Association of rheumatoid arthritis disease activity and antibodies to periodontal bacteria with serum lipoprotein profile in drug naive patients

Objective: We investigated lipid concentrations, particle sizes and antibodies binding to periodontal bacteria Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis and to malondialdehyde-acetaldehyde (MAA) modified low-density lipoprotein in immunoglobulin (Ig) class A, G and M among patients with newly diagnosed rheumatoid arthritis (RA) in a population-based cohort.Methods: Concentrations and sizes of lipoprotein particles analysed by proton nuclear magnetic resonance spectroscopy and antibody levels to MAA modified low-density lipoprotein were studied at baseline and after one-year of follow-up. Serum Ig A and G class antibodies to periodontal bacteria were determined at baseline.Results: Sixty-three patients were divided into tertiles according to disease activity by disease activity score with 28 joint count and erythrocyte sedimentation rate (ESR) (<3.9, 3.9-4.7, >4.7). Small low-density lipoprotein concentration was lowest in the tertile with the highest disease activity. In high-density lipoprotein, the concentrations of total, medium and small particles decreased with disease activity. The particle size in low-density lipoprotein associated with disease activity and the presence of antibodies to P. gingivalis. Ig G and M antibodies to MAA modified low-density lipoprotein correlated with disease activity. Inflammation associated changes faded by one year.Conclusions: Drug naive RA patients had proatherogenic changes in lipid profiles, but they were reversible, when inflammation diminished.Key messagesPatients with drug naive rheumatoid arthritis showed proatherogenic lipid profiles.Reversible changes in lipid profiles can be achieved as response to inflammation suppression.Active therapy aimed at remission is essential in all patients with rheumatoid arthritis.

Intake of Fatty Fish Alters the Size and the Concentration of Lipid Components of HDL Particles and Camelina Sativa Oil Decreases IDL Particle Concentration in Subjects with Impaired Glucose Metabolism

SCOPE

Intake of long-chain n-3 PUFAs affects the lipoprotein subclass profile, whereas the effect of shorter chain n-3 PUFAs remains unclear. We investigated the effect of fish and camelina sativa oil (CSO) intakes on lipoprotein subclasses.

METHODS AND RESULTS

Altogether, 79 volunteers with impaired glucose metabolism were randomly assigned to CSO, fatty fish (FF), lean fish (LF), or control group for 12 weeks. Nuclear magnetic resonance spectroscopy was used to determine lipoprotein subclasses and their lipid components. The average HDL particle size increased in the FF group (overall p = 0.032) as compared with the control group. Serum concentrations of cholesterol in HDL and HDL₂ (overall p = 0.024 and p = 0.021, respectively) and total lipids and phospholipids in large HDL particles (overall p = 0.012 and p = 0.019, respectively) increased in the FF group, differing significantly from the LF group. The concentration of intermediate-density lipoprotein (IDL) particles decreased in the CSO group (overall p = 0.033) as compared with the LF group.

CONCLUSION

Our study suggests that FF intake causes a shift toward larger HDL particles and increases the concentration of lipid components in HDL, which may be associated with the antiatherogenic properties of HDL. Furthermore, CSO intake decreases IDL particle concentration. These changes may favorably affect cardiovascular risk.

Effect of PCSK9 Inhibition by Alirocumab on Lipoprotein Particle Concentrations Determined by Nuclear Magnetic Resonance Spectroscopy

BACKGROUND

In patients with discordance between low-density lipoprotein (LDL) cholesterol and LDL particle (LDL-P) concentrations, cardiovascular risk more closely correlates with LDL-P.

METHODS AND RESULTS

We investigated the effect of alirocumab, a fully human monoclonal antibody to proprotein convertase subtilisin/kexin type 9, on lipoprotein particle concentration and size in hypercholesterolemic patients, using nuclear magnetic resonance spectroscopy. Plasma samples were collected from patients receiving alirocumab 150 mg every 2 weeks (n=26) or placebo (n=31) during a phase II, double-blind, placebo-controlled trial in patients (LDL cholesterol ≥100 mg/dL) on a stable atorvastatin dose. In this post hoc analysis, percentage change in concentrations of LDL-P, very-low-density lipoprotein particles, and high-density lipoprotein particles from baseline to week 12 was determined by nuclear magnetic resonance. Alirocumab significantly reduced mean concentrations of total LDL-P (-63.3% versus -1.0% with placebo) and large (-71.3% versus -21.8%) and small (-54.0% versus +17.8%) LDL-P subfractions and total very-low-density lipoprotein particle concentrations (-36.4% versus +33.4%; all P<0.01). Total high-density lipoprotein particles increased with alirocumab (+11.2% versus +1.4% with placebo; P<0.01). There were greater increases in large (44.6%) versus medium (17.7%) or small high-density lipoprotein particles (2.8%) with alirocumab. LDL-P size remained relatively unchanged in both groups; however, very-low-density and high-density lipoprotein particle sizes increased to a significantly greater extent with alirocumab.

