.100, P = 0.016), but not in the younger and elderly groups. LDL-C was an independent risk factor for CAD in all age groups. The areas under curve of AIP for detecting CAD in the middle early and middle late age groups were not higher than that of other blood lipid parameters.

Conclusion

Although this was a single-center study for males only, the correlation between AIP level and CAD risk was age-dependent. AIP was an independent risk factor for CAD in the middle-aged groups. However, the predictive value of AIP for detecting CAD was not better than that of the traditional blood lipid parameters such as LDL-C.

The profile of HDL-C subfractions and their association with cardiovascular risk in the Hungarian general and Roma populations

High-density lipoprotein cholesterol (HDL-C) is not a homogenous lipid fraction, but it can be further divided into subfractions. It is well-known that the Roma population has a high prevalence of reduced HDL-C levels and cardiovascular diseases (CVDs). However, it is unknown how this reduction affects different HDL subfractions, and whether changes in their quantity/representation are associated with an increased cardiovascular risk among them. In the present study, the HDL subfraction profile of the Hungarian general (HG) and the Roma populations were compared, and the subfractions showing a significant difference between the two populations were identified. The association of HDL subfractions with CVD risk estimated by the Framingham risk score (FRS) and the Systematic COronary Risk Evaluation (SCORE) algorithms were also defined. The present study is the first to find a significant association between HDL subfractions and cardiovascular risk estimated by FRS and SCORE. Ten HDL subfractions were investigated on small but carefully selected samples comprising 100 control subjects (with normal lipid profile) and 277 case subjects (with reduced HDL-C levels) from HG and Roma populations of a complex health survey. The level of HDL-1 to 3 subfractions and HDL-L showed a significant inverse association with cardiovascular risk estimated by both SCORE and FRS algorithms, whereas HDL-4 to 6 and HDL-I only for FRS. A higher representation (in %) of HDL-1 to 3 has a significant risk-reducing effect, while HDL-8 to 10 has a risk-increasing effect estimated by FRS. Our results confirmed that reduced levels of HDL-6 and -7 expressed in mmol/L were significantly associated with Roma ethnicity.

Causes, Angiographic Characteristics, and Management of Premature Myocardial Infarction: JACC State-of-the-Art Review

Among patients presenting with acute myocardial infarction (AMI), the proportion of young individuals has increased in recent years. Although coronary atherosclerosis is less extensive in young patients with AMI, with higher prevalence of single-vessel disease and rare left main involvement, the long-term prognosis is not benign. Young patients with AMI with obstructive coronary artery disease have similar risk factors as older patients except for higher prevalence of smoking, lipid disorders, and family history of premature coronary artery disease, and lower prevalence of diabetes mellitus and hypertension. Smoking cessation is by far the most effective secondary preventive measure. Myocardial infarction with nonobstructive coronary arteries is a relatively common clinical entity (10%-20%) among young patients with AMI, with intravascular and cardiac magnetic resonance imaging being key for diagnosis and potentially treatment. Spontaneous coronary artery dissection is a frequent pathogenetic mechanism of AMI among young women, requiring a high degree of suspicion, especially in the peripartum period.

Young adults with nonalcoholic fatty liver disease, defined using the fatty liver index, can be at increased risk of myocardial infarction or stroke

AIM

To investigate the relationship between nonalcoholic fatty liver disease (NAFLD) and cardiovascular events among a nationally representative sample of young adults in Korea.

METHODS AND RESULTS

This population-based cohort study from the Korean National Health Insurance Service included adults who were aged 20 to 39 years when they underwent a health examination between 2009 and 2012. NAFLD was defined as a fatty liver index (FLI) ≥60, and participants were divided into three groups according to FLI (<30, 30-59 and ≥60) to investigate the dose-dependent effect of FLI score. Among 5 324 410 participants, 9.8% had an FLI ≥60. There were 13 051 myocardial infarctions (MIs; 0.39%) and 8573 strokes (0.26%) during a median follow-up of 8.4 years. In multivariable analysis, NAFLD was associated with a higher risk of MI and stroke (hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.61-1.77 and HR  1.73, 95% CI 1.63-1.84, respectively). MI and stroke had dose-dependent relationships with FLI (HR 1.28 in participants with FLI 30-59 and 1.73 in those with FLI ≥60 for MI and HR 1.18 in participants with FLI 30-59 and 1.41 in those with FLI ≥60 for stroke, respectively).

CONCLUSIONS

Nonalcholic fatty liver disease was an independent predictor of MI and stroke in young adults. These results suggest that primary prevention of cardiovascular disease should be emphasized in young adults with NAFLD.

Advanced lipoprotein parameters could better explain atheromatosis in non-diabetic chronic kidney disease patients

Background

Chronic kidney disease (CKD) patients have a high burden of atheromatous cardiovascular disease (ASCVD) not fully explained by traditional lipid parameters. Lipoprotein composition and subclass particle number information could improve ASCVD risk assessment. The objective of this study is to investigate the association of advanced lipoprotein parameters with the risk of atheromatosis in a subpopulation of the NEFRONA study.

Methods

This was a cross-sectional study in 395 non-diabetic individuals (209 CKD and 186 non-diabetic and non-CKD) without statin therapy. Vascular ultrasound examination assessing 10 territories was combined with advanced lipoprotein testing performed by nuclear magnetic resonance spectroscopy. Logistic regression was used to estimate adjusted odds ratios (ORs) per 1 standard deviation increment.

Results

Atheromatosis was more prevalent in CKD patients (33.9% versus 64.6%). After adjusting for age, gender, smoking habit and CKD stage, the amount of triglycerides (TGs) within low-density lipoprotein (LDL) lipoproteins was independently and positively associated with atheromatosis [OR 1.33; 95% confidence interval (CI) 1.03–1.74; P = 0.03]. Similarly, total and medium LDL particles (LDL-Ps) showed a positive association (OR 1.29; 95% CI 1.00–1.68; P = 0.05 and OR 1.34; 95% CI 1.04–1.75; P = 0.03, respectively). TG-loaded medium LDL-Ps were higher in CKD patients compared with controls and showed an adjusted OR of 1.40 (95% CI 1.09–1.82; P = 0.01) in non-diabetic patients (CKD and non-CKD individuals). In contrast, non-diabetic CKD patients showed a similar coefficient but the significance was lost (OR 1.2; 95% CI 0.8–1.7; P = 0.359).

Conclusions

Non-diabetic CKD patients showed a higher amount of TG-loaded medium LDL-Ps compared with controls. These particles were independently associated with atheromatosis in non-diabetic patients.

Pcsk9 is associated with severity of coronary artery lesions in male patients with premature myocardial infarction

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (Pcsk9) correlated with incidence and prognosis of coronary heart disease. However, it is unclear whether Pcsk9 contributed to coronary artery lesion severity in patients with premature myocardial infarction (PMI). The present study investigated associations between Pcsk9 and coronary artery lesion severity in PMI patients who underwent coronary angiography (CAG).

METHODS

This prospective cohort study included young men (age ≤ 45 years, n = 332) with acute MI who underwent CAG between January 2017 and July 2019. Serum Pcsk9 levels and clinical characteristics were evaluated. SYNTAX scores (SYNergy between percutaneous coronary intervention with [paclitaxel-eluting] TAXUS stent and cardiac surgery) were calculated to quantify coronary artery lesions.

RESULTS

Serum Pcsk9 levels were positively associated with SYNTAX scores (r = 0.173, P < 0.05). The diagnostic cutoff value of PSCK9 level was 122.9 ng/mL, yielding an area under the curve (AUC) of 0.63, sensitivity 81%, and specificity 40%. Serum Pcsk9, LDL-C, Apob, NT-proBnp, CK level, and diabetes history were independent predictors of high SYNTAX scores (P < 0.05). After stratifying by serum LDL-C level (cutoff = 2.6 mmol/L), medium-high Pcsk9 levels had increased risk of high SYNTAX scores in patients with high LDL-C (P < 0.05), and higher serum Pcsk9 levels had increased risk of major adverse cardiac events (MACE) after adjusting for confounding factors (P < 0.05).

