Progression of carotid intima-media thickness as predictor of vascular events: results from the IMPROVE study.

OBJECTIVE: To investigate whether several different measures of carotid intima-media thickness (IMT) progression are associated with subsequent vascular events and whether such associations are independent of baseline carotid atherosclerotic profile and Framingham risk factors. APPROACH AND RESULTS: A longitudinal cohort study (the Carotid Intima Media Thickness [IMT] and IMT-Progression as Predictors of Vascular Events in a High Risk European Population study) was performed in 7 centers in 5 European countries (Finland, France, Italy, the Netherlands, and Sweden). Three thousand four hundred eighty-two subjects (median age 64.1 years; 47.8% men) with ≥ 3 vascular risk factors were recruited and monitored for a postprogression median follow-up of 21.5 months, during which time 129 subjects experienced a first vascular event (incidence of 20.4 per 1000 person-years). The 15th month progression of mean and maximum carotid IMT of the left and right common carotids, bifurcations, internal carotid arteries, and their composite measures, as well as the fastest IMTmax progression (Fastest-IMT(max-progr)) detected in the whole carotid tree regardless of location, were used in statistical analyses. All carotid IMT measures showed significant progression during the first 15 months (P<0.001), but only the Fastest-IMT(max-progr) was significantly associated with the risk of subsequent vascular events. The Fastest-IMT(max-progr) association persisted after Bonferroni correction for multiple comparisons and after adjustments for Framingham risk factors and pharmacological treatments (all P<0.005). The use of Framingham Risk Score in place of Framingham risk factors provided almost identical results (P=0.003). CONCLUSIONS: The Fastest-IMT(max-progr), a novel approach to assess carotid IMT progression, identifies focal increases of carotid IMT and, in contrast to other progression variables, is associated with cardiovascular risk.

Cross-sectional analysis of baseline data to identify the major determinants of carotid intima-media thickness in a European population: the IMPROVE study.

AIMS: The 'IMPROVE study' was designed to investigate whether cross-sectional carotid artery intima-media thickness (IMT) and overall IMT progression are predictors of new vascular events in European individuals at high risk of cardiovascular diseases. This paper reports the results of the baseline analyses aimed at identifying the major determinants of increased carotid IMT (C-IMT). METHODS AND RESULTS: IMPROVE is a prospective, multicentre, longitudinal, observational study. A total of 3711 subjects (age range 54-79 years) with at least three vascular risk factors (VRFs) were recruited in seven centres in Finland, France, Italy, the Netherlands, and Sweden. Collected variables included clinical, biochemical, genetic, socioeconomic, psychological, nutritional, and educational data, personal and family history of diseases, drug intake, and physical activity. By multiple linear regression analysis, C-IMT was positively associated with latitude, age, gender, pulse pressure, pack-years, and hypertension, and inversely with educational level (all P < 0.0001 for IMT(mean-max)). Latitude was the strongest independent determinant of C-IMT (partial r(2) for IMT(mean-max) = 0.109, P < 0.0001) and alone accounted for nearly half of the variation explained by the regression model (partial r(2) for IMT(mean-max) = 0.243, P < 0.0001). The geographical gradient for C-IMT paralleled the well-known north-to-south cardiovascular mortality gradient (r(2) for IMT(mean) = 0.96). CONCLUSION: Latitude is an important determinant of C-IMT, which is not explained by between-country differences in established VRFs. Other unknown contributory mechanisms such as heritable, nutritional, or environmental factors may be important in the genesis of this geographical gradient.

Chocolate, lifestyle, and health.

Interest in the biological activities of cocoa polyphenols is increasing steadily. In fact, the high polyphenol content of cocoa, coupled with its widespread presence in many food items, render this food of particular interest from the nutritional and "pharmacological" viewpoints. This paper summarizes the new findings and developments regarding the effects of cocoa and chocolate consumption on human health as presented at the International Conference "Chocolate, Lifestyle, and Health" (Milan, Italy, March 2, 2007) regarding the effects of cocoa and chocolate consumption on human health.

