Intensive statin therapy in acute coronary syndromes: clinical benefits and vascular biology

Research trends in lipid-lowering therapies for coronary heart disease combined with hyperlipidemia: a bibliometric study and visual analysis

Background

Cardiovascular disease (CVD) poses a significant global health and economic challenge, with atherosclerosis being a primary cause. Over the past 40 years, substantial research has been conducted into the prevention and reversal of atherosclerosis, resulting in the development of lipid-lowering agents such as statins and fibrates. Despite the extensive literature and formulation of numerous therapeutic guidelines in this domain, a comprehensive bibliometric analysis of the current research landscape and trends has not been performed. This study aimed to elucidate the evolution and milestones of research into lipid-lowering treatments for coronary heart disease (CHD) in conjunction with hyperlipidemia through bibliometric analysis, offering insights into future directions for treatment strategies.

Methods

This study examined publications from 1986 to 2023 retrieved from the Web of Science database (Core Collection). Utilizing tools such as VOSviewer, Pajek, and CiteSpace, we analyzed publication and citation numbers, H-indexes, contributions by countries and institutions, authorship, journal sources, and keyword usage to uncover research trajectories and areas of focus.

Results

Our analysis of 587 publications revealed a recent surge in research output, particularly post-2003. The American Journal of Cardiology published the highest number of studies, with 40 articles, whereas Circulation received the highest number of citations (6,266). Key contributors included the United States, Japan, and China, with the United States leading in citation numbers and the H-index. Harvard University and Leiden University emerged as pivotal institutions, and Professors J. Wouter Jukema and Robert P. Giugliano were identified as leading experts. Keyword analysis disclosed five thematic clusters, indicating a shift in research towards new drug combinations and strategies, signaling future research directions.

Conclusion

The last 4 decades have seen a notable rise in publications on lipid-lowering therapies for CHD and hyperlipidemia, with the United States retaining world-leading status. The increase in international collaboration aids the shift towards research into innovative lipid-lowering agents and therapeutic approaches. PCSK9 inhibitors and innovative combination therapies, including antisense oligonucleotides and angiopoietin-like protein 3 inhibitors, provide avenues for future research, intending to maximize the safety and efficacy of treatment approaches.

Incremental Benefit of Lipid Lowering in a Large Chinese Population Aged 75 Years and Older With Established Atherosclerotic Cardiovascular Disease

OBJECTIVE

To explore the optimal low-density lipoprotein cholesterol (LDL-C) level in patients aged 75 years and older with established atherosclerotic cardiovascular disease (ASCVD).

PATIENTS AND METHODS

We conducted a retrospective multicenter cohort study of veterans aged 75 years and older with ASCVD who were regularly hospitalized or medically examined in 15 medical institutions in southern China from January 1, 2006, to December 31, 2013. Follow-up continued through October 1, 2021. The time-weighted average (TWA) LDL-C level represented the average LDL-C level during follow-up. Participants were divided into TWA LDL-C groups of 55.0 mg/dL or lower, 55.1 to 70.0 mg/dL, 70.1 to 85.0 mg/dL, 85.1 to 100.0 mg/dL, and greater than 100.0 mg/dL. The subgroup with LDL-C levels lower than 55.0 mg/dL was further subdivided into groups with LDL-C levels from 40.1 to 55.0 mg/dL and 40.0 mg/dL or less. The association of TWA LDL-C levels with outcomes was evaluated with Cox proportional hazards models.

RESULTS

Overall, 6387 patients aged 75 years or older with ASCVD were included (mean age, 79.4 years). In total, 4267 major adverse cardiovascular events, 1518 stroke events, and 515 myocardial infarction events occurred during a mean follow-up of 12.7 years. Generally, lower TWA LDL-C level was associated with a lower risk of cardiovascular events but was not associated with a higher risk of adverse events in elderly individuals with ASCVD, with the lowest cardiovascular risk observed for LDL-C levels of less than 55.0 mg/dL. After multivariable adjustment, the risk of a major adverse cardiovascular event was 1.30 (95% CI, 1.26 to 1.34; P<.001) for a per SD increment in TWA LDL-C level. Compared with TWA LDL-C levels of 40.1 to 55.0 mg/dL, TWA LDL-C levels of 40.0 mg/dL or less were associated with an increased risk of hemorrhagic stroke (hazard ratio, 3.71; 95% CI, 1.89 to 7.26).

CONCLUSION

Low-density lipoprotein cholesterol levels from 40.1 to 55.0 mg/dL exhibited the maximum cardiovascular benefit in patients aged 75 years and older who had ASCVD. Lowering LDL-C levels to 40.0 mg/dL or less might increase the risk of hemorrhagic stroke.

Effect of pitavastatin and atorvastatin on regression of atherosclerosis assessed using intravascular ultrasound: a meta-analysis

BACKGROUND

The aim of this study is to compare the efficacy and safety of pitavastatin and atorvastatin using data from randomized-controlled trial pooled together by means of a meta-analysis and decide which is better.

METHODS

PubMed, CENTRAL, Web of Knowledge, and ClinicalTrials.gov website were searched for randomized-controlled trials published until October 2016. Eligible studies comparing pitavastatin with atorvastatin head to head and reporting the outcome of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), glycated hemoglobin, and intravascular ultrasound evaluation were enrolled. Heterogeneity was assessed by using the I statistic, and the extracted data were estimated by fixed-effects model.

RESULTS

Eleven trials including a total number of 1733 participants were identified. Compared with atorvastatin, changes in the mean differences of LDL-C and HDL-C were 2.51 [95% confidence interval (CI): 1.17-3.86; I=48%; P=0.0003] and 2.17 (95% CI: 1.42-2.91; I=40%; P<0.00001), respectively, for pitavastatin. The changes in the mean differences of glycated hemoglobin was -0.15 (95% CI: -1.44-1.15; I=0%; P=0.83) for pitavastatin compared with atorvastatin. For plaque volume, lumen volume, and external elastic membrane, the changes are -0.93 (95% CI: -3.04-1.19; I=50%; P=0.39), 0.17 (95% CI: -2.91-3.26; I=0%; P=0.91), and -0.43 (95% CI: -1.96-1.11; I=4%; P=0.58), respectively, for pitavastatin versus atorvastatin.