CONCLUSION

Serum Pcsk9 levels correlates with severity of coronary artery lesion in PMI patients and may serve as a biomarker for severity of coronary artery stenosis in this patient population, which may contribute to risk stratification.

Changes in the profile of circulating HDL subfractions in severe obese adolescents following a weight reduction program

BACKGROUND AND AIMS

Epidemiological studies show that obese adolescents are candidates to suffer cardiovascular pathologies in adulthood. In order to detect subfractions with a diagnostic value for future cardiovascular disorders, we analyzed the complete lipoprotein profile of severely obese adolescents.

METHODS AND RESULTS

Twenty-eight obese adolescents free from comorbidities were admitted into a weight reduction program. Anthropometric parameters were monitored. The circulating lipoproteins and glycemia were measured at the beginning and at the end of the study by conventional blood analysis as well as by using lipoprotein electrophoresis. Twenty-one puberty-matched normal-weight adolescents were recruited as controls. After 4 months, participants improved anthropometric parameters. Blood analysis indicated that circulating lipoproteins were in the healthy range during intervention. Nevertheless, results obtained from lipoprotein electrophoresis showed a significant increase in the large high-density lipoprotein subfraction in the obese population at the end of intervention, but significantly lower than normal-weight counterparts. In addition, intermediate- and low-density lipoprotein subfractions were in the healthy range in controls and in obese adolescents during intervention.

CONCLUSIONS

Altogether, it seems that the obese adolescents with no comorbidities do not develop a clear dyslipidemia. However, low values of large high-density lipoprotein subfractions could be considered as candidate predictors to develop cardiovascular disease in the future. For this reason, diet and exercise are key tools to fight against this pathology.

REGISTRATION NUMBER FOR CLINICAL TRIALS

ISRCTN99414527.

Association of Lipid, Inflammatory, and Metabolic Biomarkers With Age at Onset for Incident Coronary Heart Disease in Women

Importance

Risk profiles for premature coronary heart disease (CHD) are unclear.

Objective

To examine baseline risk profiles for incident CHD in women by age at onset.

Design, Setting, and Participants

A prospective cohort of US female health professionals participating in the Women's Health Study was conducted; median follow-up was 21.4 years. Participants included 28 024 women aged 45 years or older without known cardiovascular disease. Baseline profiles were obtained from April 30, 1993, to January 24, 1996, and analyses were conducted from October 1, 2017, to October 1, 2020.

Exposures

More than 50 clinical, lipid, inflammatory, and metabolic risk factors and biomarkers.

Main Outcomes and Measures

Four age groups were examined (<55, 55 to <65, 65 to <75, and ≥75 years) for CHD onset, and adjusted hazard ratios (aHRs) were calculated using stratified Cox proportional hazard regression models with age as the time scale and adjusting for clinical factors. Women contributed to different age groups over time.

Results

Of the clinical factors in the women, diabetes had the highest aHR for CHD onset at any age, ranging from 10.71 (95% CI, 5.57-20.60) at CHD onset in those younger than 55 years to 3.47 (95% CI, 2.47-4.87) at CHD onset in those 75 years or older. Risks that were also noted for CHD onset in participants younger than 55 years included metabolic syndrome (aHR, 6.09; 95% CI, 3.60-10.29), hypertension (aHR, 4.58; 95% CI, 2.76-7.60), obesity (aHR, 4.33; 95% CI, 2.31-8.11), and smoking (aHR, 3.92; 95% CI, 2.32-6.63). Myocardial infarction in a parent before age 60 years was associated with 1.5- to 2-fold risk of CHD in participants up to age 75 years. From approximately 50 biomarkers, lipoprotein insulin resistance had the highest standardized aHR: 6.40 (95% CI, 3.14-13.06) for CHD onset in women younger than 55 years, attenuating with age. In comparison, weaker but significant associations with CHD in women younger than 55 years were noted (per SD increment) for low-density lipoprotein cholesterol (aHR, 1.38; 95% CI, 1.10-1.74), non-high-density lipoprotein cholesterol (aHR, 1.67; 95% CI, 1.36-2.04), apolipoprotein B (aHR, 1.89; 95% CI, 1.52-2.35), triglycerides (aHR, 2.14; 95% CI, 1.72-2.67), and inflammatory biomarkers (1.2- to 1.8-fold)-all attenuating with age. Some biomarkers had similar CHD age associations (eg, physical inactivity, lipoprotein[a], total high-density lipoprotein particles), while a few had no association with CHD onset at any age. Most risk factors and biomarkers had associations that attenuated with increasing age at onset.

Conclusions and Relevance

In this cohort study, diabetes and insulin resistance, in addition to hypertension, obesity, and smoking, appeared to be the strongest risk factors for premature onset of CHD. Most risk factors had attenuated relative rates at older ages.

Comparison of Clinical Characteristics of Acute Myocardial Infarction Between Young (< 55 Years) and Older (55 to < 70 Years) Patients

Although the incidence of acute myocardial infarction (AMI) has been decreasing in the elderly, it has been increasing in the young, especially in Japan. A social impact of AMI would be greater in the young, because loss of the young directly influences social activities such as business, child-raising, and tax payment. The aim of this study was to identify the specific characteristics of young AMI patients. We retrospectively included 408 consecutive AMI patients < 70 years of age, divided into a young group (< 55 years: n = 136) and an older group (55 to < 70 years: n = 272). The prevalence of overweight was greater in the young group (58.5%) than in the older group (40.7%) (P = 0.001). The frequency of current smokers was higher in the young group (67.6%) than in the older group (44.9%) (P < 0.001). Although the prevalence of hypertension was lower in the young group (66.7%) than in the older group (77.2%) (P = 0.017), that of untreated hypertension was greater in the young group (40.4%) than in the older group (27.2%) (P = 0.007). Furthermore, the prevalence of untreated dyslipidemia was greater in the young group (45.0%) than in the older group (26.6%) (P < 0.001). In conclusion, the young AMI patients had more modifiable risk factors such as obesity, smoking, untreated hypertension, and untreated dyslipidemia than the older patients. There is an unmet medical need for the prevention of AMI in the young generation.

Effect of PCSK9 inhibitor on lipoprotein particles in patients with acute coronary syndromes

Background

To assess the effects of proprotein convertase subtilisin/kexin type 9 inhibitor (evolocumab) on lipoprotein particles subfractions with Nuclear Magnetic Resonance spectroscopy in patients with acute coronary syndromes.

Methods

A total of 99 consecutive patients with ACS were enrolled and assigned to either the experimental group (n = 54) or the control group (n = 45). The combination therapy of PCSK9 inhibitor (Repatha®, 140 mg, q2w) and moderate statin (Rosuvastatin, 10 mg, qn) was administered in the experimental group, with statin monotherapy (Rosuvastatin, 10 mg, qn) in the control group. The therapeutic effects on lipoprotein particle subfractions were assessed with NMR spectroscopy after 8 weeks treatment, and the achievement of LDL-C therapeutic target in both groups were analyzed.

Results

In the experimental group, after 8 weeks of evolocumab combination treatment, the concentrations of blood lipids (TC, LDL-C and its subfractions [LDL-1 to 6], VLDL-C and its subfractions [VLDL-1 to 5], IDL-C, and HDL-C), lipoprotein particles, and their subfractions [VLDL-P, IDL-P, LDL-P, and its subfractions [LDL-P1 to 6], apoB, and LP(a)] demonstrated therapeutic benefits with statistical significance (P < 0.05). The decrease in total LDL-P concentrations was mainly due to a decreased concentration of small-sized LDL particles (LDL-P 5 + 6), which was significantly more prominent than the decrease in medium-sized LDL-P (LDL-P3 + 4) and large-sized LDL-P (LDL-P1 + 2) (P < 0.001). According to lipid control target recommended by the latest China Cholesterol Education Program Expert Consensus in 2019, after 8 weeks treatment, 96.3% patients in the experimental group and 13.3% in the control group had achieved the LDL-C therapeutic target (P < 0.01).