Non-pharmacological control of plasma cholesterol levels.

The importance of non-pharmacological control of plasma cholesterol levels in the population is increasing, along with the number of subjects whose plasma lipid levels are non-optimal, or frankly elevated, according to international guidelines. In this context, a panel of experts, organized and coordinated by the Nutrition Foundation of Italy, has evaluated the nutritional and lifestyle interventions to be adopted in the control of plasma cholesterol levels (and specifically of LDL cholesterol levels). This Consensus document summarizes the view of the panel on this topic, with the aim to provide an updated support to clinicians and other health professionals involved in cardiovascular prevention.

Levels of the n-3 fatty acid eicosapentaenoic acid in addition to those of alpha linolenic acid are significantly raised in blood lipids by the intake of four walnuts a day in humans.

BACKGROUND AND AIMS: Ingestion of alpha linolenic acid (ALA), with the richest source among dry fruits such as walnuts, is associated with cardiovascular prevention. The aim of this study was to selectively evaluate the effects of moderate walnut consumption on the levels of ALA and its metabolic derivatives in human blood. METHODS AND RESULTS: After a 2-week run-in period, 10 volunteers consumed 4 walnuts per day (in addition to their habitual diet) for 3 weeks. Fatty acid profiles, with special attention to levels of ALA and long chain polyunsaturated fatty acids (LC-PUFA), were assessed in blood drops collected from fingertips. The data indicate that the administration of a few walnuts a day for 3 weeks significantly increases blood levels, not only of ALA (from 0.23+/-0.07 SD to 0.47+/-0.13 SD), but also of its longer chain derivative eicosapentaenoic acids (EPA) (from 0.23+/-0.37 to 0.82+/-0.41) with levels remaining elevated over basal values after washout. CONCLUSION: The findings of this pilot study indicate that plant ALA in appropriate food items favourably affects the n-3 LC-PUFA status.

Rosuvastatin, but not simvastatin, provides end-organ protection in stroke-prone rats by antiinflammatory effects.

OBJECTIVE: Brain abnormalities, preceded by a systemic inflammation, develop in spontaneously hypertensive stroke-prone rats (SHRSP). In this model, we investigated whether the hydrophilic statin, rosuvastatin, influences the development of inflammation associated with brain abnormalities. Because differences in hydrophilicity/hydrophobicity contribute to the differences in statin pharmacology, we also evaluated the effects of simvastatin, a lipophilic molecule METHODS AND RESULTS: SHRSP, fed a high-salt diet, were treated long-term with vehicle or rosuvastatin (1 and 10 mg/kg per day). Brain abnormalities developed after 40+/-5 days and after 60+/-5 days of salt loading, in vehicle-treated and in rosuvastatin-treated (1 mg/kg per day) SHRSP, respectively. After 100 days of treatment, no damage was detectable in 30% of the rats treated with the highest dose of the drug. In comparison with vehicle-treated SHRSP, rosuvastatin treatment attenuated the transcription of monocyte chemoattractant protein-1, transforming growth factor-beta1, IL-1beta, and tumor necrosis factor-alpha in the kidney, and of P-selectin in brain vessels and increased the transcription of endothelial nitric oxide synthase mRNA in the aorta. Urinary excretion of acute-phase proteins increased with time in vehicle-treated animals but remained negligible in drug-treated animals. These effects are independent of changes in physiological parameters. Treatment of SHRSP with simvastatin (2 to 20 mg/kg per day) did not exert any protective effect. CONCLUSIONS: Rosuvastatin attenuates inflammatory processes associated with cerebrovascular disease.

Metabolic syndrome, inflammation and atherosclerosis.