CONCLUSION

In this study, pitavastatin seems to be less effective in reducing LDL-C and elevating HDL-C level compared with atorvastatin. Moreover, there is no significant difference in changes of glycated hemoglobin and intravascular ultrasound evaluation between pitavastatin and atorvastatin.

Lipid Target in Very High-Risk Cardiovascular Patients: Lesson from PCSK9 Monoclonal Antibodies

The role of low-density lipoproteins (LDLs) as a major risk factor for cardiovascular disease has been demonstrated by several epidemiological studies. The molecular basis for LDLs in atherosclerotic plaque formation and progression is not completely unraveled yet. Pharmacological modulation of plasma LDL-C concentrations and randomized clinical trials addressing the impact of lipid-lowering interventions on cardiovascular outcome have clearly shown that reducing plasma LDL-C concentrations results in a significant decrease in major cardiovascular events. For many years, statins have represented the most powerful pharmacological agents available to lower plasma LDL-C concentrations. In clinical trials, it has been shown that the greater the reduction in plasma LDL-C concentrations, the lower the rate of major cardiovascular events, especially in high-risk patients, because of multiple risk factors and recurrent events. However, in a substantial number of patients, the recommended LDL target is difficult to achieve because of different factors: genetic background (familial hypercholesterolemia), side effects (statin intolerance), or high baseline plasma LDL-C concentrations. In the last decade, our understanding of the molecular mechanisms involved in LDL metabolism has progressed significantly and the key role of proprotein convertase subtilisin/kexin type 9 (PCSK9) has emerged. This protein is an enzyme able to bind the LDL receptors (LDL-R) on hepatocytes, favoring their degradation. Blocking PCSK9 represents an intriguing new therapeutic approach to decrease plasma LDL-C concentrations, which in recent studies has been demonstrated to also result in a significant reduction in major cardiovascular events.

Flow Mediated Dilatation, Carotid Intima Media Thickness, Ankle Brachial Pressure Index and Pulse Pressure in Young Male Post Myocardial Infarction Patients in India

INTRODUCTION

Due to increase in Coronary Artery Disease (CAD) at a younger age, we should try to diagnose atherosclerotic process and population at risk, at the earliest. Flow Mediated Dilatation (FMD), Carotid Intima-Media Thickness (CIMT) and Ankle-Brachial Pressure Index (ABI) are probable markers for early atherosclerosis and may be useful in coronary risk stratification.

AIM

To compare and correlate the FMD, CIMT, ABI and Pulse Pressure (PP) in young male patients of Myocardial Infarction (MI) with age and sex matched healthy controls.

MATERIALS AND METHODS

Eighty male patients of MI aged ≤45 years, who presented to the Cardiac Care Unit and Department of Medicine of Guru Teg Bahadur Hospital, Delhi, India, from November 2010 to April 2012 were recruited consecutively for this case control study and same number of age and sex matched healthy controls were also analyzed. Six weeks after MI, FMD of the brachial artery, intima media thickness of carotid artery, ABPI and PP were measured in the cases and compared with healthy controls.

RESULTS

The FMD was lower among young patients of MI than controls (p<0.001). CIMT was higher among cases than controls (p=0.001). ABI was lower among cases than controls (p<0.001). Compared to controls, PP was higher among cases (p=0.001). In all subjects, a negative correlation between FMD and CIMT (r=-0.220, p=0.005) and a positive correlation between FMD and ABPI (r=0.304, p<0.001) was found. A statistically significant negative correlation was found between endothelial dependent FMD and PP among cases and control groups (r=-0.209, p=0.007).

CONCLUSION

Biophysical parameters were deranged in young post MI patients. Majority of our young male patients fell in low risk Framingham risk score but still they manifested with CAD. Despite six weeks of treatment among young male patients of MI, various biophysical parameters were still deranged.

Plasma Levels of Inflammatory Biomarkers in Peripheral Arterial Disease: Results of a Cohort Study

Previous research analyzed the level of plasma inflammatory markers in patients with coronary disease, but very few studies have evaluated these markers in patients with peripheral arterial disease (PAD). The objective of this study was to investigate the plasma levels of inflammatory markers in patients with PAD and in healthy controls. The following plasma levels of biomarkers were measured in 80 patients with PAD (mean age 68 ± 5 years) and in 72 healthy participants (mean age 67 ± 6 years): interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), L-selectin (LS), neopterin (N), P-selectin (PS), E-selectin (ES), vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and matrix metalloproteinase 2 (MMP-2), and 9 (MMP-9). Significantly higher levels of IL-6 (P < .001), TNF-α (P < .0001), ES (P < .0001), LS (P < .0001), PS (P < .0001), ICAM-1 (P < .001), VCAM-1 (P < .001), N (P < .001), MMP-2 (P < .001), and MMP-9 (P < .005) were found in the patients with PAD. Patients with PAD show a inflammation marker profile different from that of control participants. Reducing the high plasma levels of inflammatory markers could be a new therapeutic approach both for the prevention and the treatment of PAD.

Does statin therapy reduce plasma VEGF levels in humans? A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The effect of statins on plasma concentrations of vascular endothelial growth factor (VEGF), the main angiogenic growth factor with pro-inflammatory and atherogenic properties, is controversial. A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to obtain a conclusive result in humans.

METHODS

PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched to identify RCTs investigating the impact of statins on plasma VEGF concentrations. A random-effects model and the generic inverse variance method were used for quantitative data synthesis. Meta-regression, sensitivity analysis and publication bias assessments were performed using standard methods.

RESULTS

Eight RCTs examining the effects of statins on plasma VEGF concentrations were included. Meta-analysis suggested a significant reduction of plasma VEGF levels following statin therapy (weighed mean difference: -19.88 pg/mL, 95% CI: -35.87, -3.89, p=0.015). VEGF reductions were observed in the subsets of trials with treatment durations ≥4 weeks (-19.54, -37.78, -1.30, p=0.036), LDL-C reductions ≥50 mg/dL (-28.59, -43.68, -13.50, p<0.001), lipophilic statins (-22.31, -40.65, -3.98, p=0.017), and diseased populations (-21.08, -39.97, -2.18, p=0.029), but not in the opposite subsets. Meta-regression also suggested a significant association between changes in plasma VEGF levels and LDL-C changes, treatment duration, but not molar dose of statins.