CONCLUSIONS

Alirocumab significantly reduced LDL-C and LDL-P concentrations in hypercholesterolemic patients receiving stable atorvastatin therapy. These findings may be of particular relevance to patients with discordant LDL-C and LDL-P concentrations.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov. Unique identifier: NCT01288443.

Lipid-lowering efficacy of atorvastatin

BACKGROUND

This represents the first update of this review, which was published in 2012. Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of atorvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol and triglycerides in individuals with and without evidence of cardiovascular disease. The primary focus of this review was determination of the mean per cent change from baseline of LDL-cholesterol. Secondary objectives • To quantify the variability of effects of various doses of atorvastatin.• To quantify withdrawals due to adverse effects (WDAEs) in placebo-controlled randomised controlled trials (RCTs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 11, 2013), MEDLINE (1966 to December Week 2 2013), EMBASE (1980 to December Week 2 2013), Web of Science (1899 to December Week 2 2013) and BIOSIS Previews (1969 to December Week 2 2013). We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. We collected information on withdrawals due to adverse effects from placebo-controlled trials.

MAIN RESULTS

In this update, we found an additional 42 trials and added them to the original 254 studies. The update consists of 296 trials that evaluated dose-related efficacy of atorvastatin in 38,817 participants. Included are 242 before-and-after trials and 54 placebo-controlled RCTs. Log dose-response data from both trial designs revealed linear dose-related effects on blood total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides. The Summary of findings table 1 documents the effect of atorvastatin on LDL-cholesterol over the dose range of 10 to 80 mg/d, which is the range for which this systematic review acquired the greatest quantity of data. Over this range, blood LDL-cholesterol is decreased by 37.1% to 51.7% (Summary of findings table 1). The slope of dose-related effects on cholesterol and LDL-cholesterol was similar for atorvastatin and rosuvastatin, but rosuvastatin is about three-fold more potent. Subgroup analyses suggested that the atorvastatin effect was greater in females than in males and was greater in non-familial than in familial hypercholesterolaemia. Risk of bias for the outcome of withdrawals due to adverse effects (WDAEs) was high, but the mostly unclear risk of bias was judged unlikely to affect lipid measurements. Withdrawals due to adverse effects were not statistically significantly different between atorvastatin and placebo groups in these short-term trials (risk ratio 0.98, 95% confidence interval 0.68 to 1.40).

AUTHORS' CONCLUSIONS

This update resulted in no change to the main conclusions of the review but significantly increases the strength of the evidence. Studies show that atorvastatin decreases blood total cholesterol and LDL-cholesterol in a linear dose-related manner over the commonly prescribed dose range. New findings include that atorvastatin is more than three-fold less potent than rosuvastatin, and that the cholesterol-lowering effects of atorvastatin are greater in females than in males and greater in non-familial than in familial hypercholesterolaemia. This review update does not provide a good estimate of the incidence of harms associated with atorvastatin because included trials were of short duration and adverse effects were not reported in 37% of placebo-controlled trials.

Lipoprotein concentration, particle number, size and cholesterol efflux capacity are associated with mitochondrial oxidative stress and function in an HIV positive cohort

BACKGROUND

Association of lipoprotein particle size/number and HDL function with mitochondrial oxidative stress and function may underlie the excess cardiovascular (CVD) risk in HIV.