The inflammatory component of atherogenesis has been increasingly recognized over the last decade. Inflammation participates in all stages of atherosclerosis, not only during initiation and during evolution of lesions, but also with precipitation of acute thrombotic complications. The metabolic syndrome is associated with increased risk for development of both cardiovascular disease and type-2 diabetes in humans. Central obesity and insulin resistance are thought to represent common underlying factors of the syndrome, which features a chronic low-grade inflammatory state. Diagnosis of the metabolic syndrome occurs using defined threshold values for waist circumference, blood pressure, fasting glucose and dyslipidemia. The metabolic syndrome appears to affect a significant proportion of the population. Therapeutic approaches that reduce the levels of proinflammatory biomarkers and address traditional risk factors are particularly important in preventing cardiovascular disease and, potentially, diabetes. The primary management of metabolic syndrome involves healthy lifestyle promotion through moderate calorie restriction, moderate increase in physical activity and change in dietary composition. Treatment of individual components aims to control atherogenic dyslipidemia using fibrates and statins, elevated blood pressure, and hyperglycemia. While no single treatment for the metabolic syndrome as a whole yet exists, emerging therapies offer potential as future therapeutic approaches.

Safety of statins: focus on clinical pharmacokinetics and drug interactions.

Statin monotherapy is generally well tolerated, with a low frequency of adverse events. The most important adverse effects associated with statins are myopathy and an asymptomatic increase in hepatic transaminases, both of which occur infrequently. Because statins are prescribed on a long-term basis, however, possible interactions with other drugs deserve particular attention, as many patients will typically receive pharmacological therapy for concomitant conditions during the course of statin treatment. This review summarizes the pharmacokinetic properties of statins and emphasizes their clinically relevant drug interactions.

Inflammation in atherosclerosis and implications for therapy.

Atherosclerosis is now understood to be a disease characterized by inflammation that results in a host of complications, including ischemia, acute coronary syndromes (unstable angina pectoris and myocardial infarction), and stroke. Inflammation may be caused by a response to oxidized low-density lipoproteins, chronic infection, or other factors; and markers of this process, such as C-reactive protein, may be useful to predict an increased risk of coronary heart disease. Thus, we believe that inflammatory processes may be potential targets of therapy in preventing or treating atherosclerosis and its complications.

Treatment with statins after induction of focal ischemia in rats reduces the extent of brain damage.

OBJECTIVE: In the present study, MRI has been used to investigate therapeutic intervention with statins in a model of permanent focal cerebral ischemia in rat. METHODS AND RESULTS: Brain ischemia was induced in rats by the permanent occlusion of middle cerebral artery (MCAO) and the brain infarct size followed up in alive animals 2, 24, and 48 hours after MCAO, using the trace of apparent diffusion coefficient [Tr(D)] maps and T2-weighted images. In vehicle-treated rats, the infarct volumes increased by 38.5% and 89% after 24 and 48 hours, respectively, compared with the damage detected at 2 hours after MCAO. Treatment with simvastatin (20 mg/kg) after MCAO prevented the increase in brain infarct volume occurring at 24 hours and induced a 46.6% reduction after 48 hours. This effect was similar to that observed when simvastatin was administered before the induction of focal ischemia. T2W-MRI images confirmed these findings. The neuroprotective effects of simvastatin were paralleled by an increase in endothelial NO synthase immunoreactivity, detectable in the brain of simvastatin-treated rats. CONCLUSIONS: Statins, in addition to their preventive effect on cerebral ischemia, exert a neuroprotective role in the attenuation of brain damage after acute stroke.

Smoking and gender.