Conclusions

Evolocumab combination treatment for 8 weeks significantly improves the plasma lipid profiles in ACS patients, and significantly decrease the concentration of lipoprotein particles which might contribute to the pathonesis of atherosclerosis.

Association of small, dense LDL-cholesterol concentration and lipoprotein particle characteristics with coronary heart disease: A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to systematically collate and appraise the available evidence regarding the associations between small, dense low-density lipoprotein (sdLDL) and incident coronary heart disease (CHD), focusing on cholesterol concentration (sdLDL-C) and sdLDL particle characteristics (presence, density, and size).

BACKGROUND

Coronary heart disease (CHD) is the leading cause of death worldwide. Small, dense low-density lipoprotein (sdLDL) has been hypothesized to induce atherosclerosis and subsequent coronary heart disease (CHD). However, the etiological relevance of lipoprotein particle size (sdLDL) versus cholesterol content (sdLDL-C) remains unclear.

METHODS

PubMed, MEDLINE, Web of Science, and EMBASE were systematically searched for studies published before February 2020. CHD associations were based on quartile comparisons in eight studies of sdLDL-C and were based on binary categorization in fourteen studies of sdLDL particle size. Reported hazards ratios (HR) and odds ratios (OR) with 95% confidence interval (CI) were standardized and pooled using a random-effects meta-analysis model.

RESULTS

Data were collated from 21 studies with a total of 30,628 subjects and 5,693 incident CHD events. The average age was 67 years, and 53% were men. Higher sdLDL and sdLDL-C levels were both significantly associated with higher risk of CHD. The pooled estimate for the high vs. low categorization of sdLDL was 1.36 (95% CI: 1.21, 1.52) and 1.07 (95% CI: 1.01, 1.12) for comparing the top quartiles versus the bottom of sdLDL-C. Several studies suggested a dose response relationship.

CONCLUSIONS

The findings show a positive association between sdLDL or sdLDL-C levels and CHD, which is supported by an increasing body of genetic evidence in favor of its causality as an etiological risk factor. Thus, the results support sdLDL and sdLDL-C as a risk marker, but further research is required to establish sdLDL or sdLDL-C as a potential therapeutic marker for incident CHD risk reduction.

Effects of Pitavastatin on Lipoprotein Subfractions and Oxidized Low-density Lipoprotein in Patients with Atherosclerosis

It has been demonstrated that pitavastatin can significantly reduce low-density lipoprotein (LDL) cholesterol (LDL-C), but its impact on lipoprotein subfractions and oxidized low-density lipoprotein (oxLDL) has not been determined. The aim of the present study was to investigate the potential effects of pitavastatin on subfractions of LDL and high-density lipoprotein (HDL) as well as oxLDL in untreated patients with coronary atherosclerosis (AS). Thirty-six subjects were enrolled in this study. Of them, 18 patients with AS were administered pitavastatin 2 mg/day for 8 weeks and 18 healthy subjects without therapy served as controls. The plasma lipid profile, lipoprotein subfractions and circulating oxLDL were determined at baseline and 8 weeks respectively. The results showed that pitavastatin treatment indeed not only decreased LDL-C, total cholesterol (TC), triglycerides (TG) and apolipoprotein B (ApoB) levels, and increased HDL cholesterol (HDL-C), but also reduced the cholesterol concentration of all of the LDL subfractions and the percentage of intermediate and small LDL subfractions. Meanwhile, pitavastatin could decrease plasma oxLDL levels. Furthermore, a more close correlation was found between oxLDL and LDL-C as well as LDL subfractions after pitavastatin treatment. We concluded that a moderate dose of pitavastatin therapy not only decreases LDL-C and oxLDL concentrations but also improves LDL subfractions in patients with AS.

Effect of 8-weeks intensive lifestyle intervention on LDL and HDL subfractions

OBJECTIVE

Atherogenic dyslipidemia is a cardinal feature of obesity and the metabolic syndrome, which increases the risk of cardiovascular diseases. Many interventional studies, describing the influence of weight loss on cardiometabolic risks, are bariatric surgery studies. The aim of our study was to analyze the effect of intensive lifestyle changes on LDL- and HDL-cholesterol subfractions and cardiometabolic risk factors in obese subjects.

METHODS

A group of 41 patients with obesity (11M/30F; 44.1±12.4 years; BMI 30.2±6.3kg/m²) participated in an 8-week weight loss interventional program (NCT02325804), consisting of caloric intake reduced by 30% and physical activity (150min/week). Insulin sensitivity was evaluated according to the homeostasis model assessment of insulin resistance (HOMA-IR) and physical fitness was measured using bicycle ergometry. Lipid subfractions were measured using the Lipoprint system (Quantimetrix Corp., CA, USA).

RESULTS

After the intervention, body weight was reduced by 5.4±4.5kg, as well as body fat mass and waist circumference. Physical fitness improved, systolic and diastolic blood pressure as well as heart rate decreased after the intervention. Insulin sensitivity improved after the intervention. Total, LDL, HDL cholesterol, as well as triglycerides decreased after the intervention. Regarding the lipoprotein subfractions, LDL2 and small HDL subfractions decreased, while others have not changed.

CONCLUSION

Eight weeks of diet and physical activity intervention led to weight and fat mass loss and induced improvement of insulin sensitivity, as well as atheroprotective changes of lipid profile. However, the weight loss associated changes in cholesterol subfractions as cardiovascular risk biomarkers deserve further studies.

[Myocardial infarction in young patient: Epidemiological specificities and risk factors]

There is no precise definition of premature coronary artery disease, which is reported most often before the age of 40-50 years. The majority of these patients have at least one of the following three risk factors : male sex, active smoking, and/or premature coronary artery disease. In 2/3 cases, young patients have a ST-elevation myocardial infarction. Cases of coronary dissection are also reported (especially in women in 40aine). There is no specific management. The long-term prognosis is most often pejorative because of a progressive atheroma.

Particularities of Acute Myocardial Infarction in Young Adults

Coronary heart disease occurs more often in patients over the age of 45. However, recent data shows a growing incidence of coronary events in younger patients also. Young patients with acute myocardial infarction (AMI) represent a relatively small proportion of subjects suffering from an acute ischemic event. However, they represent a subset that is distinguished from elderly patients by a different profile of risk factors, often atypical clinical presentation, and different prognosis. The prevalence of risk factors such as smoking, dyslipidemia, and a family history of coronary events is higher in this group of patients compared to the general population with AMI. Because of an important negative impact on the patients’ psychology, impaired working abilities, and a high socioeconomical burden, myocardial infarction in young patients represents an important cardiovascular pathology. This manuscript aims to present the particularities of AMI occuring at a young age, in comparison with the rest of the population with AMI.

Distribution of Paraoxonase-1 (PON-1) and Lipoprotein Phospholipase A2 (Lp-PLA2) across Lipoprotein Subclasses in Subjects with Type 2 Diabetes

Paraoxonase-1 (PON1) and lipoprotein phospholipase A2 (Lp-PLA2) may exert an important protective role by preventing the oxidative transformation of high- and low-density lipoproteins (HDL and LDL, respectively). The activity of both enzymes is influenced by lipidome and proteome of the lipoprotein carriers. T2DM typically presents significant changes in the molecular composition of the lipoprotein subclasses. Thus, it becomes relevant to understand the interaction of PON1 and Lp-PLA2 with the subspecies of HDL, LDL, and other lipoproteins in T2DM. Serum levels of PON1-arylesterase and PON1-lactonase and Lp-PLA2 activities and lipoprotein subclasses were measured in 202 nondiabetic subjects (controls) and 92 T2DM outpatients. Arylesterase, but not lactonase or Lp-PLA2 activities, was inversely associated with TD2M after adjusting for potential confounding factors such as age, sex, smoking, body mass index, hypertension, and lipoprotein subclasses (odds ratio = 3.389, 95% confidence interval 1.069–14.756). Marked difference between controls and T2DM subjects emerged from the analyses of the associations of the three enzyme activities and lipoprotein subclasses. Arylesterase was independently related with large HDL-C and small intermediate-density lipoprotein cholesterol (IDL-C) in controls while, along with lactonase, it was related with small low-density lipoprotein cholesterol LDL-C, all IDL-C subspecies, and very low-density lipoprotein cholesterol (VLDL-C) in T2DM (p < 0.05 for all). Concerning Lp-PLA2, there were significant relationships with small LDL-C, large IDL-C, and VLDL-C only among T2DM subjects. Our study showed that T2DM subjects have lower levels of PON1-arylesterase compared to controls and that T2DM occurrence may coincide with a shift of PON1 and Lp-PLA2 towards the more proatherogenic lipoprotein subclasses. The possibility of a link between the two observed phenomena requires further investigations.

