Atherogenic dyslipidemia and oxidative stress: a new look

Although results from in vitro studies and clinical trials demonstrate strong associations between oxidative stress and cardiovascular risk, to date still no convincing data are available to suggest that treatment with antioxidants might reduce vascular events. Oxidative modifications of low-density lipoproteins (LDL) represent an early stage of atherosclerosis, and small, dense LDL are more susceptible to oxidation than larger, more buoyant particles. Oxidized LDL are independent predictors of subclinical and clinical atherosclerosis. Recent studies suggested that novel therapeutic strategies may take into account the removal of such particles from circulation. Future research is required …

Effects on lipoprotein subclasses of combined expression of human hepatic lipase and human apoB in transgenic rabbits

Objective— The effects of combined expression of human hepatic lipase (HL) and human apolipoprotein B (apoB) on low-density lipoprotein (LDL) subclasses were examined in rabbits, a species naturally deficient in HL activity. Methods and Results— In apoB-transgenic rabbit plasma, >80% of the protein was found in the 1.006- to 1.050-g/mL fraction. Gradient gel electrophoresis (GGE) of this fraction revealed two distinct species, designated large and small LDL. A denser fraction (d=1.050 to 1.063 g/mL) contained small LDL as well as another discrete LDL subspecies, designated very small LDL. Expression of HL resulted in reductions in protein concentrations in the 1.006- to 1.050-g/mL densi…

Post-prandial alterations in LDL size and subclasses in patients with growth hormone deficiency

Abstract Objective Several studies have suggested that lipoproteins generated during the post-prandial phase are highly atherogenic, with modifications in low-density lipoproteins (LDL) size and density. In the present study we assessed post-prandial variations in LDL size and subclasses in patients with growth hormone deficiency (GHD). Design We studied in 12 hypopituitary patients with GHD and 10 healthy control subjects matched for gender, age and body mass index (BMI) post-prandial variations after a standardized meal consisting of 35% fat, 45% carbohydrate and 20% of protein (Clinutren Mix ® , Nestle) and containing calories corresponding to 1/3 of estimated basal metabolic rate. Blood…

The clinical relevance of low-density-lipoproteins size modulation by statins.

The predominance of small, dense low density lipoproteins (LDL) has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III; in fact, LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart disease. Several studies have also shown that the therapeutical modulation of LDL size is of great benefit in reducing the risk of cardiovascular events. Hypolipidemic treatment is able to alter LDL subclass distribution and statins are currently the most widely used lipid-lowering agents. Statins are potent inhibitors of hydroxy-methyl-glutaryl-coenzyme A reductase, the rate-limiting en…

Atherogenic forms of dyslipidaemia in women with polycystic ovary syndrome.

OBJECTIVE: Dyslipidaemia is very common in patients with polycystic ovary syndrome (PCOS) but, beyond plasma lipids, atherogenic lipoprotein (Lp) and apolipoprotein (apo) alterations are still ill defined. DESIGN: We measured concentrations of apoB, Lp(a) and small, dense low-density lipoprotein (LDL) in 42 patients with PCOS [age: 28 +/- 7 years, body mass index (BMI): 27 +/- 5 kg/m(2)] vs. 37 age- and BMI-matched healthy controls. METHODS: Elevated Lp(a) levels considered were those > 30 mg/dl while elevated apoB concentrations were those > 100 g/l. RESULTS: Polycystic ovary syndrome showed increased triglycerides levels (p = 0.0011) and lower high-density lipoprotein (HDL)-cholesterol co…

A case of bowel schistosomiasis not adhering to endoscopic findings

Schistosomiasis is a chronic worm infection caused by a species of trematodes, the Schistosomes. We may distinguish a urinary form from Schistosomes haematobium and an intestinal-hepatosplenic form mainly from Schistosomes mansoni characterized by nausea, meteorism, abdominal pain, bloody diarrhea, rectal tenesmus, and hepatosplenomegaly. These infections represent a major health issue in Africa, Asia, and South America, but recently S mansoni has increased its prevalence in other continents, such as Europe countries and North America, due to international travelers and immigrants, with several diagnostic and prevention problems. We report a case of a 24-year-old patient without HIV infecti…