Smoking is a major cause of coronary heart disease for both men and women and a positive correlation between tobacco use and cerebrovascular disease has been also described. In addition, cigarette smoking is the most powerful risk factor predisposing to atherosclerotic peripheral artery disease. More recently, passive smoking has been also shown to represent an important risk factor for coronary artery disease. Moreover, the incidence of coronary artery and cerebrovascular diseases in ex-smokers consistently decreases after cessation, further underlying the relevance of smoking as a risk factor for these pathological conditions. The effects of cigarette smoking on atherosclerosis initiation and progression as well on its complications are mostly responsible for the enhanced cardio- and cerebrovascular risk observed in smoking compared to non-smoking subjects. Since hormonal status may also play a role in the development and stability of the atherosclerotic plaque, smoking habits could influence the clinical complications of atheroclerosis in a gender dependent manner. Up to now, however, few studies have investigated the relative importance of smoking as a risk factor for fatal and non-fatal diseases in the two sexes within the same study population. On the basis of available clinical data, this review will discuss the risk of fatal and non-fatal diseases among smoking men and women with special emphasis on cardiovascular and cerebrovascular disease which also represents the most common cause of death among smokers. A description of the mechanisms involved in the tobacco-induced atherosclerotic damage will be also given in order to underline possible gender-related differences.

New insights into brain damage in stroke-prone rats: a nuclear magnetic imaging study.

BACKGROUND AND PURPOSE: The spontaneously hypertensive stroke-prone rat (SHRSP) is an animal model for a complex form of cerebrovascular pathology. MRI provides an efficient and noninvasive tool for studying the time course of brain damage. The aim of this study was to gain new insights into the pathological phenomena responsible for the occurrence of brain injury in SHRSP with the use of the apparent diffusion coefficient of water (ADC), one of the most efficient MRI parameters for detecting brain abnormalities. To this end, the pattern of ADC variation observed in SHRSP was compared with that of focal ischemia induced in both SHRSP and Sprague-Dawley rats. METHODS: Four groups of animals were studied: SHRSP developing spontaneous brain lesions fed with a salt-loaded (n=15, group 1) or standard diet (n=3, group 2) and Sprague-Dawley rats (n=8, group 3) and SHRSP (n=8, group 4) with permanent middle cerebral artery occlusion. ADC maps and T2-weighted images of brains were performed by MRI. After the rats were killed, the brains were removed and histologically processed. RESULTS: There was no decrease in ADC during spontaneous stroke in the SHRSP fed with a normal or salt-enriched diet, while both the SHRSP and Sprague-Dawley rats with middle cerebral artery occlusion showed a marked decrease that lasted for 24 to 48 hours. CONCLUSIONS: Cerebral ischemia cannot be considered a major factor in the onset of spontaneous brain lesions in SHRSP, which show only vasogenic edema after the beginning of the damage with no evidence of metabolic impairment.

Cholesterol-induced thrombogenicity of the vessel wall: inhibitory effect of fluvastatin.

High cholesterol levels are a known risk factor for coronary events. The molecular links between high serum cholesterol and the increased thrombogenicity of the arterial wall are still matter of investigation. In the present study we investigate the relationship between plasma cholesterol, thrombus formation and TF expression in a atherosclerotic rabbit model. Hypercholesterolemic rabbits showed a pronounced TF staining as well as NF-kappaB activation in the aortic arch. A consistent vessel wall platelet deposition was also observed. Treatment with fluvastatin reduced lipid accumulation, TF overexpression (-60%), NF-kappaB activation, and platelet deposition (-56%). In vitro studies showed that the drug upregulated IkappaB alpha in unstimulated as well as in TNFalpha-stimulated cells and also impaired the TNFalpha-induced Cdc42 prenylation, indicating that fluvastatin interferes with the transcriptional activation of TF gene. These results indicate that the prothrombotic phenotype of arterial wall, associated with elevated serum cholesterol levels, is mediated by TF overexpression. Fluvastatin treatment reduces the prothrombotic tendency by inhibiting TF synthesis.

Efficacy of rosuvastatin 10 mg in patients with the metabolic syndrome.

