The effects of low-dose simvastatin and ezetimibe compared to high-dose simvastatin alone on post-fat load endothelial function in patients with metabolic syndrome: a randomized double-blind crossover trial

The Pleiotropic Effects of Lipid-Modifying Interventions: Exploring Traditional and Emerging Hypolipidemic Therapies

Atherosclerotic cardiovascular disease poses a significant global health issue, with dyslipidemia standing out as a major risk factor. In recent decades, lipid-lowering therapies have evolved significantly, with statins emerging as the cornerstone treatment. These interventions play a crucial role in both primary and secondary prevention by effectively reducing cardiovascular risk through lipid profile enhancements. Beyond their primary lipid-lowering effects, extensive research indicates that these therapies exhibit pleiotropic actions, offering additional health benefits. These include anti-inflammatory properties, improvements in vascular health and glucose metabolism, and potential implications in cancer management. While statins and ezetimibe have been extensively studied, newer lipid-lowering agents also demonstrate similar pleiotropic effects, even in the absence of direct cardiovascular benefits. This narrative review explores the diverse pleiotropic properties of lipid-modifying therapies, emphasizing their non-lipid effects that contribute to reducing cardiovascular burden and exploring emerging benefits for non-cardiovascular conditions. Mechanistic insights into these actions are discussed alongside their potential therapeutic implications.

Comparative Safety and Efficacy of Low/Moderate-Intensity Statin plus Ezetimibe Combination Therapy vs. High-Intensity Statin Monotherapy in Patients with Atherosclerotic Cardiovascular Disease: An Updated Meta-Analysis

AIM

Statin therapy is considered the gold standard for treating hypercholesterolemia. This updated meta-analysis aims to compare the efficacy and safety of a low/moderate-intensity statin in combination with ezetimibe compared with high-intensity statin monotherapy in patients with atherosclerotic cardiovascular disease (ASCVD).

METHODS

A systematic search of two databases (PubMed and Cochrane CENTRAL) was conducted from inception to January 2023 and a total of 21 randomized clinical trials (RCTs) were identified and included in the analysis. Data were pooled using Hedges's g and a Mantel-Haenszel random-effects model to derive standard mean differences (SMDs) and 95% confidence intervals (Cis). The primary outcome studied was the effect of these treatments on lipid parameters and safety events.

RESULTS

The results revealed that combination therapy was more effective in reducing low-density lipoprotein cholesterol (LDL-C) levels (SMD= - 0.41; CI - 0.63 to - 0.19; P = 0.0002). There was no significant change in the levels of high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP), Apo A1, or Apo B. The safety of these treatments was assessed by the following markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatine phosphokinase (CK), and a significant difference was only observed in CK (SMD: - 0.81; CI - 1.52 to - 0.10; P = 0.02).

CONCLUSION

This meta-analysis demonstrated that the use of low/moderate-intensity statin combination therapy significantly reduced LDL-C levels compared with high-intensity statin monotherapy, making it preferable for patients with related risks. However, further trials are encouraged to evaluate potential adverse effects associated with combined therapy.

Effectiveness of statins vs. exercise on reducing postprandial hypertriglyceridemia in dyslipidemic population: A systematic review and network meta-analysis

BACKGROUND

Individuals at risk of suffering cardiovascular disease (CVD) present with larger increases in blood triglyceride (TG) concentration after a high-fat meal than do healthy individuals. These postprandial hypertriglyceride levels are an independent risk factor for CVD. Prescription of statins and a bout of prolonged exercise are both effective in lowering postprandial hypertriglyceride levels. We aimed to evaluate the comparative effectiveness of statins vs. a bout of aerobic exercise in reducing fasting and postprandial TG (PPTG) concentrations in individuals at high risk of developing CVD.

METHODS

Thirty-seven studies from a systematic literature search of the PubMed, EMBASE, and Cochrane databases were included in this review. The selected studies conducted trials involving statin therapy (n = 20) or a bout of aerobic exercise (n = 19) and measured their impact on PPTG levels as the outcome. Two studies analyzed both treatments and were included in duplicate. The meta-analysis was constructed using a random-effects model to calculate the mean difference (MD). The Student t test was used to compare the data sets for statins vs. exercise.