An Update on the Role of the Quality of LDL in Cardiovascular Risk:The Contribution of the Universities of Palermo and Zurich

Low density lipoproteins (LDL) size seems to be an important predictor of cardiovascular events and progression of coronary artery disease and the predominance of small dense LDL have been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. We recently showed increased LDL size or higher levels of small, dense LDL in different categories of patients at higher cardiovascular risk, such as those with coronary (including acute myocardial infarction) and non-coronary (including carotid disease, abdominal aortic aneurysm and peripheral arterial disease) forms of atherosclerosis or metabolic diseases (including type-II diabet…

Should we measure routinely the LDL peak particle size?

Low density lipoproteins (LDL) do not show in humans a normal distribution and comprise two different main fractions: large, buoyant (phenotype pattern A) and small, dense (phenotype pattern B) particles, that differ not only in size and density but also in physicochemical composition, metabolic behaviour and atherogenicity. The prevalence of small, dense LDL changes with age (30-35% in adult men, 5-10% in men <20 years and in pre-menopausal women, 15-25% in postmenopausal women) and is genetically influenced, with a heritability ranging from 35% to 45%. Small, dense LDL correlate negatively with plasma HDL levels and positively with plasma triglyceride levels and are associated with the me…

Is diabetes the cost to pay for a greater cardiovascular prevention?

The recent JUPITER (Justification for the Use of statins in Primary prevention: an Intervention Trial Evaluating Rosuvastatin) trial is another study providing evidence about the effectiveness of statin therapy in reducing cardiovascular risk. Yet, in this study significantly higher glycated hemoglobin levels and incidence rates of diabetes were observed in persons treated with rosuvastatin than the placebo group. It should be noted that adverse effects on glucose metabolism have already been reported, albeit rarely, in previous trials with statins. Although the exact mechanisms involved are unknown, it seems that statins may deteriorate glycemic control by decreasing different metabolites,…

The therapeutic modulation of atherogenic dyslipidemia and inflammatory markers in the metabolic syndrome: what is the clinical relevance?

The metabolic syndrome consists of a constellation of clinical and biochemical risk factors that cluster together and heighten the risk for atherogenesis, cardiovascular diseases, and diabetes. Established risk cardiovascular factors like hypertension, atherogenic dyslipidaemia, and glucose intolerance occur in the setting of insulin resistance and central adiposity, with genetic and environmental influences modulating the ultimate risk. Chronic insults to the endothelium take its toll in the form of silent as well as clinically evident cardiovascular events. The cellular and vascular accompaniments have shed some light into the underlying pathophysiology. Heightened, low-grade inflammatory…

LDL size and subclasses in patients with abdominal aortic aneurysm

Abstract Since the type of dyslipidemia in patients with abdominal aortic aneurysm (AAA) is still insufficiently defined, we measured plasma lipids and analyzed LDL size and subclasses by gradient gel electrophoresis in 30 male patients (69±6 years, BMI: 27±3) with newly diagnosed AAA and in 26 age- and BMI-matched male healthy controls. Patients with AAA had lower HDL-cholesterol ( p p =.0002) and smaller LDL size ( p p =.0210) in relation to controls. Multivariate analysis also showed that small LDL size was independently associated with the presence of AAA ( p =.0350). Increased levels of small, dense LDL may therefore represent a common feature in patients with AAA.

Quantitative and qualitative effects of rosuvastatin on LDL-cholesterol: what is the clinical significance ?