CONCLUSIONS

These results suggest a significant reduction in plasma VEGF concentrations following statin therapy. This effect depends on duration of treatment, LDL-lowering activity, lipophilicity of statins, and health status of studied individuals. Further RCTs are needed to explore if the VEGF reduction is implicated in the statin benefits on cardiovascular outcomes.

Patient understanding of the importance of statin use in the perioperative period

OBJECTIVE

Perioperative hydroxy-3-methyl glutaryl coenzyme A reductase inhibitors (statins) have been shown to decrease morbidity and mortality after noncardiac surgery. The objective of this study was to assess patient understanding of the potential benefits of perioperative statins in a select population already on chronic therapy. A secondary aim was to determine the frequency with which patients recalled having a discussion with their provider regarding perioperative statins.

DESIGN

Survey.

SETTING

Teaching hospital.

PARTICIPANTS

Patients taking daily statins presenting to a preoperative medical evaluation clinic were offered a 12-question survey that assessed their understanding of the potential benefit of taking the medication in the perioperative period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred thirty-two patients completed the questionnaire. The mean age was 68.3 years (standard deviation, 9.0); 42% were female. The most frequent surgical referral to the clinic was orthopedics, at 36%. The most common statin prescribed was atorvastatin, in 35% of patients. Twenty-seven percent of patients (n = 36) recognized that perioperative statins are beneficial; 44% of these patients (n = 14) cited decreased cholesterol during the procedure as the reason, representing 12% of the total sampled population. Twenty-two percent (n = 8) of those recognizing the benefit of perioperative statins identified a decrease in the risk of heart attack or death as the reason. This represented only 6% of the total sample. One percent of surgeons mentioned statins in relation to the planned surgery; 2% of primary or prescribing physicians mentioned the medication in relation to surgery.

CONCLUSIONS

This study suggested low patient understanding of the potential importance and reasons for perioperative statins. In addition, this study also suggested that the information regarding the importance of perioperative statins is not being relayed to the patient at the level of the surgeon or primary care physician. All physicians involved in perioperative care can offer improved patient education to promote compliance with statin therapy in hopes of a favorable impact on perioperative outcomes.

Statins and contrast-induced acute kidney injury with coronary angiography

BACKGROUND

Contrast-induced acute kidney injury is an adverse outcome resulting from radiocontrast medium exposure during coronary angiography and percutaneous coronary intervention.

METHODS

A systematic search was conducted to retrieve studies that investigated the impact of statin exposure before coronary angiography or percutaneous coronary intervention on the development of contrast-induced acute kidney injury. The primary outcome was the development of contrast-induced acute kidney injury. We separately analyzed statin/placebo comparisons and high-/low-dose statin comparisons.

RESULTS

Fifteen randomized controlled trials met inclusion criteria: 11 studies with statin-naïve subjects, 2 studies with chronic statin users, and 2 studies with unspecified prior statin exposure. Statin exposure reduced the risk of contrast-induced acute kidney injury relative to placebo (relative risk [RR] 0.63, P = .01) with a nonsignificant reduction in the need for hemodialysis (RR 0.25, P = .08). This benefit was also observed in high-dose versus low-dose statin trials (RR 0.46, P = .004), in statin-naïve patients (RR 0.53, P <.0001), and with all studied statins. Higher statin exposure reduced contrast-induced acute kidney injury in patients with acute coronary syndromes compared with placebo or low-dose statins (RR 0.49, P <.00001), with no significant benefit among patients undergoing elective procedures (RR 0.86, P = .50). Subgroup analyses confirmed the benefit of statins in patients with diabetes, chronic kidney disease, congestive heart failure, and those receiving >140 mL of contrast dye.

CONCLUSION

Statin therapy is effective at reducing the risk of contrast-induced acute kidney injury. It should thus be considered, at least on a short-term basis, for patients at increased risk of this complication.

One-Year Clinical Outcomes among Patients with Metabolic Syndrome and Acute Myocardial Infarction

Background and Objectives

Metabolic syndrome (MetS) is an important risk factor for cardiovascular disease. However, the clinical outcome of acute myocardial infarction (AMI) with MetS has not been well examined. The purpose of this study was to evaluate the clinical outcomes of AMI patients with MetS.

Subjects and Methods

We evaluated a total of 6352 AMI patients who had successful percutaneous coronary interventions and could be identified for MetS between 2005 and 2008 at 51 hospitals participating in the Korea Acute Myocardial Infarction Registry. They were divided into 2 groups according to the presence of MetS: the MetS group (n=2493, 39.2%) versus the Non-MetS group (n=3859, 60.8%). In addition, 4049 AMI patients with high levels of low density lipoprotein-cholesterol (LDL-C) (≥100 mg/dL) among them, were divided into the MetS group (n=1561, 38.6%) versus the Non-MetS group (n=2488, 61.4%).

Results

In the overall population, there was no significant difference in 12-month the major adverse cardiac events (MACE) rate between the 2 groups. However, the MetS group showed a significantly higher 12-month MACE rate in the high LDL-C population. Multivariate analysis showed that MetS was an independent prognostic factor for 12-month MACE {hazard ratio (HR) 1.607, 95% confidence interval (CI) 1.027 to 2.513, adjusted p=0.038} and for 12-month target vessel revascularization (HR 1.564, 95% CI 1.092 to 2.240, adjusted p=0.015) in the high LDL-C population.

Conclusion

MetS patients with AMI in the overall population showed no significant difference in 12-month clinical outcomes. However, in patients with higher LDL-C ≥100 mg/dL, they showed significantly worse clinical outcome than Non-MetS patients. Therefore, it is important to ascertain the presence of MetS in AMI patients, and more aggressive therapy should be strongly considered for AMI patient with MetS.

Electronegative low-density lipoprotein increases C-reactive protein expression in vascular endothelial cells through the LOX-1 receptor

Objectives

Increased plasma C-reactive protein (CRP) levels are associated with the occurrence and severity of acute coronary syndrome. We investigated whether CRP can be generated in vascular endothelial cells (ECs) after exposure to the most electronegative subfraction of low-density lipoprotein (LDL), L5, which is atherogenic to ECs. Because L5 and CRP are both ligands for the lectin-like oxidized LDL receptor-1 (LOX-1), we also examined the role of LOX-1.