METHODS AND RESULTS

Among HIV infected individuals on stable highly active antiretroviral therapy, we related standard and novel lipid measures [plasma total cholesterol, triglycerides, HDL-C, LDL-C, lipoprotein particle (-P) subclass size and number and HDL function (via cholesterol-efflux capacity)] with oxidative stress [peripheral blood mononuclear cell's mitochondrial-specific 8-oxo-deoxyguanine (8-oxo-dG)] and function markers [oxidative phosphorylation (OXPHOS) NADH dehydrogenase (Complex I) and cytochrome c oxidase (Complex IV) enzyme activities]. Multivariable-adjusted logistic and linear regression analyses were employed adjusting for age, gender, CD4 nadir, viral load, smoking, diabetes, HOMA-IR, hypertension and lipid medications. Among 150 HIV-infected persons (mean age 52 years, 12% women, median CD4 count 524 cell/mm3), low HDL-C and high total cholesterol/HDL-C ratio were related to PBMC 8-oxo-deoxyguanine (p = 0.01 and 0.02 respectively). Large HDL-P and HDL-P size were inversely related to PBMC 8-oxo-deoxyguanine (p = 0.04). Small LDL-P (p = 0.01) and total LDL-P (p = 0.01) were related to decreased OXPHOS Complex I activity. LDL-P was related to decreased OXPHOS Complex IV activity (p = 0.02). Cholesterol efflux capacity was associated with increased OXPHOS Complex IV activity.

CONCLUSIONS

HDL concentration and particle size and number are related to decreased PBMC mitochondrial oxidative stress whereas HDL function is positively related to mitochondrial oxidative function. The association we find between atherogenic lipoprotein profile and increased oxidative stress and function suggests these pathways may be important in the pathogenesis of cardiometabolic disease in HIV disease.

HDL-cholesterol in coronary artery disease risk: function or structure?

High-density lipoproteins (HDL) are inversely related with coronary artery disease (CAD) and HDL-cholesterol is the only standardized and reproducible parameter available to estimate plasma concentration of these lipoproteins. However, pharmacological interventions intended to increase HDL-cholesterol have not been consistently associated to an effective CAD risk reduction. Among patients with a myocardial infarction, 43 and 44% of men and women, respectively, had normal plasma levels of HDL-cholesterol, whereas genetic studies have failed to show a causal association between HDL-cholesterol and CAD risk. Instead, HDL functionality seems to be the target to be evaluated, but the existing methods are still poorly reproducible and far to be adapted to the clinical laboratory. HDL subclasses rise as a potential alternative for the evaluation of CAD risk; HDL subclasses are a surrogate of intravascular metabolism of these lipoproteins and probably of their functionality. Low levels of large HDL and increased proportions of small particles are the most remarkable features associated to an increased risk of type 2 diabetes mellitus (T2DM) or CAD. However, inflammation and other environmental factors are related with abnormal HDL structure, and, as a consequence, more prospective studies are needed to better support the clinical usefulness of HDL subclasses. New insights from proteome and lipidome profiles of HDL will provide potential HDL-related biomarkers in the coming years.

Systematic review: Evaluating the effect of lipid-lowering therapy on lipoprotein and lipid values

PURPOSE

This systematic review was performed to summarize published experience using low density lipoprotein particle number (LDL-P) to monitor the efficacy of lipid-lowering pharmacotherapies.

METHODS

Studies were identified from a literature search of MEDLINE (January 1, 2000 - June 30, 2012); and abstract searches of select conferences. All accepted studies reported mean (or median) nuclear magnetic resonance (NMR)-based LDL-P values for at least 10 subjects receiving lipid lowering pharmacotherapy.

RESULTS

Searches revealed 36 studies (with 61 treatment arms) in which LDL-P measurements were reported pre- and post-treatment. Most studies also reported changes in low-density lipoprotein cholesterol (LDL-C), but fewer studies reported changes in apolipoprotein B (apoB)(n = 20) and non-HDL-C (n = 28). Treatments included statins (22 arms/15 studies), fibrates (7 arms/7 studies), niacin (7 arms/6 studies), bile acid sequestrants (5 arms/2 studies), an anti-apoB oligonucleotide (2 arms/2 studies), combination therapies (8 arms/6 studies), anti-diabetics (5 arms/4 studies), and, other treatments (5 arms/2 studies). Lipid-lowering pharmacotherapy resulted in reductions in mean LDL-P in all but two studies. In several statin studies, the percent reductions in LDL-P were smaller than reductions in LDL-C, comparable changes were reported when LDL-P and apoB, were reported.

CONCLUSIONS

Study-level data from this systemic review establish that different lipid lowering agents can lead to discordance between LDL-P and LDL-C, therefore, basing LDL-lowering therapy only on the achievement of cholesterol goals may result in a treatment gap. Therefore, the use of LDL-P for monitoring lipid-lowering therapy, particularly for statins, can provide a more accurate assessment of residual cardiovascular risk.

Lipoprotein subfractions in metabolic syndrome and obesity: clinical significance and therapeutic approaches

Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk.