Summary Background:  Statins have emerged as the global leader in pharmacologic therapy for dyslipidaemia, and rosuvastatin has demonstrated clinical efficacy as well as safety in several clinical trials and postmarketing analyses. Aim:  The present article reviewed the effects of rosuvastatin on the quantity and the quality of low-density lipoproteins (LDL). Methods:  We searched for and reviewed all the available evidence in a systematic way. A literature search (by Medline and Scopus) was performed using the following headings: ‘LDL-cholesterol’, ‘LDL size’, ‘LDL subclasses’, ‘small dense LDL’, ‘apolipoprotein B, apo B’ and ‘rosuvastatin’ up to 11 November 2008. The authors also manually…

Small, dense low-density lipoproteins (LDL) are predictors of cardio- and cerebro-vascular events in subjects with the metabolic syndrome

Summary Objective  Small, dense low-density lipoproteins (LDL) are a feature of the metabolic syndrome (MS) but their predictive role still remains to be established. We performed a 2-year follow-up study in 124 subjects with MS (63 ± 6 years), as defined by the American Heart Association/National Heart, Lung and Blood Institute guidelines, to assess clinical and biochemical predictors of cerebro- and cardio-vascular events. Methods and results  Beyond traditional cardiovascular risk factors, we measured LDL size and subclasses by gradient gel electrophoresis. Clinical events were registered in the 25% of subjects. At univariate analysis subjects with events had increased prevalence of elev…

Low-density-lipoproteins size and cardiovascular prevention

Low-density lipoprotein (LDL) size appears to be an important predictor of cardiovascular events and progression of coronary artery disease, and the predominance of small, dense LDL has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. Yet, other authors have suggested that LDL subclass measurement does not add independent information to that conferred generically by LDL concentration and other standard risk factors. Therefore, the debate continues as to whether to measure LDL particle size for cardiovascular prevention and, if so, in which categories of patients. Since the therapeutic modulation of distinct LDL …

Milder forms of atherogenic dyslipidemia in ovulatory versus anovulatory polycystic ovary syndrome phenotype

BACKGROUND: Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) but its prevalence in different PCOS phenotypes is still largely unknown. METHODS: We measured plasma lipids and lipoproteins in 35 anovulatory PCOS (age: 25 ± 6 years, BMI: 28 ± 6 kg/m2), 15 ovulatory PCOS (age: 30 ± 6 years, BMI: 25 ± 3 kg/m2) and 27 healthy women (controls) age- and BMI-matched with ovulatory PCOS. PCOS was diagnosed by the presence of clinical or biologic hyperandrogenism associated with chronic anovulation and/or polycystic ovaries at ultrasound. In women with normal menses chronic anovulation was indicated by low serum progesterone levels (&lt;9.54 nmol/l) during midluteal phase (days 21…

&amp;#x201C;European Panel on Low Density Lipoprotein (LDL) Subclasses&amp;#x201D;: A Statement on the Pathophysiology, Atherogenicity and Clinical Significance of LDL Subclasses

Aim of the present Consensus Statement is to provide a comprehensive and up to-date document on the pathophysiology, atherogenicity and clinical significance of low density lipoproteins (LDL) subclasses. We sub-divided our Statement in 2 sections: section I discusses the pathophysiology, atherogenicity and measurement issues, while section II is focused on the effects of drugs and lifestlyle modifications. Suggestions for future research in the field are highlighted at the end of section II. Each section includes Conclusions.

Comparative effects of rosiglitazone and pioglitazone on fasting and postprandial low-density lipoprotein size and subclasses in patients with Type 2 diabetes

To assess the effects of pioglitazone and rosiglitazone on fasting and postprandial low-density lipoprotein (LDL) size and subclasses in patients with Type 2 diabetes.Nine Type 2 diabetic patients (age 61 +/- 10 years, body mass index 30 +/- 5 kg/m(2), glycosylated hemoglobin [HbA1c] 7.5 +/- 0.5%) were randomized in a crossover trial to rosiglitazone 4 mg b.i.d. or pioglitazone 45 mg/day for 12 weeks with an 8-week wash-out period. LDL size and subclasses were determined by non-denaturing polyacrylamide gradient gel electrophoresis. A standardized breakfast was served and variables were assessed after 3 and 6 h.HbA1c, insulin sensitivity (as assessed by the homeostasis model assessment) and…

Ethnic differences in serum lipoproteins and their determinants in South African women.