Methods and Results

Plasma LDL samples isolated from asymptomatic hypercholesterolemic (LDL cholesterol [LDL-C] levels, 154.6±20 mg/dL; n = 7) patients and normocholesterolemic (LDL-C levels, 86.1±21 mg/dL; P<0.001; n = 7) control individuals were chromatographically resolved into 5 subfractions, L1-L5. The L5 percentage (L5%) and the plasma L5 concentration ([L5]  =  L5% × LDL-C) in the patient and control groups were 8.1±2% vs. 2.3±1% (P<0.001) and 12.6±4 mg/dL vs. 1.9±1 mg/dL (P<0.001), respectively. In hypercholesterolemic patients treated with atorvastatin for 6 months (10 mg/day), [L5] decreased from 12.6±4 mg/dL to 4.5±1.1 mg/dL (P = 0.011; n = 5), whereas both [L5] and L5% returned to baseline levels in 2 noncompliant patients 3 months after discontinuation. In cultured human aortic ECs (HAECs), L5 upregulated CRP expression in a dose- and time-dependent manner up to 2.5-fold (P<0.01), whereas the least electronegative subfraction, L1, had no effect. DiI-labeled L1, internalized through the LDL receptor, became visible inside HAECs within 30 seconds. In contrast, DiI-labeled L5, internalized through LOX-1, became apparent after 5 minutes. L5-induced CRP expression manifested at 30 minutes and was attenuated by neutralizing LOX-1. After 30 minutes, L5 but not L1 induced reactive oxygen species (ROS) production. Both L5-induced ROS and CRP production were attenuated by ROS inhibitor N-acetyl cysteine.

Conclusions

Our results suggest that CRP, L5, and LOX-1 form a cyclic mechanism in atherogenesis and that reducing plasma L5 levels with atorvastatin disrupts the vascular toxicity of L5.

Placental growth factor in patients with decreased renal function

BACKGROUND

Patients with decreased renal function are characterized by high cardiovascular morbidity and mortality due to complications of premature atherosclerosis. Placental growth factor (PlGF) is a proatherogenic cytokine and new biomarker of cardiovascular events. The aim of this study was to determine PlGF levels and describe their relationship to renal function and risk factors of atherogenesis in patients with decreased renal function.

METHODS

The study group consisted of 114 subjects: 45 patients with various degrees of decreased renal function (CHRI), 31 long-term hemodialysis (HD) patients, and 38 age-matched healthy control subjects. PlGF was assessed immunochemically (enzyme-linked immunosorbent assay) and routine biochemical parameters were measured using standard laboratory methods.

RESULTS

PlGF levels were significantly increased in CHRI and HD patients compared to controls (10.5 ± 3.3 pg/mL in CHRI patients and 11.5 ± 3.4 pg/mL HD patients vs. 8.1 ± 1.8 pg/mL in controls, both p < 0.0001). In CHRI patients, PlGF was detectable in the urine, and its urine concentration correlated with its serum levels. In HD patients, PlGF correlated with low-density lipoproteins (r = 0.36, p < 0.05), but was not related to C-reactive protein levels. Higher levels of PlGF were found in CHRI patients with cardiovascular disease, compared with those free of such complication.

CONCLUSIONS

PlGF levels are increased in patients with decreased kidney function. PlGF is detectable in the urine, and serum and urine levels of PlGF are significantly interrelated. It is higher in CHRI patients with cardiovascular disease. Further studies are required to demonstrate the usefulness and significance of PlGF in patients with chronic kidney disease.

Intensive statin therapy compared with moderate dosing for prevention of cardiovascular events: a meta-analysis of >40 000 patients

AIMS

Statin therapy is associated with important benefits for patients at risk of, and with, established cardiovascular disease. There is widespread interest in whether intensive dosing of statins yields larger treatment effects. We aimed to determine if intensive dosing is clinically important using a meta-analysis of randomized clinical trials (RCTs).

METHODS

We conducted comprehensive searches of electronic databases from inception to December 2010. We included any RCT evaluating a larger dose with a clinically common dose. Two reviewers independently extracted data, in duplicate. We performed random-effects meta-analysis and a trial sequential analysis.

RESULTS

We identified 10 RCTs enrolling a total of 41 778 participants. Trials followed patients for a mean of 2.5 years. We did not find statistically significant effects on all-cause mortality [relative risk (RR) 0.92, 95% confidence interval (CI), 0.83-1.03, P = 0.14, I(2) = 38%] or cardiovascular disease (CVD) deaths (RR 0.89, 95% CI, 0.78-1.01, P = 0.07, I(2) = 34%). When we pooled the composite endpoint of coronary heart disease (CHD) death plus non-fatal myocardial infarction (MI), we found a significant protective effect of intensive statin dosing (RR 0.90, 95% CI, 0.84-0.96, P ≤ 0.0001, I(2) = 0%). We also found a significant effect on non-fatal MIs (RR 0.82, 95% CI, 0.76-0.89, P ≤ 0.0001, I(2) = 0%) and a significant reduction in the composite of fatal and non-fatal strokes (excluding transient ischaemic attacks) reported in 10 RCTs (RR 0.86, 95% CI, 0.77-0.96, P = 0.006, I(2) = 0%). A subgroup analysis of three trials examining acute coronary syndrome patients found significant effects on all-cause (RR 0.75, 95% CI, 0.61-0.91, P = 0.005, I(2) = 0%) and CVD mortality (RR 0.74, 95% CI, 0.59-0.94, P = 0.013, I(2) = 0%) with intensive dosing. Applying an analysis of optimal information size on the primary analysis, we found that the evidence for CHD death plus non-fatal MIs is conclusive. The evidence for CVD deaths alone is not yet conclusive.

CONCLUSIONS

Available evidence suggests that intensive statin therapy reduces the risk of non-fatal events and may have a role in reducing mortality.