RESULTS

Overall, statin and exercise interventions showed similar reductions in PPTG levels, with an MD of -0.65 mmol/L for statins (95% confidence interval (95%CI): -0.54 to -0.77; p < 0.001) and -0.46 mmol/L for exercise (95%CI: -0.21 to -0.71; p < 0.01). However, statins lowered fasting TG levels more than exercise (MD = -1.54 mmol/L, 95%CI: -2.25 to -0.83; p = 0.009).

CONCLUSION

Although aerobic exercise is effective in lowering blood TG levels, statins seem to be more efficient, especially in the fasted state. A combination of exercise and statins might reveal a valuable approach to the treatment and prevention of CVD. More studies are required to determine the underlying mechanisms and the possible additive effects of these interventions.

Comparative safety and efficacy of low- or moderate-intensity statin plus ezetimibe combination therapy and high-intensity statin monotherapy: A meta-analysis of randomized controlled studies

Statin is highly recommended for dyslipidemia to prevent atherosclerosis-related cardiovascular diseases and death. The aim of this study was to compare the efficacies and safeties of low/moderate-intensity statin plus ezetimibe combination therapy vs. high-intensity statin monotherapy. Meta-analysis was conducted on data included in published studies performed to compare the effects of the two treatments on lipid parameters and hs-CRP. Safety-related parameters were also evaluated. Eighteen articles were included in the meta-analysis. In terms of efficacy, low/moderate-intensity statin plus ezetimibe reduced LDL-C (SE = 0.307; 95% CI 0.153–0.463), TC (SE = 0.217; 95% CI 0.098–0.337), triglyceride (SE = 0.307; 95% CI 0.153–0.463), and hs-CRP (SE = 0.190; 95% CI 0.018–0.362) significantly more than high-intensity statin therapy. In terms of safety, the two treatments were not significantly different in terms of ALT elevation, but high-intensity statin increased AST and CK significantly more than combination therapy. This analysis indicates that low/moderate-intensity statin plus ezetimibe combined therapy is more effective and safer than high-intensity statin monotherapy, which suggests the addition of ezetimibe to statin should be preferred over increasing statin dose and that high-intensity statin should be used more carefully, especially in patients with related risks.

Impact of decreased insulin resistance by ezetimibe on postprandial lipid profiles and endothelial functions in obese, non-diabetic-metabolic syndrome patients with coronary artery disease

The association between insulin resistance and lipid dysmetabolism after consuming a meal is unclear. We aimed at assessing the effects of ezetimibe on postprandial hyperlipidemia and hyperinsulinemia and to find out whether the medication improves endothelial function in obese metabolic syndrome (MetS) patients with coronary artery disease (CAD). We obtained oral fat loading test results (4 and 6 h after load) and brachial flow-mediated vasodilation (FMD) measurements before and 24 weeks after ezetimibe treatment initiation from 27 MetS patients with CAD and from 68 control patients with CAD alone. Serum triglyceride (TG) and insulin levels (2 h after the loading dose) were significantly higher in MetS patients than in control patients. The incremental areas under the curve (iAUCs) for these levels decreased significantly after ezetimibe treatment in MetS patients but not in control patients. Treatment with ezetimibe resulted in significant FMD changes in MetS patients (from 3.4 to 4.9%, P = 0.002), but not in control patients (from 5.1 to 5.4%, P = 0.216). When MetS patients were divided into two groups based on the median insulin iAUC reduction rate (higher group ≥ 34%, n = 14; lower group < 34%, n = 13), those in the higher group showed a significantly higher rate of change in the iAUCs of TG and FMD than those in the lower group (TG, 31.0% vs. 10.8%; P = 0.033; FMD, 39.2% vs. 9.8%; P = 0.037). These results suggest that ezetimibe may reverse insulin resistance, reducing lipid dysmetabolism after a meal and endothelial dysfunction in MetS patients with CAD.

Lipid lowering drugs and inflammatory changes: an impact on cardiovascular outcomes?