Lipoprotein subfractions in metabolic syndrome and obesity: clinical significance and therapeutic approaches

Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk.

Lipid lowering efficacy of atorvastatin

BACKGROUND

Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

To quantify the dose-related effects of atorvastatin on blood lipids and withdrawals due to adverse effects (WDAE).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library Issue 4, 2011, MEDLINE (1966 to November 2011), EMBASE (1980 to November 2011), ISI Web of Science (1899 to November 2011) and BIOSIS Previews (1969 to November 2011). No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of 3 to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. WDAE information was collected from the placebo-controlled trials.

MAIN RESULTS

Two hundred fifty-four trials evaluated the dose-related efficacy of atorvastatin in 33,505 participants. Log dose-response data revealed linear dose-related effects on blood total cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides. Combining all the trials using the generic inverse variance fixed-effect model for doses of 10 to 80 mg/day resulted in decreases of 36% to 53% for LDL-cholesterol. There was no significant dose-related effects of atorvastatin on blood high-density lipoprotein (HDL)-cholesterol. WDAE were not statistically different between atorvastatin and placebo for these short-term trials (risk ratio 0.99; 95% confidence interval 0.68 to 1.45).

AUTHORS' CONCLUSIONS

Blood total cholesterol, LDL-cholesterol and triglyceride lowering effect of atorvastatin was dependent on dose. Log dose-response data was linear over the commonly prescribed dose range. Manufacturer-recommended atorvastatin doses of 10 to 80 mg/day resulted in 36% to 53% decreases of LDL-cholesterol. The review did not provide a good estimate of the incidence of harms associated with atorvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 37% of the placebo-controlled trials.

Rosuvastatin does not affect human apolipoprotein A-I expression in genetically modified mice: a clue to the disputed effect of statins on HDL

BACKGROUND AND PURPOSE

Besides a significant reduction of low-density lipoprotein (LDL) cholesterol, statins moderately increase high-density lipoprotein (HDL) levels. In vitro studies have indicated that this effect may be the result of an increased expression of apolipoprotein (apo)A-I, the main protein component of HDL. The aim of the present study was to investigate in vivo the effect of rosuvastatin on apoA-I expression and secretion in a transgenic mouse model for human apoA-I.

EXPERIMENTAL APPROACH

Human apoA-I transgenic mice were treated for 28 days with 5, 10 or 20 mg·kg(-1) ·day(-1) of rosuvastatin, the most effective statin in raising HDL levels. Possible changes of apoA-I expression by treatment were investigated by quantitative real-time RT-PCR on RNA extracted from mouse livers. The human apoA-I secretion rate was determined in primary hepatocytes isolated from transgenic mice from each group after treatment.

KEY RESULTS

Rosuvastatin treatment with 5 and 10 mg·kg(-1) ·day(-1) did not affect apoA-I plasma levels, whereas a significant decrease was observed in mice treated with 20 mg·kg(-1) ·day(-1) of rosuvastatin (-16%, P < 0.01). Neither relative hepatic mRNA concentrations of apoA-I nor apoA-I secretion rates from primary hepatocytes were influenced by rosuvastatin treatment at each tested dose.

CONCLUSIONS AND IMPLICATIONS

In human apoA-I transgenic mice, rosuvastatin treatment does not increase either apoA-I transcription and hepatic secretion, or apoA-I plasma levels. These results support the hypothesis that other mechanisms may account for the observed HDL increase induced by statin therapy in humans.

Randomised study of ezetimibe, start doses of original statins, and their combination in patients with coronary heart disease and hyperlipidemia Part 2. Therapy effects on the levels of C-reactive protein and proinflammatory cytokines