Lipid profile and long-term outcome in premature myocardial infarction

BACKGROUND

Premature myocardial infarction (≤40 years) represents a rare disease with a distinct risk factor profile and a lipid phenotype that is characterized by a predominance of elevated triglyceride-rich lipoproteins. So far high-density and low-density lipoproteins remain the primary targets for risk stratification and treatment evaluation in coronary artery disease, but this strategy might be insensitive in patients with premature myocardial infarction.

AIM

Aim of this study was to investigate the predictive value of different lipid fractions on long-term cardiovascular outcome in patients with premature myocardial infarction.

METHODS

We prospectively enrolled 102 consecutive AMI survivors (≤40 years) in this prospective multicentre study and investigated the influence of the familial combined hypercholesterolaemia phenotype and a corresponding multimarker panel of different lipid fractions on cardiovascular outcome.

RESULTS

Total cholesterol, non-HDL cholesterol, remnant cholesterol and Apo B lipoprotein were significantly higher in patients experiencing MACE as compared to those who did not. The familial combined hypercholesterolaemia phenotype was associated with an unfavourable cardiovascular outcome even after adjustment for potential cofounders (adjusted HR 3.04,95% CI, 1.26-7.34, P = 0.013). Remnant cholesterol revealed the strongest association with MACE (adj.HR 1.94, 95%CI. 1.30-2.99, P = 0.001). Interestingly LDL and HDL revealed no significant impact on cardiovascular outcome in this study cohort.

CONCLUSION

Non-HDL and remnant cholesterol are strongly associated with an unfavourable outcome in patients with premature myocardial infarction and might be the preferred treatment target for lipid-lowering therapy.

Clinical Characteristics and Outcomes in Young Patients With ST-Segment Elevation Myocardial Infarction After Primary Percutaneous Coronary Intervention

BACKGROUND

There are few published studies of ST-segment elevation myocardial infarction (STEMI) in younger individuals. The differences between these "younger" and "older" individuals may not be fully appreciated by clinicians. The aim of this study was to determine the reasons for the earlier presentation and help to identify strategies for prevention of recurrent myocardial infarction (MI) in younger patients.

METHODS

The study population was a cohort of 2,419 consecutive STEMI patients who were treated with primary percutaneous coronary intervention. The median follow-up time of this retrospective study was 2.2 years.

RESULTS

The all-cause mortality rates in patients ≤45 years of age at 30 days, 1 and 2 years were 1.7%, 2.0% and 2.2%, respectively. These rates were lower compared with their older matched counterparts whose all-cause mortality rates were 3.3%, 4.2% and 5.5%, respectively (P = 0.010). The incidence of recurrent MI was 4.0% for all age groups combined, 5.4% for younger patients and 3.8% for older patients. The number of stents showed association with recurrent MI in older patients with a first infarction, whereas only composition factor 1 with significantly higher non-high-density lipoprotein and low-density lipoprotein values was significantly associated with recurrent MI in the younger patients.

CONCLUSIONS

STEMI patients ≤45 years of age more often had lower rates of all-cause mortality, but the risk of recurrent MI was similar to that of older patients. Regardless of triglyceride level, neither non-high-density lipoprotein nor low-density lipoprotein were independent predictors for recurrent MI during the long-term follow-up in younger patients.

SCARB1 Gene Polymorphisms and HDL Subfractions in Coronary Artery Disease

BACKGROUND/AIM

Cardiovascular diseases are a leading cause of mortality and morbidity worldwide. Polymorphisms in the SCARB1 gene are known to be related to plasma lipids.

PATIENTS AND METHODS

Real time-polymerase chain reaction (RT-PCR) was used for identification of SCARB1 polymorphisms and the Lipoprint Quantimetrix System was employed in identification of HDL subfractions.

RESULTS

According to allelic distribution, in both groups SCARB1 AA genotype led to a two-fold decrease in the risk of developing cardiovascular disease (p=0.04), while the GA genotype increased the risk two-fold (p=0.03). According to the HDL subfraction analysis results, the AA genotype had higher levels of big-sized HDL subfraction (p=0.02).

CONCLUSION

The SCARB1AA genotype decreased cardiovascular risk and carrying GA genotype and G allele increased the risk of CAD. AA genotype carriers had higher levels of big-sized HDL subfraction.

Novel findings in relation to multiple anti-atherosclerotic effects of XueZhiKang in humans

Background

Previous studies have clearly demonstrated that XueZhiKang (XZK), an extract of cholestin, can decrease low-density lipoprotein cholesterol (LDL-C) and cardiovascular events. However, the mechanism of the effects of XZK on atherosclerosis (AS) in humans has been reported less frequently. In the present study, we investigated the impact of XZK on lipoprotein subfractions, oxidized LDL (oxLDL), and interleukin-6 (IL-6).

Methods

From October 2015 to July 2016, 40 subjects were enrolled in this study. Of them, 20 subjects with dyslipidemia received XZK 1200 mg/day for 8 weeks (XZK group); 20 additional healthy subjects who did not receive therapy acted as controls. The plasma lipoprotein subfractions, oxLDL, and IL-6 were examined at baseline and again at 8 weeks.

Results

Data showed that XZK could significantly decrease not only plasma LDL-C levels (87.26 ± 24.45 vs. 123.34 ± 23.99, P < 0.001), total cholesterol (4.14 ± 0.87 vs. 5.08 ± 1.03, P < 0.001), triglycerides (0.95 ± 0.38 vs. 1.55 ± 0.61, P < 0.05), and apolipoprotein B (1.70 ± 0.35 vs. 1.81 ± 0.72, P < 0.05), but also oxLDL (36.36 ± 5.31 vs. 49.20 ± 15.01, P < 0.05) and IL-6 (8.50 ± 7.40 vs. 10.40 ± 9.49, P < 0.05). At the same time, XZK reduced the concentration of small LDL-C (1.78 ± 2.17 vs. 6.33 ± 7.78, P < 0.05) and the percentage of the small LDL subfraction (1.09 ± 1.12 vs. 3.07 ± 3.09, P < 0.05).

Conclusions

Treatment with 1200 mg/day XZK for 8 weeks significantly decreased the atherogenic small LDL subfraction and reduced oxidative stress and inflammatory markers, in addition to affecting the lipid profile, suggesting multiple beneficial effects in coronary artery disease.

Atherogenic index of plasma is positively associated with the risk of all-cause death in elderly women : A 10-year follow-up

BACKGROUND

The blood concentrations of total cholesterol and low-density lipoprotein (LDL) do not predict survival in patients older than 60 years. The atherogenic index of plasma (AIP) is a logarithm of the triacylglycerol to high-density lipoprotein (HDL) ratio and a surrogate for the concentration of small dense LDL. It might be a better reflection of the risk of all-cause death in elderly patients.

METHODS

We conducted a prospective observational study of patients with arterial hypertension older than 60 years. The concentrations of total cholesterol, LDL, HDL and triacylglycerol were measured at the time of the recruitment and the patients were observed for 10 years. Cox regression analysis was performed to assess the effects of lipoproteins and AIP on survival.