Inflammatory changes are responsible for maintenance of the atherosclerotic process and may underlie some of the most feared vascular complications. Among the multiple mechanisms of inflammation, the arterial deposition of lipids and particularly of cholesterol crystals is the one responsible for the activation of inflammasome NLRP3, followed by the rise of circulating markers, mainly C-reactive protein (CRP). Elevation of lipoproteins, LDL but also VLDL and remnants, associates with increased inflammatory changes and coronary risk. Lipid lowering medications can reduce cholesterolemia and CRP: patients with elevations of both are at greatest cardiovascular (CV) risk and receive maximum benefit from therapy. Evaluation of the major drug series indicates that statins exert the largest LDL and CRP reduction, accompanied by reduced CV events. Other drugs, mainly active on the triglyceride/HDL axis, for example, PPAR agonists, may improve CRP and the lipid pattern, especially in patients with metabolic syndrome. PCSK9 antagonists, the newest most potent medications, do not induce significant changes in inflammatory markers, but patients with the highest baseline CRP levels show the best CV risk reduction. Parallel evaluation of lipids and inflammatory changes clearly indicates a significant link, both guiding to patients at highest risk, and to the best pharmacological approach. Key messages Lipid lowering agents with "pleiotropic" effects provide a more effective approach to CV prevention In CANTOS study, patients achieving on-treatment hsCRP concentrations ≤2 mg/L had a higher benefit in terms of reduction in major CV events The anti-inflammatory activity of PCSK9 antagonists appears to be of a minimal extent.

Omega-3 fatty acids improve postprandial lipemia and associated endothelial dysfunction in healthy individuals - a randomized cross-over trial

BACKGROUND

Postprandial elevation of triglycerides impairs endothelial function and contributes to the development of atherosclerosis. We investigated the effects of omega-3 fatty acids on postprandial endothelial function and lipid profiles.

METHODS

Healthy volunteers [10] were given supplementation at 4g/day omega-3 fatty acids (or were not treated) for 4 weeks in a randomised crossover study. Postprandial levels of various lipids were monitored and endothelial function assessed by brachial artery flow-mediated dilation during fasting and after a standard cookie test.

RESULTS

Omega-3 fatty acids reduced postprandial endothelial dysfunction compared with the control diet (flow-mediated dilation at 4h=-0.5±1.2 vs. -2.0±1.6%, P=0.03). Postprandial levels of triglycerides, apolipoprotein B-48, and remnant lipoprotein-cholesterol increased in untreated subjects, peaked at 2-4h, and returned to baseline at 8h, whereas low-density lipoprotein-cholesterol levels did not change. Supplementation with omega-3 fatty acids significantly suppressed postprandial elevation of triglycerides (incremental area under the curve=220±209 vs. 374±216mg/h/dL, P=0.04) and remnant lipoprotein-cholesterol (incremental area under the curve=21.7±13.8 vs. 13.3±12.9mg/h/dL, P=0.04). Supplementation with omega-3 fatty acids significantly suppressed the increase in triglyceride content in chylomicrons as well as in very-low-density lipoproteins from baseline to 4h after the cookie test.

CONCLUSION

Omega-3 fatty acids significantly decreased postprandial triglyceride elevation and postprandial endothelial dysfunction, suggesting that omega-3 fatty acids may have vascular protective effects in postprandial state.

Bezafibrate improves postprandial hypertriglyceridemia and associated endothelial dysfunction in patients with metabolic syndrome: a randomized crossover study

Background

Postprandial elevation of triglyceride-rich lipoproteins impairs endothelial function, which can initiate atherosclerosis. We investigated the effects of bezafibrate on postprandial endothelial dysfunction and lipid profiles in patients with metabolic syndrome.

Methods

Ten patients with metabolic syndrome were treated with 400 mg/day bezafibrate or untreated for 4 weeks in a randomized crossover study. Brachial artery flow-mediated dilation (FMD) and lipid profiles were assessed during fasting and after consumption of a standardized snack. Serum triglyceride and cholesterol contents of lipoprotein fractions were analyzed by high-performance liquid chromatography.

Results

Postprandial FMD decreased significantly and reached its lowest value 4 h after the cookie test in both the bezafibrate and control groups, but the relative change in FMD from baseline to minimum in the bezafibrate group was significantly smaller than that in the control group (-29.0 ± 5.9 vs. -42.9 ± 6.2 %, p = 0.04). Bezafibrate significantly suppressed postprandial elevation of triglyceride (incremental area under the curve (AUC): 544 ± 65 vs. 1158 ± 283 mg h/dl, p = 0.02) and remnant lipoprotein cholesterol (incremental AUC: 27.9 ± 3.5 vs. 72.3 ± 14.1 mg h/dl, p < 0.01). High-performance liquid chromatography analysis revealed that postprandial triglyceride content of the chylomicron and very low-density lipoprotein fractions was significantly lower in the bezafibrate group than in the control group (p < 0.05).