Aim. To assess the effects of original statins as monotherapy or in combination with ezetimibe on the levels of proinflammatory cytokines and high-sensitive C-reactive protein (hsCRP) in patients with coronary heart disease (CHD) and hyperlipidemia (HLP). Material and methods. The study included 60 male and female patients with CHD, primary polygenic HLP, and the levels of low-density lipoprotein cholesterol (LDL-CH) of 2,9-4,9 mmol/l. Monotherapy with original statins or ezetimibe lasted for 6 months, while the combination therapy lasted for 3 months. In all randomised patients, the levels of hsCRP, interleukin 6 (IL-6), and monocyte chemotactic protein-1 (MCP-1) were measured at baseline, 12 and 24 weeks after the therapy started. Results. At baseline, median hsCRP levels in the groups of Ezetrol, Zocor, Liprimar, and Crestor monotherapy were 0,5-0,88 mg/l, with no significant dynamics after 3 months of the treatment. Baseline IL-6 levels across the monotherapy groups were 1,94-2,54 pg/ml; at 3 months, there was a non-significant reduction by 7-32 %. After 3 months of the therapy, the decrease in MCP-1 levels was not statistically significant (-1,3-7,7 %). The combined therapy did not result in a significant dynamics of hsCRP concentrations, with the exception of the group receiving Ezetrol and Liprimar. Although the combined therapy further reduced MCP-1 levels (by 30-78 pg/ml), these changes were not statistically significant. No significant difference was observed across statin and Ezetrol groups in terms of their effects on IL-6 and MCP-1 levels. Conclusion. The comparison of the three treatment schemes demonstrated similar, but not statistically significant reduction on the levels of hsCRP, IL-6, and MCP-1. No marked benefits were observed for either monotherapy or combination therapy over 12-24 weeks of the follow-up.

Up-regulation of hepatic low-density lipoprotein receptor-related protein 1: a possible novel mechanism of antiatherogenic activity of hydroxymethylglutaryl-coenzyme A reductase inhibitor Atorvastatin and hepatic LRP1 expression

Low-density lipoprotein receptor-related protein 1 (LRP1) binds to apolipoprotein E and serves as a receptor for remnant lipoproteins in the liver, thus playing an important role in clearing these atherogenic particles. In this study, we investigated the effect of atorvastatin, a hydroxymethylglutaryl-coenzyme A reductase inhibitor, on hepatic LRP1 expression. We used HepG2 and Hep3B cells for in vitro study, and Otsuka Long-Evans Tokushima fatty and Sprague-Dawley rats for in vivo study. We used relatively high pharmacologic dose of atorvastatin in this study (in vitro, 0.5 μmol/L in culture media, for 48 hours; in vivo, 20 mg/[kg d], for 6 weeks). Atorvastatin increased LRP1 and low-density lipoprotein (LDL) receptor expression in HepG2 and Hep3B cells and induced hepatic LRP1 and LDL receptor expression in chow diet-fed Sprague-Dawley rats and high-fat diet-fed Otsuka Long-Evans Tokushima fatty rats. Atorvastatin decreased intracellular sterol level and increased the amount of the nuclear form of sterol response element-binding protein-2 (SREBP-2) in both HepG2 and Hep3B cells as well as in two animal models. Treatment of HepG2 cells with LDL increased intracellular sterol level and reduced LRP1, LDL receptor, and SREBP-2. When SREBP-2 in HepG2 cells was knocked down by small interfering RNA, the induction of LRP1 expression by atorvastatin did not take place. In conclusion, up-regulation of hepatic LRP1 might be a novel mechanism by which statin treatment decreases remnant lipoproteins. In addition, SREBP-2 acts as a mediator of atorvastatin-induced up-regulation of hepatic LRP1. Future studies using standard doses of atorvastatin in humans are needed to elucidate clinical relevance of these findings.

Dyslipidaemia of obesity, metabolic syndrome and type 2 diabetes mellitus: the case for residual risk reduction after statin treatment

Dyslipidaemia is frequently present in obesity, metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM). The predominant features of dyslipidaemia in these disorders include increased flux of free fatty acids (FFA), raised triglyceride (TG) and low high density lipoprotein cholesterol (HDL-C) levels, a predominance of small, dense (atherogenic) low density lipoprotein cholesterol (LDL) particles and raised apolipoprotein (apo) B values Posprandial hyperlipidaemia may also be present. Insulin resistance (IR) appears to play an important role in the pathogenesis of dyslipidaemia in obesity, MetS and T2DM. The cornerstone of treatment of this IR-related dyslipidaemia is lifestyle changes and in diabetic patients, tight glycaemic control. In addition to these measures, recent clinical trials showed benefit with statin treatment. Nevertheless, a substantial percentage of patients treated with statins still experience vascular events. This residual vascular risk needs to be addressed. This review summarizes the effects of hypolipidaemic drug combinations (including statins with cholesterol ester protein inhibitors, niacin, fibrates or fish oil, as well as fibrate-ezetimibe combination) on the residual vascular risk in patients with obesity, MetS or T2DM.