The objective of the study was to characterize ethnic differences in lipid levels and low-density lipoprotein (LDL) particle size and subclasses in black and white South African women and to explore the associations with insulin sensitivity (S(I)), body composition, and lifestyle factors. Fasting serum lipids and LDL size and subclasses, body composition (dual-energy x-ray absorptiometry), and S(I) (frequently sampled intravenous glucose tolerance test) were measured in normal-weight (body mass index25 kg/m(2)) black (n = 15) and white (n = 15), and obese (body mass index30 kg/m(2)) black (n = 13) and white (n = 13) women. Normal-weight and obese black women had lower triglycerides (0.59 +/…

The clinical significance of the size of low-density-lipoproteins and the modulation of subclasses by fibrates

Beyond total low-density-lipoproteins (LDL) levels, increasing evidence suggests that the 'quality' of LDL exerts a great influence on the cardiovascular risk. Several studies have also shown that the therapeutic modulation of LDL size is of benefit in reducing the risk of cardiovascular events. Hypolipidaemic treatment is able to alter LDL subclass distribution but strong variations have been noticed among different agents. Fibrates have a major impact on triglyceride metabolism and in modulating LDL size and subclasses, but variations exist among the different molecules.A literature search (by Medline and Scopus) was performed using the following headings: 'small dense LDL', 'LDL size', '…

Ethnic Differences in Serum Lipids and the Association with Insulin Sensitivity, Body Composition and Lifestyle Factors in South African Women

Therapy with non-invasive ventilation in patients with obstructive sleep apnoea: effects on atherogenic lipoprotein phenotype.

Patients with obstructive sleep apnoea are at increased risk of atherosclerotic morbidity and mortality. Abnormalities in lipid metabolism that occur in response to chronic intermittent hypoxia in patients with sleep-disordered breathing may increase the cardiovascular risk in an already susceptible population. Atherogenic lipoprotein phenotype and small, dense LDL have an independent predictive role for future cardio- and cerebro-vascular events in patients with the metabolic syndrome. Therefore, testing the hypothesis that therapy of obstructive sleep apnoea may reduce atherogenic lipoprotein phenotype might have significant clinical implications. We suggest that abolition of obstructive …

Effects of statins, fibrates, rosuvastatin, and ezetimibe beyond cholesterol: the modulation of LDL size and subclasses in high-risk patients.

Increasing evidence suggests that the quality-rather than just the quantity-of low-density lipoproteins (LDLs) exerts a great influence on cardiovascular risk. LDLs comprise multiple subclasses with discrete size and density, and different physicochemical composition, metabolic behaviors, and atherogenicity. Individuals generally cluster into 2 broad subgroups. Most have a predominance of large LDLs, and some have a higher proportion of small particles. Small, dense LDLs are good predictors of cardiovascular events and progression of coronary artery disease. Their predominance has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Tre…

Lipid triad or atherogenic lipoprotein phenotype: a role in cardiovascular prevention?

The term "lipid triad" or "atherogenic lipoprotein phenotype" has been introduced to describe a common form of dyslipidemia, characterized by three lipid abnormalities: increased plasma triglyceride levels, decreased HDL-cholesterol concentrations and the presence of small, dense LDL particles. It has been suggested that the clinical importance of the atherogenic lipoprotein phenotype probably exceeds that of LDL-cholesterol, because many more patients with coronary artery disease are found to have this trait than hypercholesterolaemia. There is a body of evidence that therapies effective against plasma HDL-cholesterol and triglycerides are associated with a strong reduction of cardiovascul…

Low-density lipoprotein size and cardiovascular risk assessment

A predominance of small, dense low-density lipoproteins (LDL) has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart disease and evidences suggests that both quality (particularly small, dense LDL) and quantity may increase cardiovascular risk. However, other authors have suggested that LDL size measurement does not add information beyond that obtained by measuring LDL concentration, triglyceride levels and HDL concentrations. Therefore, it remains debatable whether to measure LDL particle size in cardiovascular …

Atherogenic lipoprotein phenotype and LDL size and subclasses in women with gestational diabetes.