Conclusion

Bezafibrate significantly decreased postprandial endothelial dysfunction, and elevations of both exogenous and endogenous triglycerides in patients with metabolic syndrome, suggesting that bezafibrate may have vascular protective effects in these patients.

Clinical trial registration

Unique Identifiers: UMIN000012557

The efficacy of Ezetimibe added to ongoing Fibrate-Statin therapy on postprandial lipid profile in the patients with type 2 Diabetes mellitus

BACKGROUND

Postprandial hypertriglyceridemia in diabetes mellitus can be followed by endothelial dysfunction, impaired vascular compliance and increased cardiovascular complications. So focus on better control of postprandial hypertriglyceridemia is as important as controlling fasting triglyceride level in type 2 DM.

OBJECTIVE

We evaluated the effect of ezetimibe adding to fibrate or statin on postprandial hypertriglyceridemia.

METHODS

In a randomized controlled clinical trial, 47 subjects with type 2 diabetes and hypertiglyceridemia were enrolled and divided in three treatment groups including Gemfibrozil 1200mg/d + placebo(group A), Ezetimibe10mg/d + Gemfibrozile 1200mg/d(group B) or Ezetimibe10mg/d + Atorvastatin10mg/d (group C) for a 6- week period. Oral fat loading test were performed in the initiation and also at the end of the study and lipid profile and APOB were measured.

RESULTS

Fasting and postprandial serum triglyceride (TG) decreased significantly with all the three treatment groups with no difference between them in the percent of TG reduction. Although serum total cholesterol decreased significantly in all the three groups of treatment its reduction was more prominent in group C(-38.1% ± 11.2%in group C vs. -16.5% ± 19.6% and -7.2% ± 10.7% in groups B & A respectively, p < 0.0001 ). Fasting serum HDL increased significantly only by Gemfibrozil (23.4% ± 28.4% vs. 6.4% ± 18.9% and 1.8% ± 17.7%, p < 0.05 ). Fasting serum APOB was reduced only in ezetimibe containing groups (B &C).

CONCLUSION

Adding ezetimibe to gemfibrozil has no additional effect on reducing postprandial TG but ezetimibe can potentiate the effect of low-dose atorvastatin on lowering TG and LDL-c.

High-dose statin monotherapy versus low-dose statin/ezetimibe combination on fasting and postprandial lipids and endothelial function in obese patients with the metabolic syndrome: The PANACEA study

BACKGROUND

Low-dose statin therapy in combination with ezetimibe, an inhibitor of intestinal cholesterol absorption, lowers plasma LDL-cholesterol levels to a similar degree as high-dose statin monotherapy. This study assessed whether similar LDL-cholesterol lowering with simvastatin/ezetimibe combination therapy improves fasting and postprandial arterial endothelial function compared to high-dose statin therapy alone.

METHODS

Multicenter, double-blind, crossover trial in 100 abdominally obese patients with the metabolic syndrome, randomized to 6 weeks' treatment with simvastatin 80 mg or simvastatin/ezetimibe 10/10 mg. Flow mediated dilatation (FMD) and peripheral arterial tonometry (EndoPAT) as well as plasma lipids were measured in the fasting state and after an oral lipid load at baseline and after both treatments.

RESULTS

Fasting LDL-cholesterol levels (3.57 mmol/L at baseline) were reduced to 1.79 mmol/L following treatment with simvastatin 80 mg and 1.81 mmol/L with simvastatin/ezetimibe 10/10 mg, respectively. Plasma lipids were similar at 4 h after an oral lipid load following both treatments for 6 weeks. Fasting endothelial function was also similar with both treatments when assessed by FMD (adjusted mean ± SE: 4.35 ± 0.19 vs. 4.43 ± 0.18; P = 0.777) and EndoPAT (2.12 ± 0.05 vs 2.20 ± 0.05; P = 0.304). After an oral fat load, changes in endothelial function were also comparable for both treatments as assessed by FMD (-0.34 ± 0.21 vs. -0.43 ± 0.20; P = 0.766) and EndoPAT (0.00 ± 0.07 vs. -0.04 ± 0.08; P = 0.712).