Assessment of atherosclerosis: the role of flow-mediated dilatation

Evidence suggests that endothelial dysfunction is on the causal pathway for both atherogenesis and destabilization of established plaques. In this review, the role of flow-mediated dilatation (FMD) as a non-invasive method to assess endothelial function is discussed. Technical modifications and development of analysis software have significantly improved the variability of the method. Following a strict standardized protocol enables reproducible measurements to be achieved and export of the technique from specialized laboratories to population studies and multicentre settings. Endothelial function assessed by FMD has been shown to be affected by cardiovascular risk factors, to be related to structural arterial disease and to cardiovascular outcome, validating its use for studying the pathophysiology of arterial disease. Numerous studies have also demonstrated that it is responsive to physiological and pharmacological interventions. Flow-mediated dilatation provides unique opportunities in drug development programmes to assess an early rapidly responsive signal of risk or benefit, complementing endpoints of structural arterial disease and cardiovascular outcomes that take much longer and are more expensive.

Effects of atorvastatin on circulating CD34+/CD133+/ CD45- progenitor cells and indices of angiogenesis (vascular endothelial growth factor and the angiopoietins 1 and 2) in atherosclerotic vascular disease and diabetes mellitus

BACKGROUND

Cardiovascular disease (CVD) remains a major cause of morbidity and mortality, especially in the presence of diabetes, possibly because of endothelial damage. Increased circulating progenitor cells (CPCs) and increased plasma markers of angiogenesis [vascular endothelial growth factor (VEGF) and the angiopoietins (Ang-1 and -2)] may be evidence of this damage. Treatment with hydroxy-methyl-glutaryl (HMG-CoA) reductase inhibitors ('statins') improves outcomes in patients with vascular disease, including diabetic patients. We hypothesized that 80 mg per day atorvastatin influences CPC counts of VEGF and the angiopoietins in patients with atherosclerotic CVD with or without diabetes mellitus.

METHODS

Cardiovascular disease patients with diabetes mellitus (Group A, n = 14) and nondiabetic patients with CVD only (Group B, n = 10) took atorvastatin 80 mg per day for a period of 8-10 weeks. CPCs (CD34+/CD133+/CD45-) were defined by flow cytometry, plasma levels VEGF and Ang-1 and Ang-2 by ELISA).

RESULTS

Circulating progenitor cell counts increased (P < 0.001) in Group A compared with a nonsignificant change in Group B (P = 0.37). VEGF levels fell significantly in Group A (P = 0.04) but no significant change was seen in Group B (P = 0.16). Whilst Ang-1 remained unchanged (P = 0.41), Ang-2 levels increased markedly in both groups (P < 0.05). These effects were independent of LDL and total cholesterol changes but were associated with HDL changes.

CONCLUSION

High-dose atorvastatin increased circulating CPCs, reduced VEGF and increased Ang-2 in patients with diabetes and CVD, providing another possible pathophysiological mechanism for the beneficial effects of statins in CVD.

The role of flow-mediated dilatation in the evaluation and development of antiatherosclerotic drugs

PURPOSE OF REVIEW

The present article reviews the use of flow-mediated dilatation in clinical cardiovascular research. Its value as a surrogate tool for development of antiatherosclerotic drugs and noninvasive assessment of cardiovascular risk is also discussed.

RECENT FINDINGS

Atherosclerosis remains the leading cause of cardiovascular morbidity and mortality. Development of new drugs is required to target both the evolution of this disease and its clinical consequences. Noninvasive measures of arterial function and structure have been widely used as intermediate phenotypes in clinical trials. Numerous studies have demonstrated the interplay between vascular risk factors and endothelial function as assessed by flow-mediated dilatation in children and adults. Additionally, a number of studies have documented the prognostic value of the method.

SUMMARY

Detection of early arterial changes can prove particularly useful in clinical research for the development of antiatherosclerotic drugs. They permit identification of vascular toxicity as well as characterization of the safety and risk profile of a new cardiovascular treatment modality on vascular health. This approach is likely to prove cost-effective before embarking on large longitudinal studies to assess cardiovascular morbidity and mortality.

Update on therapeutic strategies to increase adiponectin function and secretion in metabolic syndrome

Changes in diagnostic criteria have impacted on the definition of the metabolic syndrome. The central aetiological importance of insulin resistance has lessened, while the role of other cardiovascular risk factors has progressively increased. Inflammatory mediators have also been identified as crucial targets for more selective therapies in metabolic syndrome. Among several pro-inflammatory factors, adiponectin has been shown to be associated with reduced cardiovascular risk in metabolic syndrome patients. Here, we review new therapeutic approaches, which could potentially increase adiponectin levels in metabolic syndrome.

Simvastatin treatment in subjects at high cardiovascular risk modulates AT1R expression on circulating monocytes and T lymphocytes

OBJECTIVE

Angiotensin II, through the activation of angiotensin II type 1 receptors, plays a crucial role in atherosclerosis. Statins may interfere with the effects of angiotensin II.

METHODS

We have investigated the expression of angiotensin II type 1 receptor, angiotensin II type 2 receptor and angiotensinogen on circulating monocytes and T-lymphocytes from subjects at high risk for vascular events before and during simvastatin treatment, and healthy controls. In-vitro experiments were also performed to assess the ability of simvastatin to interfere with angiotensin II signalling.

RESULTS

In comparison with controls, high-risk subjects had similar angiotensin II type 1 receptor expression on the cell membranes but significantly higher angiotensin II type 1 receptor mRNA levels at least in monocyte subsets whereas their expression on T cells was similar. Angiotensin II type 2 receptor mRNA expression was higher than controls in both monocytes and T lymphocytes. No differences were observed in angiotensinogen expression on monocytes while T lymphocytes of high-risk subjects show higher expression. One-month treatment of high-risk subjects with simvastatin resulted in a reduction of angiotensin II type 1 receptor mRNA without affecting angiotensin II type 2 receptor whereas angiotensinogen mRNA expression was reduced at least in monocytes. Incubation in vitro with simvastatin reduces the expression of angiotensin II type 1 receptor mRNA levels on monocytes from untreated subjects.

CONCLUSION

Simvastatin induces down-regulation of the angiotensin II type 1 receptor, interferes with angiotensin II activity in immune cells and contributes to the anti-inflammatory profile of statins that can explain the therapeutic effects of these drugs.