The differential effects of EPA and DHA on cardiovascular risk factors

Compelling evidence exists for the cardioprotective benefits resulting from consumption of fatty acids from fish oils, EPA (20:5n-3) and DHA (22:6n-3). EPA and DHA alter membrane fluidity, interact with transcription factors such as PPAR and sterol regulatory element binding protein, and are substrates for enzymes including cyclooxygenase, lipoxygenase and cytochrome P450. As a result, fish oils may improve cardiovascular health by altering lipid metabolism, inducing haemodynamic changes, decreasing arrhythmias, modulating platelet function, improving endothelial function and inhibiting inflammatory pathways. The independent effects of EPA and DHA are poorly understood. While both EPA and DHA decrease TAG levels, only DHA appears to increase HDL and LDL particle size. Evidence to date suggests that DHA is more efficient in decreasing blood pressure, heart rate and platelet aggregation compared to EPA. Fish oil consumption appears to improve arterial compliance and endothelial function; it is not yet clear as to whether differences exist between EPA and DHA in their vascular effects. In contrast, the beneficial effect of fish oils on inflammation and insulin sensitivity observed in vitro and in animal studies has not been confirmed in human subjects. Further investigation to clarify the relative effects of consuming EPA and DHA at a range of doses would enable elaboration of current understanding regarding cardioprotective effects of consuming oily fish and algal sources of long chain n-3 PUFA, and provide clearer evidence for the clinical therapeutic potential of consuming either EPA or DHA-rich oils.

Short-term treatment with high-dose atorvastatin reduces LDL cholesterol but shows no anti-inflammatory effects in normolipidemic subjects with normal CRP levels

The benefit in reducing cardiovascular risk with statins has been attributed both to cholesterol lowering and pleiotropic effects. These pleiotropic effects are thought to include attenuation of the inflammatory response due to reduced prenylation of proteins in the inflammatory cascade. We conducted studies in normolipidemic subjects to determine if treatment with high-dose (80 mg) atorvastatin could reduce circulating levels of inflammatory markers. We also determined whether high-dose atorvastatin affected the inflammatory response of monocytes stimulated with lipopolysaccharide (LPS) ex vivo. We found that treatment with atorvastatin rapidly and significantly reduced plasma low-density lipoprotein (LDL) cholesterol levels in subjects treated for 2 weeks. However, statin treatment had no discernible effect on plasma levels of the inflammatory markers high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor (TNF)-alpha, or interleukin (IL-6) and no effect on the cytokine response of monocytes following ex vivo stimulation with LPS. High-dose atorvastatin treatment of normolipidemic subjects with normal C-reactive protein levels has no effect on the inflammatory response assessed by monocyte stimulation with LPS ex vivo despite significant reductions in LDL cholesterol levels.

Are post-treatment low-density lipoprotein subclass pattern analyses potentially misleading?

BACKGROUND

Some patients administered cholesterol-lowering therapies may experience an increase in the proportion of small LDL particles, which may be misinterpreted as a worsening of atherosclerotic coronary heart disease risk. This study assessed the lipid effects of adding ezetimibe to atorvastatin or doubling the atorvastatin dose on low-density lipoprotein cholesterol (LDL-C) levels (and the cholesterol content of LDL subclasses), LDL particle number (approximated by apolipoprotein B), and LDL particle size. This was a multicenter, double-blind, randomized, parallel-group study of hypercholesterolemic, high atherosclerotic coronary heart disease risk patients. After stabilization of atorvastatin 40 mg, 579 patients with LDL-C >70 mg/dL were randomized to 6 weeks of ezetimibe + atorvastatin 40 mg or atorvastatin 80 mg. Efficacy parameters included changes from baseline in LDL-C, apolipoprotein B, non-high-density lipoprotein cholesterol (non-HDL-C), and lipoprotein subclasses (Vertical Auto Profile II) and pattern for the overall population, as well as patient subgroups with baseline triglyceride levels <150 mg/dL or ≥150 mg/dL.

RESULTS

Both treatments significantly reduced LDL-C (and the cholesterol content of most LDL subfractions [LDL1-4]) apolipoprotein B, non-HDL-C levels, but did not reduce the proportion of smaller, more dense LDL particles; in fact, the proportion of Pattern B was numerically increased. Results were generally similar in patients with triglyceride levels <150 or ≥150 mg/dL.

CONCLUSIONS

When assessing the effects of escalating cholesterol-lowering therapy, effects upon Pattern B alone to assess coronary heart disease risk may be misleading when interpreted without considerations of other lipid effects, such as reductions in LDL-C, atherogenic lipoprotein particle concentration, and non-HDL-C levels.

TRIAL REGISTRATION

(Registered at clinicaltrials.gov: Clinical trial # NCT00276484).