RESULTS

A total of 500 patients were recruited and 473 of them (226 men, 247 women) either died or successfully completed the 10-year follow-up and were included in the analysis. The AIP was positively associated, while HDL concentration was negatively associated with the risk of all-cause death adjusted for age, smoking habits, statin use, history of diabetes mellitus, myocardial infarction, stroke and peripheral artery occlusive disease (PAOD) in elderly women but not in men. The LDL, total cholesterol, triacylglycerol and non-HDL concentrations were not associated with the risk of death in both sexes.

CONCLUSIONS

The AIP is positively associated with the risk of all-cause death in elderly women with arterial hypertension independent of age, smoking habits, statin therapy and comorbidities.

Potential of lipoproteins as biomarkers in acute myocardial infarction

Acute myocardial infarction (AMI), commonly known as heart attack, is a medical emergency that is potentially fatal if not promptly and properly managed. The early diagnosis of AMI is critically important for the timely institution of pharmacotherapy to prevent myocardial damage and preserve cardiac function. Ischemic insults during AMI cause myocardial tissue damage, releasing the cardiac muscle protein troponin T into the blood stream. Therefore, serum troponin T levels are used as a sensitive and specific indicator of myocardial injury for diagnosing AMI. However, there remains a requirement for developing technologies for more accurate biomarkers or signatures for AMI diagnosis or prognosis. Previous studies have implicated impaired lipid metabolism as a causative factor in AMI development. Lipoproteins are important constituents of lipid metabolism; their levels in the blood stream are a convenient biomarker tool for monitoring lipid metabolism. This review summarizes recent findings (data of studies from 2001 to 2016) regarding the biomarker potentials of various lipoproteins, including low-density lipoprotein, oxidized low-density lipoprotein, high-density lipoprotein, lipoprotein-a, and remnant lipoprotein, for the risk stratification of AMI.

Comprehensive assessment of lipoprotein subfraction profiles according to glucose metabolism status, and association with insulin resistance in subjects with early-stage impaired glucose metabolism

BACKGROUND

Early detection of atherogenic dyslipidemia is crucial. We investigated lipoprotein subfraction parameters according to glucose metabolism status.

METHODS

We recruited 1255 lipid-lowering drug-naïve subjects with normal fasting glucose (NFG; n=200, 15.9%), impaired fasting glucose (IFG; n=443, 35.3%), or type 2 diabetes (T2D; n=612, 48.8%). Lipoprotein subfractions (1-7) were determined by polyacrylamide gel electrophoresis, separating low-density lipoprotein (LDL) into large buoyant LDL (lbLDL, LDL1-2) and small dense LDL (sdLDL, LDL3-7). Lipoprotein subfraction parameters including the sdLDL% (LDL3-7/LDL1-7), the sdLDL/lbLDL ratio (LDL3-7/LDL1-2), and weighted LDL subfraction (LDLSF) scores, were compared between groups. Their associations with insulin resistance, estimated using the homeostasis model assessment of insulin resistance, were examined.

RESULTS

The concentrations of sdLDL particles were significantly higher in subjects with T2D and IFG than in those with NFG (15.78±13.47mg/dl and 14.60±14.33mg/dl, respectively, vs. 12.22±12.31mg/dl). Compared with those with NFG, subjects with IFG or T2D had significantly a higher sdLDL% (15.98±15.26% vs. 19.50±16.21% or 21.46±16.81%, respectively), a higher sdLDL/lbLDL ratio (0.24±0.30 vs. 0.31±0.37 or 0.35±0.39), and a higher LDLSF score (2.08±0.91 vs. 2.30±1.14 or 2.36±1.17). These lipoprotein subfraction parameters had stronger associations with insulin resistance compared to conventional lipid profiles in the IFG and T2D groups.

CONCLUSIONS

Atherogenic dyslipidemia is initiated in an early stage of impaired glucose metabolism, when early intervention might be required.

Lipoprotein Biomarkers and Risk of Cardiovascular Disease: A Laboratory Medicine Best Practices (LMBP) Systematic Review

BACKGROUND

Controversy exists about the incremental utility of nontraditional lipid biomarkers [e.g., apolipoprotein (apo) B, apo A-I, and non-HDL-C] in improving cardiovascular disease (CVD) risk prediction when added to a conventional model of traditional risk factors (e.g., total cholesterol, LDL cholesterol, HDL cholesterol, sex, age, smoking status, and blood pressure). Here we present a systematic review that was conducted to assess the use of nontraditional lipid biomarkers including apo B, apo A-I, apo B/A-I ratio, and non-HDL-C in improving CVD risk prediction after controlling for the traditional risk factors in populations at risk for cardiovascular events.

CONTENT

This systematic review used the Laboratory Medicine Best Practices (LMBP™) A-6 methods. A total of 9 relevant studies published before and including July 2015 comprised the evidence base for this review. Results from this systematic review indicated that after the adjustment for standard nonlipid and lipid CVD risk factors, nontraditional apolipoprotein biomarkers apo B (overall effect = relative risk: 1.31; 95% CI, 1.22-1.40; 4 studies) and apo B/apo A-I ratio (overall effect = relative risk: 1.31; 95% CI, 1.11-1.38; 7 studies) resulted in significant improvement in long-term CVD risk assessment.

SUMMARY

Available evidence showed that nontraditional lipid biomarkers apo B and apo B/apo I ratio can improve the risk prediction for cardiovascular events after controlling for the traditional risk factors for the populations at risk. However, because of insufficient evidence, no conclusions could be made for the effectiveness of apo A-I and non-HDL-C lipid markers to predict the CVD events, indicating a need for more research in this field.

Myocardial Infarction in the "Young": Risk Factors, Presentation, Management and Prognosis

Myocardial infarction (MI) in the "young" is a significant problem, however there is scarcity of data on premature coronary heart disease (CHD) and MI in the "young". This may lead to under-appreciation of important differences that exist between "young" MI patients versus an older cohort. Traditional differences described in the risk factor profile of younger MI compared to older patients include a higher prevalence of smoking, family history of premature CHD and male gender. Recently, other potentially important differences have been described. Most "young" MI patients will present with non-ST elevation MI but the proportion presenting with ST-elevation MI is increasing. Coronary angiography usually reveals less extensive disease in "young" MI patients, which has implications for management. Short-term prognosis of "young" MI patients is better than for older patients, however contemporary data raises concerns regarding longer-term outcomes, particularly in those with reduced left ventricular systolic function. Here we review the differences in rate, risk factor profile, presentation, management and prognosis between "young" and older MI patients.

Soluble galectin-3 is associated with premature myocardial infarction

BACKGROUND

Inflammatory responses are pivotal in the initiation and development of premature atherosclerotic lesions. Galectin-3 represents a valuable biomarker for both progression and destabilization of atherosclerotic lesions. This study aims to assess the involvement of galectin-3 in premature myocardial infarction.

DESIGN

In this multicentre case-control study, we assessed circulating galectin-3 levels in 144 patients comprising 72 consecutive survivors of acute myocardial infarction (≤ 40 years) and 72 hospital controls frequency matched for age, gender and centre.

RESULTS

Patients with acute myocardial infarction showed significantly higher galectin-3 levels as compared to controls in the acute phase of acute myocardial infarction (2552 ± 1992 vs. 1666 ± 829 pg/mL; P < 0·001) as well as in the stable phase 1 year after the index event (3692 ± 1774 vs. 1666 ± 829 pg/mL; P < 0·001). Circulating galectin-3 was significantly and independently associated with premature myocardial infarction in the logistic regression analysis (acute phase: adj. OR per 1-SD change 2·03, 95% CI 1·30-3·19; P = 0·002; stable phase: adj. OR of 6·54 (95% CI 2·56-16·68; P < 0·001). Moreover, we observed a significant correlation between circulating galectin-3 and leucocyte count (r = 0·35, P < 0·001), non-HDL cholesterol (r = 0·23, P = 0·014) and HDL cholesterol (r = -0·29, P = 0·002).