AIMS: Women with gestational diabetes are more likely to develop Type 2 diabetes and cardiovascular disease after pregnancy; however, the exact nature of the lipid alterations present is not clear. In Mediterranean women with gestational diabetes, we measured low-density lipoprotein (LDL) size and all seven subclasses, as well as the 'atherogenic-lipoprotein phenotype'[ALP, e.g. concomitant presence of elevated triglycerides, reduced high-density lipoprotein (HDL)-cholesterol and increased small, dense LDL]. METHODS: In 27 women with gestational diabetes and 23 healthy pregnant women matched for age, weeks of gestation and body mass index, we measured plasma lipids and LDL size and subclass…

Gemfibrozil reduces small low-density lipoprotein more in normolipemic subjects classified as low-density lipoprotein pattern B compared with pattern A.

We tested the hypothesis that gemfibrozil has a differential effect on low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subclass distributions and postprandial lipemia that is different in subjects classified as having LDL subclass pattern A or LDL pattern B who do not have a classic lipid disorder. Forty-three normolipemic subjects were randomized to gemfibrozil (1,200 mg/day) or placebo for 12 weeks. Lipids and lipoproteins were determined by enzymatic methods. The mass concentrations of lipoproteins in plasma were determined by analytic ultracentrifugation and included the S(f) intervals: 20 to 400 (very LDL), 12 to 20 (intermediate-density lipoprotein), 0 to 12 (LDL), an…

Atherogenic lipoprotein phenotype and LDL size and subclasses in drug-naïve patients with early rheumatoid arthritis.

Abstract Objective : Subjects with rheumatoid arthritis (RA) have increased cardiovascular risk and may show atherogenic forms of dyslipidemia. The present study investigated whether patients with early RA, beyond alterations in plasma lipids, also show lower LDL size and altered LDL subclass distribution. Design and Methods We identified 25 subjects with RA (47±8 years, body mass index (BMI) 25±4kg/m 2 ) by the American College of Rheumatology diagnostic criteria, with a disease durations Results As compared to controls RA patients had higher plasma triglycerides (1.8±0.5 vs. 1.0±0.5mmol/L, p p =0.0027), while total- and LDL-cholesterol concentrations were similar. LDL particle size was lo…

Update on the role of the atherogenic lipoprotein phenotype in cardiovascular prevention

Higher plasma triglyceride levels and decreased HDL-cholesterol concentrations are usually accompanied by the presence of small, dense LDL in the so-called lipid triad or ‘atherogenic lipoprotein phenotype’. This phenotype is highly atherogenic and its prevalence may suggest an even higher overall burden of atherosclerotic disease as compared with that associated with hypercholesterolemia. As stated by the National Cholesterol Education Program Adult Treatment Panel III, there is evidence suggesting each component of this lipid triad is individually atherogenic. However, the relative contribution of each component cannot be easily determined. Therefore, it has been suggested to consider th…

Size and subclasses of low-density lipoproteins in patients with obstructive sleep apnea.