CONCLUSION

Treatment with simvastatin/ezetimibe 10/10 mg induced no difference in endothelial function in the fasting and postprandial state compared to simvastatin 80 mg while attaining similar LDL-c levels in obese patients with metabolic syndrome.

Effect of High-Dose Statin Versus Low-Dose Statin Plus Ezetimibe on Endothelial Function

Background:

Combining low-dose statin and ezetimibe reduces the low-density lipoprotein cholesterol (LDL-C) similar to high-dose statin. However, whether there is a difference in the effect of these 2 lipid-lowering regimes on endothelial function is still controversial.

Methods:

We performed a systematic search of databases (MEDLINE [1950 to September 2011], EMBASE [1966 to September 2011]) and references of identified studies. Completely published randomized controlled trials comparing the effect of high-dose statin with low-dose stain plus ezetimibe on endothelial function (flow-mediated dilation [FMD] method) were included in this study.

Results:

Six trials with a total of 213 participants were included in the meta-analysis. The pooled weighted mean difference of FMD did not differ between the 2 lipid-lowering regimes (0.22%; 95% confidence interval [CI]: −0.85%-1.29%, P = .68). Furthermore, no significant reduction in LDL-C and C-reactive protein (CRP) occurred with high-dose statin versus low-dose statin plus ezetimibe (pooled weighted mean differences of LDL-C and CRP were −4.12 mg/dL, 95% CI: −9.54-1.12 mg/dL, P = .12, and −0.02 mg/L, 95% CI: −0.31-0.27 mg/L, P = .89, respectively).

Conclusions:

Based on the currently available evidence, combining a low-dose statin with ezetimibe may provide similar beneficial effects on endothelial function as high-dose statin.

Intestinal sterol transporters and cholesterol absorption inhibition

PURPOSE OF REVIEW

Statin therapy is the mainstay of lipid-lowering therapy; however, many patients, particularly those at high risk, do not achieve sufficient LDL-cholesterol (LDL-C) lowering. Thus, there remains an unmet medical need for more effective and well tolerated lipid-lowering agents. Guidelines recommend combining additional lipid-lowering agents with a complementary mode of action for these patients. One approach to complementing statin therapy is combination with inhibitors that block the intestinal absorption of dietary and biliary cholesterol. This review summarizes what is currently known about intestinal sterol transporters and cholesterol absorption inhibitors (CAIs).

RECENT FINDINGS

The only lipid-lowering agent currently available that specifically targets an intestinal sterol transporter (Niemann-Pick C1-like 1) is the CAI, ezetimibe. It is effective in lowering LDL-C, both when given alone and when combined with a statin. Clinical outcome data with ezetimibe combined with simvastatin have recently become available, and definitive evidence that the incremental LDL-C lowering attributable to the ezetimibe component reduces cardiovascular events beyond simvastatin alone is currently under study. Other novel CAIs have been evaluated based upon the structure and properties of ezetimibe, but none remain in development.

SUMMARY

Additional lipid-lowering agents are needed to fulfill an unmet medical need for those patients who do not achieve optimal LDL-C goals on statin monotherapy. The inhibition of cholesterol absorption is an important therapeutic strategy to reduce cholesterol levels. Based upon the demonstrated lipid-altering efficacy and safety of ezetimibe, several CAIs have been identified; all to date have been discontinued due to limited efficacy.

Impact of hypertriglyceridemia on endothelial dysfunction during statin ± ezetimibe therapy in patients with coronary heart disease