Statin reverses reduction of adiponectin receptor expression in infarcted heart and in TNF-α-treated cardiomyocytes in association with improved glucose uptake

Statin treatment improves insulin resistance in skeletal muscle. Thus this study assessed whether statin may affect the myocardial expression levels of AdipoR1 and AdipoR2, receptors of adiponectin that enhance insulin sensitivity, and whether statin may improve insulin resistance in cardiomyocytes. Myocardial infarction (MI) was created by the ligation of the left coronary artery in male mice. Expression levels of mRNA and protein levels of AdipoR1 but not of AdipoR2 were significantly decreased in the remote area as well as in the healed infarcted area in the left ventricles 4 wk after MI. Oral administration of pravastatin (50 mg·kg−1·day−1 for 4 wk after MI) reversed the decrease in myocardial expression levels of AdipoR1 independently of changes in serum lipid profiles and insulin levels. With the use of cultured cardiomyocytes, incubation with tumor necrosis factor (TNF)-α, a mediator of postinfarction myocardial dysfunction, inhibited AdipoR1 mRNA and protein expression levels. Coincubation of the cells with pravastatin reversed the inhibitory effects of TNF-α on AdipoR1 expression. In parallel, pravastatin reversed the TNF-α-induced decrease in globular adiponectin-induced 2-deoxy-d-[3H]glucose uptake in insulin-treated cultured cells. Moreover, this effect of pravastatin was inhibited by the suppression of AdipoR1 expression by small-interfering RNA specific for AdipoR1. Incubation with H2O2 reduced AdipoR1 expression in cultured cardiomyocytes that were attenuated by N-acetyl-l-cysteine or pravastatin. Pravastatin suppressed TNF-α-induced intracellular oxidants in cultured cardiomyocytes. In conclusion, pravastatin reversed the reduction of AdipoR1 expression in postinfarction mouse myocardium and in TNF-α-treated cardiomyocytes partly through an antioxidative mechanism in association with improved glucose uptake.

Angiotensin II type 1 receptor expression in polymorphonuclear leukocytes from high-risk subjects: changes after treatment with simvastatin

Statins may directly interfere with the effects of angiotensin (Ang) II, which is a key player in the pathogenesis of atherosclerosis (ATH). Ang II promotes a wide array of detrimental processes including a prominent proinflammatory effect, increasingly regarded as a target for therapeutic intervention. Because the proinflammatory effects of Ang II are exerted mainly through the activation of Ang II type 1 receptors (AT1Rs) the present study was devised to investigate by means of real-time polymerase chain reaction (PCR) and flow cytometry techniques the expression of such receptors on circulating polymorphonuclear leukocytes (PMNs) from subjects at high risk for vascular events before and during treatment with simvastatin and in sex- and age-matched healthy controls. In vitro experiments were also performed to assess the ability of simvastatin to interfere with Ang II signaling in human PMNs. In comparison to controls, high-risk subjects had similar AT1R expression on the cell membranes but significantly higher AT1R messenger ribonucleic acid (mRNA) levels. Treatment of high-risk subjects with simvastatin for 30 days resulted in a reduction of AT1R mRNA down to the levels of cells from healthy subjects. In vitro, Ang II-induced activation of the guanosine triphosphate (GTP)-binding protein Rac 1 in human PMNs was inhibited by simvastatin. In conclusion, simvastatin induces downregulation of AT1R expression, interferes with Ang II activity in PMNs, and contributes to the antiinflammatory profile of statins that can explain the therapeutic effects of these drugs.

Preoperative statins and infectious complications following cardiac surgery

PURPOSE

Recent observational studies have suggested that statins can decrease the incidence and severity of various infections including pneumonia and bacteremia. However, the effect of statins on post-cardiac surgery infection has not been adequately evaluated. Therefore we sought to determine whether preoperative statin use resulted in a reduction in infection following cardiac surgery.

METHODS

This was a cohort evaluation of all consecutive patients who underwent coronary artery bypass graft (CABG) and/or valve surgery at our institution between January 1, 2004 and August 31, 2006. Our primary outcome measure was the occurrence of at least one of the following postoperative infectious complications (pneumonia, bacteremia, sternal wound, leg vein harvest site infection, urinary tract infection, or tracheotomy site infection). We used multivariable logistic regression to control for potential confounding and to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs).

RESULTS

A total of 1934 patients were included in this evaluation of which 1248 received a statin preoperatively and 686 did not. Our study population was 66.3 +/- 11.6 years of age, 71.3% male; 37.2% underwent complex surgery, 3.6% were morbidly obese, and 32.0% were diabetic (each being previously identified as an independent predictor of infection following cardiac surgery). Patients receiving a statin preoperatively and not receiving a statin preoperatively varied in respect to a number of important pre- and peri- operative characteristics. Patients receiving preoperative statin therapy were more likely to have had a history of diabetes, chronic obstructive pulmonary disease or high cholesterol and to be smokers, but less likely to be undergoing urgent/emergent surgery or surgery utilizing a cardiopulmonary bypass pump (p < 0.05 for all comparisons). In total, 151 (7.8%) patients developed an infectious complication. Upon multivariable logistic regression, preoperative statin use was associated with a significant reduction in the development of infection (AOR; 0.67 (95% CI 0.46-0.99), p = 0.04). The use of a statin was not associated with a statistically significant reduction in any individual infection on its own (p > 0.08 for all).

LIMITATIONS

Patients were not randomized to receive statins or not. We did not have adequate power to evaluate individual infections.

CONCLUSIONS

Preoperative statin use is associated with a reduction in patients' odds of developing a postoperative infection following cardiac surgery.

Intensive statin therapy in acute coronary syndromes and stable coronary heart disease: a comparative meta-analysis of randomised controlled trials

BACKGROUND

Intensive statin therapy reduces major adverse cardiovascular events (MACE), but the effect on mortality is unclear.

OBJECTIVE

To determine whether intensive statin therapy reduces all-cause mortality compared with moderate statin therapy in patients with recent acute coronary syndromes (ACS) and stable coronary heart disease (CHD).

METHODS

Medline, Embase, the Cochrane Database, the internet, and conference proceedings from 1966 to 2006 were searched to identify relevant trials. Selection criteria were randomised allocation to intensive statin therapy (atorvastatin 80 mg/day, simvastatin 80 mg/day, or rosuvastatin 20-40 mg/day) versus moderate statin therapy, recent ACS or stable CHD at the time of randomisation, and > or =6 months of follow-up.