Patients with obstructive sleep apnea (OSA) have proatherogenic dyslipidemia. We analyzed predictors of low-density lipoproteins' (LDLs) size in patients with OSA. In a cross-sectional study including 58 participants with OSA (30 without the metabolic syndrome [MetS] and 28 with MetS), we evaluated the size of LDL by gradient gel electrophoresis. Compared with patients without the MetS, those with MetS showed lower LDL size ( P = .007), due to a reduction in large LDL-I particles ( P = .002) and an increase in small, dense LDL-IIIA ( P = .048) and LDL-IIIB ( P = .037). The size of LDL correlated inversely with age ( r = −.268, P = .042) and serum triglycerides ( r = −.364, P = .005), and p…

Ezetimibe alone or in combination with simvastatin increases small, dense low-density lipoproteins in healthy men: a randomized trial

Aims The predominance of small dense low-density lipoproteins (sdLDLs) has been associated with increased cardiovascular risk. The effect of ezetimibe on LDL subfraction distribution has not been fully elucidated. This study assessed by gradient gel electrophoresis the effects of ezetimibe alone, simvastatin alone, and their combination on sdLDL subfraction distribution. Methods and results A single-centre, randomized, parallel three-group open-label study was performed in 72 healthy men with a baseline LDL-cholesterol (LDL-C) concentration of 111 ± 30 mg/dL (2.9 ± 0.8 mmol/L). They were treated with ezetimibe (10 mg/day, n = 24), simvastatin (40 mg/day, n = 24), or their combination ( n = …

The differential effects of thiazolidindiones on atherogenic dyslipidemia in type 2 diabetes: what is the clinical significance?

Diabetic dyslipidemia is typically characterized by an increase in plasma triglycerides, a decrease in high-density lipoprotein cholesterol and a concomitant increase in atherogenic small dense low-density lipoproteins. Thiazolidindiones are able to lower the levels of fasting glucose and glycated hemoglobin significantly by improving insulin sensitivity, as well as improving some aspects of diabetic dyslipidemia: total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol tend to increase while triglycerides are generally decreased.This paper reviewed the effects of pioglitazone and rosiglitazone on atherogenic diabetic dyslipidemia, in particular on sma…

&amp;#x201C;European Panel On Low Density Lipoprotein (LDL) Subclasses&amp;#x201D;: A Statement on the Pathophysiology, Atherogenicity and Clinical Significance of LDL Subclasses: Executive Summary

An update on the relationships between rheumatoid arthritis and atherosclerosis

Rheumatoid arthritis is a chronic inflammatory disease. Cardiovascular events are the most important cause of mortality and morbidity in patients with rheumatoid arthritis. Beyond the traditional cardiovascular risk factors, chronic systemic inflammation has been shown to be a crucial factor in atherosclerosis development and progression from endothelial dysfunction to plaque rupture and thrombosis. Many studies have shown that atherosclerosis is not a passive event like accumulation of lipids in the vessel walls; by contrast, it represents an active inflammation of the vessels. Inflammatory cells such as macrophages, monocytes and T cells play important roles in the development of both rhe…

The clinical significance of small, dense low-density lipoproteins

Peak size of low-density lipoproteins (LDL) in humans does not show a normal, but a bimodal distribution and can be separated into two phenotypes, that differ in size, density, physicochemical composition, metabolic behavior, and atherogenicity. These phenotypes have been assigned as pattern A when larger, more buoyant LDL and pattern B when smaller, more dense LDL predominate. Small dense LDL correlates negatively with plasma HDL levels and positively with plasma triglyceride concentrations and is associated with the metabolic syndrome and increased risk for cardiovascular disease. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart diseas…

How should we manage atherogenic dyslipidemia in women with polycystic ovary syndrome?

Despite their young age, women with polycystic ovary syndrome (PCOS) have increased cardiovascular risk. Besides normal concentrations of low-density lipoprotein (LDL) cholesterol, dyslipidemia is very common and includes elevated triglyceride levels and low high-density lipoprotein cholesterol concentrations. Recent findings also showed that women with PCOS have qualitative LDL alterations, with increased levels of atherogenic small, dense LDL particles. Such lipid abnormalities constitute a common form of dyslipidemia, the so-called atherogenic lipoprotein phenotype (ALP), associated with a greater cardiovascular risk. Weight reduction and increased physical activity may constitute first-…