Despite the use of statin therapy and achieving the target for low-density lipoprotein cholesterol, a substantial number of coronary events are not prevented, and residual risk factors remain unsettled. Recently, ezetimibe has been shown to reduce not only low-density lipoprotein cholesterol but also triglyceride (TG) levels. The aim of this study was to investigate the associations of residual risk factors, mainly hypertriglyceridemia, with endothelial function during statin therapy in patients with coronary heart disease and examine the effect of ezetimibe add-on therapy. A total of 109 consecutive patients with coronary heart disease during statin therapy were enrolled. Lipid profile was measured and endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery in a fasting state. Next, 32 patients with high TG levels (≥150 mg/dl) were prospectively assigned to the ezetimibe add-on group or the no-ezetimibe group, and endothelial function was assessed after 3 months. Multivariate linear regression analysis demonstrated that serum TG and high-density lipoprotein cholesterol levels were independent determinants of percentage FMD (β = -0.210 and 0.208, respectively, p <0.05). In patients with high TG levels, ezetimibe add-on therapy significantly improved percentage FMD (from 3.3 ± 1.1% to 4.0 ± 1.1%, p <0.005), whereas no significant change was observed in the no-ezetimibe group. Moreover, the improvement in percentage FMD was significantly associated with reduction in serum TG levels (β = -0.387, p <0.05) independent of the change in serum low-density lipoprotein cholesterol levels. In conclusion, hypertriglyceridemia is independently associated with endothelial dysfunction in patients with coronary heart disease during statin therapy. Ezetimibe add-on therapy improves endothelial function in these high-risk populations.

Ezetimibe improves postprandial hyperlipemia and its induced endothelial dysfunction

OBJECTIVE

Postprandial hyperlipemia has been shown to impair endothelial function and contribute to the development of atherosclerosis. We investigated the association between postprandial lipid profiles and endothelial function, and we examined the effects of ezetimibe on postprandial hyperlipemia and lipemia-induced endothelial dysfunction.

METHODS

A randomized prospective trial in which 10 mg/day of ezetimibe was administered to 10 subjects for 4 weeks and not administered to 10 subjects (control group) was performed. Lipid profiles and endothelial function, assessed by brachial artery flow-mediated dilation (FMD) during a fasting state and at 2, 4, 6 and 8 h after an oral cookie loading test, were determined before and after treatment for 4 weeks.

RESULTS

In all subjects before treatment, the maximum reduction in postprandial %FMD was significantly correlated with the maximum increases in postprandial triglyceride (TG) (r=-0.499, P<0.05) and apolipoprotein B-48 (apoB-48) concentrations (r=-0.551, P<0.05). Ezetimibe treatment for 4 weeks significantly suppressed postprandial elevation in TG (area under the incremental curve, from 1419±594 to 968±32 1 mg h/dl, P<0.05), remnant lipoprotein cholesterol (from 66.9±27.6 to 38.9±15.4 mg h/dl, P<0.01) and apoB-48 (from 58.8±27.5 to 36.2±17.0 μg h/ml, P<0.05) concentrations, and postprandial endothelial dysfunction assessed by %FMD (maximum reduction in %FMD, from -2.6±1.1% to -1.2±0.8%, P<0.05), whereas no significant changes were observed in the control group.

CONCLUSION

Postprandial hyperlipemia is closely correlated with transient endothelial dysfunction. Ezetimibe improves postprandial hyperlipemia and its induced endothelial dysfunction.

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.

Differential effects of fluvastatin alone or in combination with ezetimibe on lipoprotein subfractions in patients at high risk of coronary events

BACKGROUND

Ezetimibe, a cholesterol-absorption inhibitor, significantly lowers low-density lipoprotein cholesterol (LDL-C) when administered in addition to statin treatment. The effect of ezetimibe on the incidence and progression of vascular disease is elusive. The objective of the study was to examine the effects of fluvastatin plus ezetimibe on lipoprotein subfractions in patients with type 2 diabetes and/or coronary heart disease.

MATERIALS AND METHODS

Ninety patients with LDL-C between 100 and 160 mg dL(-1) were enrolled in this prospective, randomized, single-blind, single-centre study. A total of 84 patients were treated with either fluvastatin 80 mg (n = 28) alone or in combination with ezetimibe 10 mg (n = 56) for 12 weeks to determine the effects on lipids, apolipoproteins and LDL subfractions by equilibrium density gradient ultracentrifugation. This study is registered with ClinicalTrials.gov, number NCT00814723.

RESULTS

Total cholesterol, LDL-C and apolipoprotein B were significantly more reduced in the combined therapy group. High density lipoproteins increased in the fluvastatin-only group and decreased in the combined therapy group. There was a significant difference between the two groups in buoyant and intermediate, but not in dense LDL particles.

CONCLUSIONS

Addition of ezetimibe to fluvastatin resulted in a further reduction of buoyant and intermediate, but not of dense LDL compared with fluvastatin alone.