CONCLUSION

We demonstrated that elevated levels of circulating galectin-3 are strongly associated with premature myocardial infarction. Galectin-3 might serve as link between dyslipidaemia as driving force of plaque formation with inflammation as initiator of plaque rupture in patients with premature acute myocardial infarction.

Clinical Profile and Long-Term Prognostic Factors of a Young Chinese Han Population (≤ 40 Years) Having ST-Segment Elevation Myocardial Infarction

BACKGROUND

The proportion of the mainland Chinese population with premature ST-segment elevation myocardial infarction is significantly elevated. Young patients with ST-segment elevation myocardial infarction have a different risk factor profile and clinical outcome compared with elder patients, and may also differ as compared to young patients in Western populations.

METHODS

We analyzed a total of 9462 consecutive ST-segment elevation myocardial infarction patients, and recruited 341 consecutive cases who had survived their first ST-segment elevation myocardial infarction at the age less than 40 years, and followed-up these patients for 5 years.

RESULTS

The most prevalent risk factor in young Chinese ST-segment elevation myocardial infarction patients was smoking (307/341, 90.03%) and male gender (328/341, 96.19%), although young patients had fewer traditional risk factors of acute myocardial infarction than the control group [(1.63 ± 1.03) vs. (2.38 ± 1.15), p < 0.01]. The number of affected vessels in cases was significantly less than in the elder control group (p < 0.01). During the follow-up, blood lipids and blood pressure of most patients reached the target level, while 42.10% of patients reported continuation of smoking. Multivariable data analysis showed that persistence of smoking (OR: 3.784, 95% CI: 1.636-8.751, p < 0.01) was the most significant prognostic factor of cardiac events after adjusting for various confounding factors.

CONCLUSIONS

We demonstrated that cigarette smoking is the most prevalent factor among the avoidable cardiovascular risk factors for young ST-segment elevation myocardial infarctions in China. Accordingly, continued smoking is the most powerful predictor for the recurrence of cardiac events in young Chinese patients with ST-segment elevation myocardial infarction.

KEY WORDS

Premature myocardial infarction; Prognosis; Risk factor.

Effect of short term aerobic exercise on fasting and postprandial lipoprotein subfractions in healthy sedentary men

Background

Our goal was to investigate the effect of short term exercise on fasting and postprandial lipoprotein profile.

Methods

Healthy sedentary men exercised 20 min for four days. The intensity of exercise was modulated to maintain 75–80 % of a calculated HRmax. Before and after the exercise program, fasting and postprandial (4 h after standard meal) concentrations of lipoprotein subfractions were measured by an electrophoresis in polyacrylamide gel and total concentrations of TAG, LDL and HDL by enzymatic colorimetric method. After 2 days of rest, fasting and postprandial concentrations of lipoprotein fractions and subfractions were measured to determine a persistency of a changes in the lipoprotein profile.

Results

4 days of physical exercise led to statistically significant decrease of concentration of triacylglycerol in fasting (76.29 ± 20.07, 53.92 ± 10.90, p < 0.05) and postprandial state (139.06 ± 23.72, 96.55 ± 25.21, p < 0.05) VLDL in fasting (21.88 ± 3.87, 18.00 ± 3.93, p < 0.05) and postprandial state (23.88 ± 3.52, 19.25 ± 3.62, p < 0.05), total cholesterol in fasting (162.26 ± 23.38, 148.91 ± 17.72, p < 0.05) and postprandial state (163.73 ± 23.02, 150.08 ± 18.11, p < 0.05). Atherogenic medium LDL decreased also in fasting (9.89 ± 3.27, 6.22 ± 2.55, p < 0.001) and postprandial state (8.88 ± 6.51, 6.88 ± 5.57, p < 0.001). However decrease of large IDL (25.38 ± 3.54, 23.88 ± 3.91, p < 0.05) and large LDL particles (42.89 ± 11.40, 38.67 ± 9.30) was observed only in postprandial state. Total HDL concentration remained unchanged but we observed statistically significant decrease of small HDL particles in fasting (6.11 ± 2.89, 4.22, p < 0.05) and postprandial state (6.44 ± 3.21, 4.56 ± 1.33, p < 0.05). Concentration of these particles are associated with progression of atherosclerosis. All changes of fasting and postprandial lipoprotein profile disappeared after 2 days of rest.

Conclusion

Just 4 daily settings of 20 min of physical exercise can lead to significant positive changes of fasting and postprandial lipoprotein profile.

Impaired antioxidant HDL function is associated with premature myocardial infarction

BACKGROUND

There is growing evidence that the predictive value of HDL cholesterol levels for cardiovascular risk stratification is limited in patients with coronary artery disease (CAD). HDL function seems to be a more sensitive surrogate of cardiovascular risk estimation than simple serum levels. Therefore, we aimed to assess whether impaired antioxidant HDL function is involved in the development of premature acute myocardial infarction (AMI).

METHODS

In this multicentre case-control study, we compared the antioxidant function of HDL, measured by the HDL inflammatory index (HII), and HDL particle size in 184 patients comprising 92 patients with AMI at a very young age (≤40 years of age) and 92 age- and gender-matched controls.

RESULTS

Antioxidant capacities of HDL were significantly impaired in the acute phase of AMI (HII of 1·50 [IQR 1·10-1·74] vs. 0·56 [IQR 0·41-0·86] in controls, P < 0·001 as well as in the chronic stable phase 1 year after the event (HII of 0·85 [IQR 0·72-1·03] vs. 0·56 [IQR 0·41-0·86], P < 0·001) compared to controls. Moreover, HDL function in the stable phase remained significantly associated with premature MI in adjusted logistic regression analysis with an OR of 2·24 per SD increase of HII (95% CI 1·28-3·91; P = 0·005). Analyses of HDL size revealed a significant correlation between all HDL subfractions and HDL function in controls, whereas this correlation was lost for large and intermediate HDL in AMI patients.

CONCLUSION

Impaired antioxidant function of HDL is independently associated with the development of premature AMI. The maintenance of HDL function might evolve into a significant therapeutic target, especially in patients with premature CAD.

Correlation Between High-Density Lipoprotein and Monocyte Subsets in Patients with Stable Coronary Heart Disease

Background

High-density lipoprotein (HDL) consists of heterogeneous particles with a variety of structures and functions. Its role in atherosclerosis has been gradually recognized. Studies have shown dysfunction of small HDL in patients with coronary artery disease (CAD). Monocytes play an important role in atherosclerosis, which can be divided into 3 subgroups based on the expression of surface markers CD14 and CD16. This study aimed to investigate the association between HDL and monocyte subsets in CAD patients.

Material/Methods

A total of 90 patients with stable CAD were selected in this study. Monocytes were divided into classical monocytes (CM, CD14++CD16−), intermediate monocytes (IM, CD14++CD16+), and non-classical monocytes (NCM, CD14+CD16++). HDL components in serum were determined by high-resolution polyacrylamide gel electrophoresis (detected by Quantimetrix HDL Lipoprint system, referring to HDL subfractions analysis: A new laboratory diagnostic assay for patients with cardiovascular diseases and dyslipoproteinemia).

Results

Serum level of small HDL was positively correlated with circulating proinflammatory NCM (r=0.30; p=0.004), negatively correlated with CM, and not correlated with IM. We also found that disease severity was not associated with diabetes mellitus, glycosylated hemoglobin, hypertension, smoking history, or statin dosage.

Conclusions

Our study confirmed that small HDL level is associated with an increase in NCM and a decrease in CM, suggesting the proinflammatory relationship between small HDL and intrinsic immune function during the progression of stable CAD.

Effects of Hedan Tablet () on lipid profile, proprotein convertase subtilisin/kexin type 9 and high-density lipoprotein subfractions in patients with hyperlipidemia: A primary study

OBJECTIVE

To investigate the effects of Hedan Tablet () on serum lipid profile, proprotein convertase subtilisin/kexin type 9 (PSCK9) and high-density lipoprotein (HDL) subfractions in patients with hyperlipidemia.