Glucose lowering and anti-atherogenic effects of incretin-based therapies: GLP-1 analogues and DPP-4-inhibitors

Type 2 diabetes is a chronic, progressive disease with a multi-faceted pathophysiology. Beyond the known defects of insulin resistance and beta-cell insufficiency, derangement of incretin hormones normally produced from the gut wall in response to food intake play an important role. In recent years, the 'incretin-based' therapies (IBTs) have been developed to address hyperglycemia through either mimicking the action of the endogenous incretin glucagon-like polypeptide (GLP-1) (GLP-1 receptor agonists) or by inhibiting the activity of the enzyme that degrades GLP-1 (the dipeptyl peptidase-4 inhibitors).We reviewed available evidence on the glucose lowering and anti-atherogenic effects of IBT…

Who needs to care about small, dense low-density lipoproteins?

Summary Background:  Increasing evidence suggest that the ‘quality’ rather than only the ‘quantity’ of low-density lipoprotein (LDL) exerts a great influence on the cardiovascular risk. Small, dense LDL seem to be an important predictor of cardiovascular events and progression of coronary artery disease (CAD) and their predominance has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. Discussion:  Some studies showed in past years that small, dense LDL are usually elevated in patients at very high cardiovascular risk, such as those with CAD and type 2 diabetes. More recently elevated levels of these particles hav…

Small, dense low-density-lipoproteins and the metabolic syndrome.

Small, dense low-density-lipoproteins (LDL) are associated with increased risk for cardiovascular diseases and diabetes mellitus and a reduction in LDL size has been reported in patients with coronary and non-coronary forms of atherosclerosis. LDL size has been accepted as an important predictor of cardiovascular events and progression of coronary artery disease as well as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. Small, dense LDL, with elevated triglyceride levels and low HDL-cholesterol concentrations, constitute the 'atherogenic lipoprotein phenotype (ALP)', a form of atherogenic dyslipidemia that is a feature of type …

Should we measure routinely oxidised and atherogenic dense low-density lipoproteins in subjects with type 2 diabetes?

Beyond low-density lipoprotein (LDL)-cholesterol concentrations, in recent years, several clinical studies have shown that both oxidised and small, dense LDL have a strong predictive role for the presence of vascular atherosclerosis. These two lipid parameters seem to have a synergistic impact on cardiovascular risk, with a greater importance in patients at higher-risk, such as those with type-2 diabetes. Increased levels of oxidised and small, dense LDL levels are a feature of diabetic dyslipidaemia, and small, dense LDL have been shown to be a good predictor of future cardiovascular events, at both univariate and multivariate analyses. On the other hand, although the association of oxidis…

Recent Insights on Dark Chocolate Consumption and Cardiovascular Risk

Long-term consequences of polycystic ovary syndrome on cardiovascular risk

Most available data suggest that the prevalence of cardiovascular diseases in women with polycystic ovary syndrome (PCOS) is smaller than expected based on risk calculations during fertile years; therefore, more studies are needed on long-term cardiovascular consequences. Evidence is accumulating that postmenopausal women with PCOS have an increased risk of cerebrovascular events and cardiovascular morbidity. These events are partially related to persisting hyperandrogenism but are mostly correlated with excessive body weight (mainly visceral obesity); this suggests that our best long-term strategy is to ensure that women with PCOS are informed about their high risk for metabolic and cardio…

Do we need better lipid tools for cardiovascular risk assessment ?

Atherogenic lipoprotein phenotype and low-density lipoprotein size and subclasses in patients with growth hormone deficiency before and after short-term replacement therapy

Objective: Patients with growth hormone deficiency (GHD) have increased cardiovascular risk and may show elevated triglyceride and reduced high density lipoprotein (HDL) cholesterol concentrations, two lipid abnormalities usually accompanied by increased small dense LDL in the ‘atherogenic lipoprotein phenotype’ (ALP). In the present study, we directly investigated (1) whether hypopituitary patients with GHD have increased small dense LDL; (2) whether growth hormone replacement therapy (GHRT) beneficially impact on such particles; (3) the prevalence of ALP in GHD and GHRT patients. Design and methods: In 14 hypopituitary patients with GHD (44 ± 13 years, body mass index (BMI) 27 ± 3) before…

The effects of ezetimibe on LDL-cholesterol: quantitative or qualitative changes ?