The constellation of risk factors known as the metabolic syndrome increases the risk of coronary artery disease at any low-density lipoprotein (LDL) cholesterol level. We performed an exploratory analysis of data from 5 trials to study the effects of rosuvastatin 10 mg on lipid levels and ratios in hypercholesterolemic patients (LDL cholesterol > or =160 mg/dL and <250 mg/dL) who met a modified National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) definition of the metabolic syndrome. Of 580 patients completing 12 weeks of treatment with rosuvastatin 10 mg, 194 (33%) met the definition of the metabolic syndrome by exhibiting > or =3 of the following: body mass index >30; triglycerides > or =150 mg/dL; high-density lipoprotein (HDL) cholesterol <40 mg/dL in men and <50 mg/dL in women; blood pressure > or =130/> or =85 mm Hg or receiving current medication for hypertension; and fasting blood glucose > or =110 mg/dL. Patients with the metabolic syndrome had higher triglyceride, non-HDL cholesterol, apolipoprotein B, and lipid ratios, and lower HDL cholesterol and apolipoprotein A-I levels, at baseline compared with patients without the metabolic syndrome. In patients with the metabolic syndrome, rosuvastatin 10 mg improved LDL cholesterol (-47%), non-HDL cholesterol (-43%), non-HDL cholesterol/HDL cholesterol ratio (-47%), apolipoprotein B (-37%), apolipoprotein B/apolipoprotein A-I ratio (-40%), triglycerides (-23%), apolipoprotein A-I (+7%), and HDL cholesterol (+10%)-in a manner similar to that in hypercholesterolemic patients who did not meet these criteria. Among patients who met the metabolic syndrome criteria and who had triglycerides > or =200 mg/dL, 64% met their ATP III non-HDL goals.

Ajoene, a garlic compound, inhibits protein prenylation and arterial smooth muscle cell proliferation.

(1) Ajoene is a garlic compound with anti-platelet properties and, in addition, was shown to inhibit cholesterol biosynthesis by affecting 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase and late enzymatic steps of the mevalonate (MVA) pathway. (2) MVA constitutes the precursor not only of cholesterol, but also of a number of non-sterol isoprenoids, such as farnesyl and geranylgeranyl groups. Covalent attachment of these MVA-derived isoprenoid groups (prenylation) is a required function of several proteins that regulate cell proliferation. We investigated the effect of ajoene on rat aortic smooth muscle cell proliferation as related to protein prenylation. (3) Cell counting, DNA synthesis, and cell cycle analysis showed that ajoene (1-50 micro M) interfered with the progression of the G1 phase of the cell cycle, and inhibited rat SMC proliferation. (4) Similar to the HMG-CoA reductase inhibitor simvastatin, ajoene inhibited cholesterol biosynthesis. However, in contrast to simvastatin, the antiproliferative effect of ajoene was not prevented by the addition of MVA, farnesol (FOH), and geranylgeraniol (GGOH). Labelling of smooth muscle cell cellular proteins with [3H]-FOH and [3H]-GGOH was significantly inhibited by ajoene. (5) In vitro assays for protein farnesyltransferase (PFTase) and protein geranylgeranyltransferase type I (PGGTase-I) confirmed that ajoene inhibits protein prenylation. High performance liquid chromatography (HPLC) and mass spectrometry analyses also demonstrated that ajoene causes a covalent modification of the cysteine SH group of a peptide substrate for protein PGGTase-I. (6) Altogether, our results provide evidence that ajoene interferes with the protein prenylation reaction, an effect that may contribute to its inhibition of SMC proliferation.

Pharmacological interactions of statins.