Pleiotropic effects of ezetimibe: do they really exist?

Ezetimibe represents a new lipid lowering agent which inhibits cholesterol absorption. It effectively reduces low-density lipoprotein cholesterol when administered either alone or in combination with statins. However, its effect on cardiovascular mortality remains under question since it failed to demonstrate any significant changes in the primary endpoints of the recently published ENHANCE and SEAS studies. A possible explanation for this unsuccessful outcome is that ezetimibe lacks pleiotropic effects. This article aims to review the potential pleiotropic effects of the drug mainly on inflammation markers, lipoprotein subfractions and endothelial function.

The impact of ezetimibe on endothelial function and other markers of cardiovascular risk

OBJECTIVE

To review the published literature characterizing the impact of ezetimibe-containing lipid-lowering regimens on endothelial function and other markers of cardiovascular risk and discuss the potential relevance of these effects to the clinical benefit of ezetimibe.

DATA SOURCES

A MEDLINE search (2000-August 2009) was completed using the key words ezetimibe, statins, endothelial function, flow-mediated dilation, pleiotropic, and inflammation to identify relevant literature. Bibliographies of identified literature were reviewed for additional references.

STUDY SELECTION AND DATA EXTRACTION

All clinical studies published in English that evaluated the effect of ezetimibe on ancillary endpoints of cardiovascular disease risk, including endothelial function, inflammation, thrombosis, and oxidative stress, were evaluated.

DATA SYNTHESIS

Recent studies in patients with coronary artery disease (CAD), heart failure, and hypercholesterolemia have demonstrated that treatment with ezetimibe for 4-12 weeks elicits no improvement of endothelial function or other measures of cardiovascular disease risk. In contrast, other studies have reported that ezetimibe improves endothelial function in certain patient populations, including those with rheumatoid arthritis, CAD with type 2 diabetes, and metabolic syndrome. However, the statin monotherapy comparator groups in these studies that yielded equivalent reductions in cholesterol were superior, or at least equivalent to, ezetimibe-containing regimens in the improvement of these ancillary endpoints.

CONCLUSIONS

Overall, the evidence to date suggests that administration of ezetimibe, either as monotherapy or in combination with a statin, exerts minimal beneficial effects on endothelial function and other ancillary measures of cardiovascular disease risk beyond those conferred by its cholesterol-lowering effects. Studies with larger sample sizes and follow-up beyond 12 weeks remain necessary to further define the impact of ezetimibe on the processes integral to the pathogenesis and progression of cardiovascular disease.

Fluvastatin/fenofibrate vs. simvastatin/ezetimibe in patients with metabolic syndrome: different effects on LDL-profiles

BACKGROUND

Patients with metabolic syndrome (MS) and type 2 diabetes (T2DM) show increased risk for coronary artery disease. Lipoprotein metabolism is characterized by elevated triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) and predominance of atherogenic small, dense low-density lipoprotein (sdLDL), while low-density lipoprotein (LDL) cholesterol is only slightly elevated.

METHODS

Multicentre, randomized, open-label cross-over study investigating the effect of combination of fluvastatin/fenofibrate (80/200 mg) (F&F) on LDL-subfractions compared with combination of simvastatin/ezetimibe (20/10 mg) (S&E) in patients with MS/T2DM.

RESULTS

Seventy-five patients were randomized, 69 completed the study and LDL-subfractions of 56 patients were analysed. Thirty-eight out of 56 patients (68%) showed a profile dominated by sdLDL. In these, TG and total cholesterol (TC) were elevated compared with non-sdLDL patients. In all patients, reduction of TC and LDL cholesterol (LDL-C) by S&E was stronger than by F&F. The increase of HDL-C was stronger with S&E in the non-sdLDL group, whereas in the sdLDL group, there was no difference between treatments. In non-sdLDL patients, there was no effect on TG or LDL-radius. However, in the sdLDL group, F&F was more effective in reducing TG and increased LDL radius, whereas S&E reduced LDL radius even further.

CONCLUSIONS

S&E is more efficient in reducing TC and LDL-C. This is also true for HDL-C increase in non-sdLDL patients. However, in patients with sdLDL, F&F was more efficient in reducing TG and increasing LDL radius.