METHODS

Thirty-seven patients with hyperlipidemia were randomized to treatment with Hedan Tablet 4.38 g/day as Hedan group (18 cases) or placebo (19 cases) as control group for 8 weeks. The lipid profile, PCSK9 and HDL subfractions were determined at day 0 and week 8 in both groups respectively.

RESULTS

Hedan treatment for 8 weeks mildly decreased serum low-density lipoprotein cholesterol (LDL-C) levels, while no changes were found in total cholesterol (TC), triglycerides (TG) and PCSK9 concentrations. Furthermore, Hedan treatment increased the concentration of large high-density lipoprotein cholesterol (HDL-C) and the percentage of large HDL subfraction, while decreased the concentration of small HDL-C and the percentage of small HDL subfraction without changing serum HDL-C levels in patients with hyperlipidemia.

CONCLUSION

Hedan treatment of 4.38 g per day for 8 weeks could confer a favorable effects on serum LDL-C concentration as well as HDL subfractions.

Relationship between plasma phospholipase A2 concentrations and lipoprotein subfractions in patients with stable coronary artery disease

BACKGROUND

Both increased lipoprotein-associated phospholipase A2 (Lp-PLA2) concentrations and atherogenic lipoprotein subfractions have been shown to reflect unfavourable cardiovascular risk. However, the correlation between Lp-PLA2 and lipoprotein subfractions in patients with coronary artery disease (CAD) has not been assessed yet.

METHODS

A total of 324 consecutive subjects who were not treated with lipid-lowering drugs were enrolled (angiographically proven CAD: n = 253; non-CAD: n = 71). Plasma Lp-PLA2 concentrations were measured using ELISA. The low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subfractions were determined by Lipoprint System.

RESULTS

Plasma Lp-PLA2 concentrations were higher in patients with CAD compared with those without CAD (153.61 ± 78.73 vs. 131.41 ± 65.49 ng/ml, p = 0.028). The univariable correlation analysis revealed that Lp-PLA2 concentrations were positively correlated with the cholesterol concentrations of each LDL subfractions and the intermediate as well as small HDL subfractions, while negatively linked with the LDL particle size and large HDL-cholesterol (HDL-C) concentrations in CAD group. However, no similar results were observed in the non-CAD group. Furthermore, multivariable regression analysis was performed in patients with CAD and showed that plasma Lp-PLA2 concentrations were independently correlated with the cholesterol concentrations of each LDL subfractions [large LDL-cholesterol (LDL-C): β = 0.263, p < 0.001; intermediate LDL-C: β = 0.327, p < 0.001; small LDL-C: β = 0.135, p = 0.033] and small HDL-C (β = 0.133, p = 0.034).

CONCLUSION

Lp-PLA2 concentrations were positively associated with all LDL subfractions and small HDL subfraction, suggesting an interaction between Lp-PLA2 and lipoprotein subfraction phenotypes in the status of CAD.

Association of small dense LDL serum levels and circulating monocyte subsets in stable coronary artery disease

Objective

Atherosclerosis is considered to be an inflammatory disease in which monocytes and monocyte-derived macrophages play a key role. Circulating monocytes can be divided into three distinct subtypes, namely in classical monocytes (CM; CD14++CD16-), intermediate monocytes (IM; CD14++CD16+) and non-classical monocytes (NCM; CD14+CD16++). Low density lipoprotein particles are heterogeneous in size and density, with small, dense LDL (sdLDL) crucially implicated in atherogenesis. The aim of this study was to examine whether monocyte subsets are associated with sdLDL serum levels.

Methods

We included 90 patients with angiographically documented stable coronary artery disease and determined monocyte subtypes by flow cytometry. sdLDL was measured by an electrophoresis method on polyacrylamide gel.

Results

Patients with sdLDL levels in the highest tertile (sdLDL≥4mg/dL;T3) showed the highest levels of pro-inflammatory NCM (15.2±7% vs. 11.4±6% and 10.9±4%, respectively; p<0.01) when compared with patients in the middle (sdLDL=2-3mg/dL;T2) and lowest tertile (sdLDL=0-1mg/dL;T1). Furthermore, patients in the highest sdLDL tertile showed lower CM levels than patients in the middle and lowest tertile (79.2±8% vs. 83.9±7% and 82.7±5%; p<0.01 for T3 vs. T2+T1). Levels of IM were not related to sdLDL levels (5.6±4% vs. 4.6±3% vs. 6.4±3% for T3, T2 and T1, respectively). In contrast to monocyte subset distribution, levels of circulating pro- and anti-inflammatory markers were not associated with sdLDL levels.

Conclusion

The atherogenic lipoprotein fraction sdLDL is associated with an increase of NCM and a decrease of CM. This could be a new link between lipid metabolism dysregulation, innate immunity and atherosclerosis.

Non-high-density cholesterol level as a predictor of maximum carotid intima-media thickness in Japanese subjects with type 2 diabetes: a comparison with low-density lipoprotein level

Aim

To determine whether non-high-density lipoprotein cholesterol (non-HDL-C) level, in comparison with low-density lipoprotein cholesterol (LDL-C) level, is useful for predicting the values of various surrogate atherosclerosis markers in Japanese subjects with type 2 diabetes (T2DM).

Methods

Data were retrieved from medical records of 265 subjects with T2DM who underwent laboratory tests to evaluate for atherosclerosis by using the following parameters: brachial-ankle pulse wave velocity, mean and maximum carotid intima-media thickness (mean CIMT and max-CIMT), and ankle-brachial index, with simultaneous fasting blood sampling for routine lipid parameters.

Results

In a multiple stepwise regression analysis, non-HDL-C level, but not LDL-C level, positively correlated with max-CIMT (β coefficient = 0.14, F = 6.84). Stepwise logistic regression analysis revealed that a 0.26 mmol/L (10 mg/dL) increase in non-HDL-C level, but not LDL-C level, was significantly associated with high risk of max-CIMT (≥1.1 mm; odds ratio, 1.096; 95 % confidence interval, 1.003-1.202; p = 0.046). However, in a receiver operating characteristic curve (ROC) analysis, the addition of non-HDL-C level to the three significant independent variables obtained from the stepwise analyses did not significantly increased the area under the ROC curve (from 0.7789 to 0.7864, p = 0.4343).

Conclusions

Non-HDL-C levels may be non-inferior to LDL-C level for the prediction of high-risk max-CIMT in Japanese subjects with T2DM.

Lipoprotein subfractions partly mediate the association between serum uric acid and coronary artery disease

BACKGROUND

Serum uric acid (SUA) has been established to be highly associated with coronary artery disease (CAD) susceptibility and lipid metabolism, but the underlying mechanisms are unclear. Recently, lipoprotein subfractions have been proposed to be more valuable in CAD risk evaluation. Hence, we sought to investigate whether the relationship between SUA and CAD is partly mediated by lipoprotein subfractions.

METHODS

A total of 401 consecutive subjects undergoing coronary angiography were enrolled. The baseline clinical data including the SUA level and lipid profiles were collected. The lipoprotein subfractions were determined using the Lipoprint system.

RESULTS

In the overall population, the upper SUA quintiles had significantly higher atherogenic lipid parameters and unbalanced lipoprotein subfractions especially higher small dense low-density lipoprotein-cholesterol (sdLDL-C) and lower large high-density lipoprotein-cholesterol (HDL-C) (p<0.05). The levels of SUA and lipoprotein subfractions were dramatically different between male and female. After adjusting for traditional risk factors including gender, multivariate linear regression analysis suggested that SUA was positively associated with sdLDL-C (β=0.113, p=0.013) but negatively related to large HDL-C level (β=-0.152, p=0.002). Given the significant association of the SUA level with lipoprotein subfractions and incident CAD (adjusted OR=1.312, 95% CI 1.069-1.609, p=0.009), we performed the mediation analyses and found that 8.7-10.5% of the effect of SUA on CAD susceptibility was mediated by the increased sdLDL-C or decreased large HDL-C level (p<0.05).