Ezetimibe represents the first of a new class of agents, the cholesterol absorption inhibitors, able to reduce low-density lipoproteins (LDL)-cholesterol by 15-25% from baseline in monotherapy and on top of statins and fibrates. To-date all the data regarding the efficacy of ezetimibe comes from the studies of its lipid-lowering power. Yet, recent findings from the ENHANCE study on atherosclerosis progression showed that the addition of ezetimibe to simvastatin in patients with heterozygous familial hypercholesterolemia did not affect the mean change in carotid intima-media thickness, although a significant reduction in LDL-cholesterol levels was present. Therefore, we cannot exclude that e…

The predictive role of atherogenic dyslipidemia in subjects with non-coronary atherosclerosis

Abstract Background Recent findings have suggested that subjects with non-coronary atherosclerosis may show elevated prevalence of atherogenic dyslipidemia, including higher triglyceride levels, reduced HDL-cholesterol concentrations and increased levels of small, dense low-density lipoproteins (LDL). These three lipid abnormalities constitute the so-called “atherogenic-lipoprotein-phenotype” (ALP) but its predictive role in these patients still remains to be established. Methods We performed a 2-year follow-up study to assess clinical and biochemical predictors of cardiovascular events in 44 male patients (64 ± 5 years, BMI: 27 ± 3), 26 with peripheral arterial disease and 18 with abdomina…

Interleukin-18 levels are associated with low-density lipoproteins size

INTRODUCTION: Both low-density lipoproteins (LDL) size and serum interleukin (IL)-18 levels have been shown to be predictors of cardiovascular morbidity and mortality. However, it is still unknown whether IL-18 levels are independently associated with LDL size. METHODS: In this cross-sectional study including 53 premenopausal women (18-45 years), LDL size (by gradient gel electrophoresis), serum IL-18, high-sensitivity C-reactive protein (hs-CRP), serum lipids, insulin sensitivity (S(I), by frequently sampled intravenous glucose tolerance test) were measured. RESULTS: LDL size correlated with IL-18 (r = -0.38, P = 0.006), hs-CRP (r = -0.40, P = 0.003), S(I) (r = 0.36, P = 0.011), serum trig…

Atherogenic lipoprotein phenotype and LDL size and subclasses in patients with peripheral arterial disease

The type of dyslipidemia in patients with peripheral arterial disease (PAD) is still ill defined. PAD patients often show elevated triglycerides and reduced HDL-cholesterol, two lipid abnormalities usually accompanied by decreased LDL size in the "atherogenic lipoprotein phenotype" (ALP). We investigated (1) whether PAD patients have lower LDL size, (2) altered LDL subclass distribution and (3) the prevalence of ALP. We measured plasma lipids and LDL size and subclasses by gradient gel electrophoresis in 31 adults with intermittent claudication and 31 age-BMI-matched controls. Patients had higher prevalence of hypertension (p = .0132), smoking (p < .0020) and diabetes (p = .0024), with lowe…

The Role of Small, Dense Low-Density-Lipoproteins in Non-Coronary Forms of Atherosclerosis

Small, dense low density lipoproteins (LDL) are associated with increased risk for cardiovascular disease and seem to be an important predictor of cardiovascular events and progression of coronary artery disease. In addition, the predominance of small dense LDL has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III). Less data is available on the role of LDL size in the prevention of vascular diseases, including peripheral arterial disease, carotid artery disease and abdominal aortic aneurysm. The NCEP-ATP III stated that clinical non-coronary atherosclerosis carries a risk for coronary heart disease …