RESULTS

Six trials, encompassing 110 271 patient-years, were pooled. In patients with recent ACS, intensive statin therapy reduced all-cause mortality from 4.6% to 3.5% over 2.0 years (OR = 0.75, 95% CI 0.61 to 0.93). In patients with stable CHD, intensive statin therapy had no effect on all-cause mortality over 4.7 years (OR = 0.99, 95% CI 0.89 to 1.11). Overall, intensive statin therapy was associated with a reduction in MACE (OR = 0.84, 95% CI 0.77 to 0.91) and admissions to hospital for heart failure (OR = 0.72, 95% CI 0.62 to 0.83). Intensive statin therapy was also associated with an increase in hepatic transaminases >3 times normal (OR = 3.73, 95% CI 2.11 to 6.58) and a trend towards increased creatine kinase >10 times normal and/or rhabdomyolysis (OR = 1.96, 95% CI 0.50 to 7.63).

CONCLUSIONS

Compared with moderate statin therapy, intensive statin therapy reduces all-cause mortality in patients with recent ACS but not in patients with stable CHD.

Update on lipid-lowering therapy and LDL-cholesterol targets

Serum cholesterol has long been recognized as an important risk factor for the development and progression of atherosclerotic vascular disease. For more than 30 years, improved outcomes with lipid lowering have been demonstrated. As a result of these data, the National Heart, Lung, and Blood Institute (NHLBI) convened the National Cholesterol Education Program-Adult Treatment Panel I (NCEP ATP I). This panel and similar ones around the world have served to set the standards for lipid lowering in clinical practice. Subsequent revisions of these standards (NCEP ATP II and III) have led to greater focus being placed on LDL, and targets for lowering LDL levels being based on patients' risk of subsequent coronary disease events. Since the publication of the NCEP ATP III guidelines, several large-scale clinical trials of cholesterol lowering have been conducted, the findings of which have the potential to impact on clinical practice standards. In this article we focus on current guidelines for lipid-lowering therapy, review the results and implications of important completed clinical trials, and consider the utility of additional targets for preventive therapy, such as C-reactive protein and HDL. We also consider the prospects for treatments in development and future goals.

Physiological and therapeutic factors affecting cholesterol metabolism: does a reciprocal relationship between cholesterol absorption and synthesis really exist?

Cholesterol absorption and synthesis contribute to maintaining cholesterol homeostasis. Several physiological and therapeutic factors affect cholesterol homeostasis, including: genetics, circadian rhythm, body weight, plant sterols, ezetimibe, and statin therapy. The present objective is to determine the main vector, i.e. cholesterol absorption or synthesis, affected by each of these factors, and to examine whether an alteration in one vector is linked to a reciprocal change in the other. Current techniques used to assess cholesterol absorption and synthesis are also reviewed. Review of physiological factors affecting cholesterol metabolism suggest a reciprocal relationship between these two vectors. Carriers of the E2 isoform of apolipoprotein E and ATP binding cassette (ABC) G8 19H (exon 1 mutation) show a decrease in cholesterol absorption accompanied by a corresponding increase in synthesis. Circadian rhythm affects cholesterol synthesis, however, its effect on absorption has yet to be established. Obese subjects show an increase in cholesterol synthesis with a subsequent decrease in cholesterol absorption. Weight loss down regulates cholesterol synthesis, but has little or no effect on absorption. In the case of therapeutic factors, plant sterols and stanols inhibit cholesterol absorption, which results in a compensatory increase in synthesis. Ezetimibe also decreases intestinal absorption, while reciprocally increasing synthesis. Statin therapy down regulates synthesis, which is accompanied by a rise in absorption. These findings suggest that a change in one vector, fairly consistently, results in a compensatory and opposing change in the other. An understanding of this reciprocal relationship between cholesterol absorption and synthesis may allow for the development of more effective interventions for dyslipidemic disorders.

Statin Withdrawal: Clinical Implications and Molecular Mechanisms

Retrospective analyses of data from the Platelet Receptor Inhibition in Ischemic Syndrome Management (PRISM), the National Registry of Myocardial Infarction 4, and the Global Registry of Acute Coronary Events (GRACE) trials revealed that the benefits of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) on acute coronary outcomes are rapidly lost and outcomes worsened if statins are discontinued during a patient's hospitalization for an acute coronary syndrome. Withdrawal of statin therapy in the first 24 hours of hospitalization for non-ST-elevation myocardial infarction increased the hospital morbidity and mortality rate versus continued therapy (11.9% vs 5.7%, p<0.01). Data from the Treating New Targets (TNT) study, however, suggested that short-term discontinuation of statin therapy in patients with stable cardiac conditions may not substantially increase the risk of acute coronary syndromes. In patients with acute coronary syndromes who discontinue statins, the rapid increase in risk of an event may result not only from the lost benefits from the therapy, but also from rebound inhibition of vascular protective substances and activation of vascular deleterious substances. Statins inhibit cholesterol synthesis in vascular cells. By reducing levels of isoprenoid intermediates, statins increase the production of nitric oxide and downregulate angiotensin II AT(1) receptors, endothelin-1, vascular inflammatory adhesion molecules, and inflammatory cytokines. These benefits are rapidly lost and often transiently reversed when statins are acutely discontinued. Acute removal of pleiotropic effects and rebound vascular dysfunction may be more important in an acute coronary event, where inflammation promotes rupture of atherosclerotic plaques and inflammatory and prothrombosis markers are present in high concentration, than in stable chronic vascular disease. In the absence of data from randomized controlled trials, current information suggests that statin therapy should be continued, and possibly boosted, during hospitalization for an acute coronary syndrome. Because statins are discontinued during the early hospitalization of many patients, practitioners must ensure that statins are not omitted, unless contraindicated, from the treatment of patients with acute coronary syndromes.

Atorvastatin Increases Plasma Soluble Fms-Like Tyrosine Kinase-1 and Decreases Vascular Endothelial Growth Factor and Placental Growth Factor in Association With Improvement of Ventricular Function in Acute Myocardial Infarction

OBJECTIVES

This study examined whether atorvastatin increases plasma levels of soluble Fms-like tyrosine kinase 1 (sFlt-1) and reciprocally decreases vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) levels in patients with acute myocardial infarction (AMI).

BACKGROUND

Statins exert cardioprotective actions partly through anti-inflammatory actions. By capturing VEGF and PlGF in plasma, sFlt-1 acts as a natural inhibitor of VEGF and PlGF, which have proinflammatory properties.