The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) are effective in reducing the risk of coronary events, and are generally very well tolerated. However, simvastatin, lovastatin, cerivastatin and atorvastatin are biotransformed in the liver primarily by cytochrome P450 (CYP) 3A4, and clinical experience has shown that the risk of adverse effect, such as myopathy, increases with concomitant use of statins with drugs that substantially inhibit CYP 3A4 at therapeutic doses. Indeed, pharmacokinetic interactions (e.g. increased bioavailability), myositis, and rhabdomyolysis have been reported following concurrent use of atorvastatin, cerivastatin, simvastatin or lovastatin and cyclosporine A, mibefradil or nefazodone. In contrast, fluvastatin (mainly metabolized by CYP 2C9) and pravastatin (eliminated by other metabolic routes) are less subject to this interaction. Nevertheless, an increase in pravastatin bioavailability has been reported in the presence of cyclosporine A, possibly because of an interaction at the level of biliary excretion. In summary, some statins may have lower adverse drug interaction potential than others, which is an important determinant of safety during long-term therapy.

Efficacy and safety of plant stanols and sterols in the management of blood cholesterol levels.

Foods with plant stanol or sterol esters lower serum cholesterol levels. We summarize the deliberations of 32 experts on the efficacy and safety of sterols and stanols. A meta-analysis of 41 trials showed that intake of 2 g/d of stanols or sterols reduced low-density lipoprotein (LDL) by 10%; higher intakes added little. Efficacy is similar for sterols and stanols, but the food form may substantially affect LDL reduction. Effects are additive with diet or drug interventions: eating foods low in saturated fat and cholesterol and high in stanols or sterols can reduce LDL by 20%; adding sterols or stanols to statin medication is more effective than doubling the statin dose. A meta-analysis of 10 to 15 trials per vitamin showed that plasma levels of vitamins A and D are not affected by stanols or sterols. Alpha carotene, lycopene, and vitamin E levels remained stable relative to their carrier molecule, LDL. Beta carotene levels declined, but adverse health outcomes were not expected. Sterol-enriched foods increased plasma sterol levels, and workshop participants discussed whether this would increase risk, in view of the marked increase of atherosclerosis in patients with homozygous phytosterolemia. This risk is believed to be largely hypothetical, and any increase due to the small increase in plasma plant sterols may be more than offset by the decrease in plasma LDL. There are insufficient data to suggest that plant stanols or sterols either prevent or promote colon carcinogenesis. Safety of sterols and stanols is being monitored by follow-up of samples from the general population; however, the power of such studies to pick up infrequent increases in common diseases, if any exist, is limited. A trial with clinical outcomes probably would not answer remaining questions about infrequent adverse effects. Trials with surrogate end points such as intima-media thickness might corroborate the expected efficacy in reducing atherosclerosis. However, present evidence is sufficient to promote use of sterols and stanols for lowering LDL cholesterol levels in persons at increased risk for coronary heart disease.

Plasma low-density lipoprotein cholesterol and bone mass densitometry in postmenopausal women.

OBJECTIVE: The prevalence and the clinical and social importance of osteopenia and osteoporosis are increasing in western societies. To improve knowledge of the risk factors associated with these conditions, we assessed the relationship between bone mass density and plasma lipid profile in a cohort of postmenopausal women. METHODS: We studied 1303 postmenopausal women who attended a menopause outpatient clinic. All women underwent bone mineral density determination at the level of the lumbar spine. Plasma lipids and lipoproteins and bone metabolic markers were assessed on a blood sample obtained after a 12-hour fast. RESULTS: Statistically significant associations were found by univariate analysis between prevalence of osteopenia and age, time since menopause, body mass index, and low-density lipoprotein (LDL) cholesterol. Specifically, women with plasma LDL cholesterol levels of at least 160 mg/dL had a more than doubled probability of being osteopenic compared with women with lower LDL cholesterol (47.9% versus 21.2%, respectively). Time since menopause, body mass index, and LDL cholesterol were the only variables significantly associated with the prevalence of osteopenia, by multivariable analysis. CONCLUSION: Postmenopausal women with increased plasma LDL cholesterol levels had a greater probability of being classified as osteopenic than women with normal plasma LDL cholesterol levels. Our data, if confirmed, suggest that elevated levels of plasma LDL cholesterol should be regarded as an additional risk factor for reduced bone mineral density.