CONCLUSIONS

The SUA level was proved to be associated with lipoprotein subfractions including sdLDL-C (positive) and large HDL-C (negative), which partly mediated the association between SUA and CAD susceptibility.

High-density lipoprotein subfractions in relation with the severity of coronary artery disease: A Gensini score assessment

BACKGROUND

The exact role of different high-density lipoprotein (HDL) subfractions in the pathogenesis of coronary artery disease (CAD) has not yet been fully explored. The aim of the present study was to examine the relationship between HDL subfractions and the severity of CAD in patients without statin therapy.

METHODS

A total of 382 consecutive patients (mean: 55.36 ± 11.30 years of age) who underwent coronary angiography from angina-like chest pain were investigated. Patients were classified into 2 groups according to the angiographic results: a CAD group (n = 283) and a control group (n = 99). The distribution of HDL subfractions was analyzed using a Quantimetrix Lipoprint HDL system. CAD severity was measured by Gensini score (GS).

RESULTS

Compared with the control group, HDL-cholesterol (HDL-C), large HDL-C level, and the large HDL subfraction percentages in the CAD group were significantly lower (P = .002, P < .001, P < .001, respectively). Meanwhile, a small HDL-C level and the percentage of small HDL subfraction were significantly higher (P = .003, P < .001, respectively). Correlation analysis showed that the percentage of a large HDL subfraction was negatively correlated with GS (β = -0.191, P = .005), whereas the percentage of a small HDL subfraction positively correlated with GS (β = 0.145, P = .023) in patients with CAD.

CONCLUSIONS

Small HDL subfraction was associated with the presence of CAD, whereas the percentage of large HDL and small HDL subfraction was negatively and positively associated with the severity of CAD, respectively.

Small high-density lipoprotein is associated with monocyte subsets in stable coronary artery disease

Objective: High-density lipoprotein (HDL) particles are heterogeneous in structure and function and the role of HDL subfractions in atherogenesis is not well understood. It has been suggested that small HDL may be dysfunctional in patients with coronary artery disease (CAD). Monocytes are considered to play a key role in atherosclerotic diseases. Circulating monocytes can be divided into three subtypes according to their surface expression of CD14 and CD16. Our aim was to examine whether monocyte subsets are associated with HDL subfractions in patients with atherosclerosis. Methods: We included 90 patients with angiographically stable CAD. Monocyte subsets were defined as classical monocytes (CD14++CD16-; CM), intermediate monocytes (CD14++CD16+; IM) and non-classical monocytes (CD14+CD16++; NCM). HDL subfractions were measured by electrophoresis on polyacrylamide gel. Results: Serum levels of small HDL correlated with circulating pro-inflammatory NCM and showed an inverse relationship to circulating CM independently from other lipid parameters, risk factors, inflammatory parameters or statin treatment regime, respectively. IM were not associated with small HDL. In particular, patients with small HDL levels in the highest tertile showed dramatically increased levels of NCM (14.7 ± 7% vs. 10.7 ± 5% and 10.8 ± 5%; p = 0.006) and a decreased proportion of CM (79.3 ± 7% vs. 83.7 ± 6% and 83.9 ± 6%; p = 0.004) compared to patients in the two lower tertiles. In contrast, intermediate HDL, large HDL and total HDL were not associated with monocyte subset distribution. Conclusion: Small HDL levels are associated with pro-inflammatory NCM and inversely correlated with CM. This may suggest that small HDL could have dysfunctional anti-inflammatory properties in patients with established CAD.

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Small HDL levels are associated with non-classical monocytes in stable CAD.

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Classical monocytes are inversely associated with small HDL levels.

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Associations are independent of other lipid parameters, risk factors, inflammatory parameters or statin treatment regime.

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Inflammatory markers do not vary according to small HDL levels.

Atherogenic subfractions of lipoproteins in the treatment of metabolic syndrome by physical activity and diet - the RESOLVE trial

Background

We aimed to comprehensively evaluate lipoprotein profile including lipid particle size following a lifestyle intervention in metabolic syndrome (MetS) volunteers and to assess the associations between lipoprotein subfractions and carotid-intima-media-thickness (CIMT) – a surrogate indicator of atherogenesis.

Methods

100 participants (50–70 years) from the RESOLVE trial, underwent a one-year follow-up beginning with a three-week residential program combining high exercise volume (15-20 h/week), restrictive diet (-500 kcal/day), and education. For baseline references, 40 aged-matched healthy controls were recruited. Independent associations between subfractions of lipoproteins and CIMT were evaluated using a generalized estimating equations model accounting for variation in correlations between repeated measures. The lipoprotein subfractions profile was assessed using Lipoprint® electrophoresis allowing to separate: the very low-density lipoprotein (VLDL) fraction, then the intermediate-density lipoprotein (IDL) C, B and A, the low-density lipoprotein (LDL) with subfractions 1 and 2 as large LDL and subfractions 3 to 7 as small dense LDL (sdLDL), and the high density lipoprotein (HDL) subfractions categorized into large, intermediate, and small HDL. Apolipoproteins A1 and B were also measured.

Results

78 participants completed the program. At baseline, apolipoproteins B/A1, VLDL, sdLDL and small HDL were higher in MetS than in healthy controls; IDL, LDL size, large and intermediate HDL were lower. Despite time-related regains during the follow-up, lipoprotein subfractions traditionally involved in cardiovascular risk, such as sdLDL, improved immediately after the residential program with values closest to those of healthy controls. CIMT improved throughout the lifestyle intervention. Using a generalized estimating equations model, none of the subfractions of lipoproteins nor apolipoproteins were linked to CIMT.

Conclusions

Lipoprotein subfractions traditionally involved in CVR, decreased after the 3-week residential program. During a 12 month follow-up, the time-related regains remained closer to the values of healthy controls than they were at baseline. CIMT improved throughout the lifestyle intervention. However, we failed to demonstrate a link between some lipoprotein subfractions and the atherogenicity directly measured from the wall thickness of arteries (CIMT). Further investigations are required to explore the atherogenicity of lipoprotein subfractions.

Trial registration

NCT00917917

Dietary grape powder increases IL-1β and IL-6 production by lipopolysaccharide-activated monocytes and reduces plasma concentrations of large LDL and large LDL-cholesterol particles in obese humans

Obese individuals are at an increased risk of developing CVD, hypertension, type 2 diabetes, and bacterial and viral infections when compared with the normal-weight population. In a 9-week randomised, double-blind, cross-over study, twenty-four obese subjects aged between 20 and 60 years and with a BMI between 30 and 45 kg/m2were fed grape or placebo powder for 3-week intervals to determine the effects of dietary grapes on blood lipid profiles, plasma inflammatory marker concentrations and immune cell function. Blood samples were collected on days 1 and 8 for obtaining baseline information and at weeks 3, 4, 8 and 9. Comprehensive chemistry panels, lipid profile analyses by NMR, measurement of plasma inflammatory marker concentrations, and analyses of cytokine production by activated T lymphocytes and monocytes were performed for each blood draw. Dietary grape powder reduced the plasma concentrations of large LDL-cholesterol and large LDL particles compared with the placebo powder (P< 0·05). The concentrations of interferon-γ, TNF-α, IL-4 and IL-10 were measured in supernatants from peripheral blood mononuclear cells (PBMC) activated with anti-CD3/CD28 antibodies and those of TNF-α, IL-1β, IL-6 and IL-8 were measured in supernatants from PBMC activated with lipopolysaccharide (LPS). No difference in the production of T-cell cytokines was observed between the two intervention groups. The production of IL-1β and IL-6 was increased in supernatants from LPS-activated PBMC in the grape powder group compared with the placebo powder group (P< 0·05). These data suggest that dietary grapes may decrease atherogenic lipid fractions in obese individuals and increase the sensitivity of monocytes in a population at a greater risk of developing infections.