METHODS

Left ventriculography and enzyme-linked immunosorbent assay of plasma levels of sFlt-1, VEGF, and PlGF were repeated after AMI in 50 consecutive patients with a first AMI. Patients were randomized to treatment with atorvastatin (10 mg/day; n=25) or placebo (n=25) within 3 days after AMI, and therapy was continued for 6 months.

RESULTS

The sFlt-1 levels were low in the acute phase, followed by an increase at 2 weeks after AMI, whereas free VEGF and PlGF levels were high in the acute phase, followed by a decrease at 2 weeks. Atorvastatin increased sFlt-1 levels and reciprocally decreased VEGF and PlGF levels at 6 months compared with placebo. The increase in sFlt-1 levels and the decrease in VEGF and PlGF levels were correlated with improvement of left ventricular ejection fraction during the follow-up period.

CONCLUSIONS

There was a reciprocal relationship between changes in sFlt-1 levels and changes in VEGF and PlGF levels after AMI; and atorvastatin increased sFlt-1 levels while decreasing VEGF and PlGF levels. These changes were associated with late improvement of post-MI ventricular function, and may represent an additional benefit of statin therapy.

Enhanced external counterpulsation improves endothelium-dependent vasorelaxation in the carotid arteries of hypercholesterolemic pigs

BACKGROUND

Enhanced external counterpulsation (EECP) has been demonstrated to be an effective method for the treatment of atherosclerotic vascular disease. However, the exact mechanism underlying the beneficial effects of EECP is not completely clear. We hypothesized that EECP leads to improvement in endothelial function, contributing to its clinical benefits.

METHODS

Fifteen male domestic pigs were initially divided into 2 dietary groups: one consumed a normal feeding (NF) of pig chow (n=5), and one consumed a high-fat (HF) pig chow (n=10). After 8 weeks on the NF or HF diet, 5 HF pigs received EECP treatment (HF+EECP) 1 h daily for 6 weeks and the remaining 5 HF pigs continued to be fed by high cholesterol diet. At the end of 6-week EECP treatment, the carotid arterial rings from all of the pigs were harvested. Endothelium-dependent and -independent vasorelaxation to acetylcholine (ACh) and sodium nitroprusside (SNP) were measured in a dose-dependent manner.

RESULTS

The high fat diet resulted in increase in plasma cholesterol and triglyceride levels (p<0.05). Endothelium-dependent vasorelaxation was decreased in the HF group compared to the NF control (p<0.05). However, EECP treatment partially improved impaired endothelium-dependent vasorelaxation in the HF+EECP group compared to the HF control (p<0.05). Endothelium-independent vasorelaxation was not significantly different among the three groups.

CONCLUSIONS

Endothelium-dependent vasorelaxation is impaired in the hypercholesterolemic pigs. EECP treatment significantly improves hypercholesterolemia-induced diminished endothelium-dependent vasorelaxation. It suggests that amelioration in endothelial function may at least in part contribute to the beneficial effects of EECP treatment in clinical practice.

Optimal goals for statin use in patients with coronary artery disease

PURPOSE OF REVIEW

Coronary artery disease is the largest cause of premature death in the Western world. Lipid-lowering therapy with statins has revolutionized the management of this condition over the past decade.

RECENT DEVELOPMENTS

Successive clinical trials have lowered the treatment bar for statin therapy in patients with coronary artery disease. In addition to traditional markers of efficacy such as low-density lipoprotein cholesterol, emerging targets such as C-reactive protein are becoming recognized as important therapeutic goals.

SUMMARY

This review focuses on the important contributions to the literature during the past year and provides an expert opinion of the therapeutic goals for statin therapy.

Early time to benefit with intensive statin treatment: could it be the pleiotropic effects?

Acute coronary syndrome (ACS) is associated with a number of abnormalities in inflammation, endothelial function, and coagulation, all of which appear to be modulated by statins. We examined the time to benefit of different statin regimens in the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis in Myocardial Infarction 22 (PROVE IT-TIMI 22) trial and other ACS trials that compared statin therapies in patients with ACS. In PROVE IT-TIMI 22, apparent clinical benefit was observed as early as 30 days, with significant reduction in all-cause mortality, myocardial infarction, unstable angina requiring rehospitalization, revascularization performed 30 days postrandomization, or stroke observed as early as 4 months. In PROVE IT-TIMI 22, atorvastatin 80 mg lowered both low-density lipoprotein (LDL) cholesterol and C-reactive protein (CRP) at 30 days and 4 months to a greater extent than pravastatin 40 mg. Those who achieved the lowest LDL and the lowest CRP levels at 30 days after ACS had the lowest risk of acute cardiac events. The very early benefits of statin therapy appeared to be correlated with CRP reductions, which may relate to the intensity of the pleiotropic effects of statins.

Responsiveness of plasma lipids and lipoproteins to plant stanol esters

Plant stanols have been shown to reduce serum levels of low-density lipoprotein (LDL) cholesterol, and they are an attractive adjunct in dietary therapy for elevated LDL cholesterol. This investigation addressed 3 questions through metabolic studies in human subjects: (1) whether plant stanol esters given at higher doses than the 2-g/day dose recommended by the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) will provide additional LDL-lowering efficacy (study 1); (2) whether substantial reduction in LDL cholesterol can be obtained in postmenopausal women with hypercholesterolemia by addition of plant stanol esters to the diet (study 2); and (3) whether ATP III goals can be obtained by adding plant stanol esters to an LDL-lowering regimen in high-risk patients who retain LDL cholesterol levels in the above-optimal range (ie, 2.6 to 3.3 mmol/L [100 to 129 mg/dL]), despite ongoing statin therapy (study 3). Study 1 showed that maximal LDL lowering with plant stanols in the form of esters can be achieved at a dose of 2 g/day. Higher doses do not provide additional efficacy. Study 2 demonstrated that stanol esters can reduce LDL cholesterol levels in postmenopausal women by about 13%, which makes use of stanol esters attractive as a component of nondrug therapy in these women who generally are at relatively low risk for coronary heart disease. Finally, study 3 found that plant stanols provide additional lowering of LDL cholesterol when added to ongoing statin therapy. This makes plant stanols an attractive dietary component to help to achieve the goals of LDL-lowering therapy in patients requiring an LDL-lowering drug.