Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) Study Group. Prevention of cardiovascular events and death with pravastatin in patients with coronary heart disease and a broad range of initial cholesterol levels

Coronary heart disease in African Americans

African Americans have the highest overall mortality rate from coronary heart disease (CHD) of any ethnic group in the United States, particularly out-of-hospital deaths, and especially at younger ages. Although all of the reasons for the excess CHD mortality among African Americans have not been elucidated, it is clear that there is a high prevalence of certain coronary risk factors, delay in the recognition and treatment of high-risk individuals, and limited access to cardiovascular care. The clinical spectrum of acute and chronic CHD in African Americans is similar to that in whites. However, African Americans have a higher risk of sudden cardiac death and present more often with unstable angina and non-Q-wave myocardial infarction than whites. African Americans have less obstructive coronary artery disease on angiography, but may have a similar or greater total burden of coronary atherosclerosis. Ethnic differences in the clinical manifestations of CHD may be explained largely by the inherent heterogeneity of the coronary syndromes, and the disproportionately high prevalence and severity of hypertension and type 2 diabetes in African Americans. Identification of high-risk individuals for vigorous risk factor modification-especially control of hypertension, regression of left ventricular hypertrophy, control of diabetes, treatment of dyslipidemia, and smoking cessation--is key for successful risk reduction.

Cardiovascular disease in type 2 diabetes: challenge for treatment and prevention

Type 2 diabetes increases the risk of cardiovascular disease (CVD) two- to fourfold compared with the risk in non-diabetic subjects. Although type 2 diabetes is associated with a clustering of risk factors (small, dense low-density lipoprotein [LDL] particles, low high-density lipoprotein [HDL] cholesterol, high triglycerides, elevated blood pressure, obesity, central obesity, hyperinsulinaemia, hyperglycaemia, etc.), the cause for an excess risk of CVD remains unknown. Recent drug treatment trials have indicated that the lowering of total and LDL cholesterol and blood pressure is similarly beneficial in diabetic and non-diabetic subjects. The treatment of hyperglycaemia reduces micro- and macrovascular complications in type 2 diabetic patients. Beta-blocking agents, angiotensin-converting enzyme inhibitors, aspirin, and thrombolytic therapy are also effective in the treatment of CVD amongst diabetic patients.

Treatment of older persons with hypercholesterolemia with and without cardiovascular disease

Hypercholesterolemia is a risk factor for new coronary events in older men and women. Secondary prevention trials have demonstrated in persons with coronary artery disease (CAD) and hypercholesterolemia that statin drugs reduced in older persons all-cause mortality, cardiovascular mortality, coronary events, coronary revascularization, stroke, and intermittent claudication. Statins have also been shown to slow progression of coronary atherosclerotic plaques in persons with CAD, to reduce restenosis after coronary stent implantation, and to decrease myocardial ischemia in persons with CAD. Older men and women with CAD, prior atherothrombotic brain infarction, peripheral arterial disease, or extracranial carotid arterial disease and a serum low-density lipoprotein (LDL) cholesterol level higher than 125 mg/dl despite diet should be treated with statin drug therapy to lower the serum LDL cholesterol level below 100 mg/dl. Primary prevention trials have shown that statins were also effective in reducing cardiovascular events in older persons with hypercholesterolemia. On the basis of data from the Air Force/Texas Coronary Atherosclerosis Prevention Study, the physician should consider using statins in persons aged 65-80 years without cardiovascular disease with a serum LDL cholesterol level above 130 mg/dl and serum high-density lipoprotein cholesterol level below 50 mg/dl.

Public health genetics: an emerging interdisciplinary field for the post-genomic era

Public health genetics is an exciting interdisciplinary area that brings all the public health sciences to bear on the emerging challenge of interpreting the medical and public health significance of genetic variation within populations. Sequencing of the human genome will generate an avalanche of genetic information to be linked with information about microbial, chemical, and physical exposures; nutrition, metabolism, lifestyle behaviors, and medications. The public health genetics mini-symposium in this volume includes articles dealing with educational innovations, host-pathogen interactions in infectious diseases, nutrition/genetic interactions in cancers, and population screening for hemochromatosis. Additional topics addressed here are ecogenetics and risk assessment, the genetics of unhealthful behaviors, and ethical and policy issues. Finally, a set of principles for community-based health research in populations is presented as a public health-oriented counterpart to the principle of autonomy and the practice of informed consent that have become key elements of ethics in medical care and medical research with individuals.

Effect of pravastatin on frequency of fracture in the LIPID study: secondary analysis of a randomised controlled trial. Long-term Intervention with Pravastatin in Ischaemic Disease

BACKGROUND

Statins inhibit the same biochemical pathway as aminobisphosphonates, therefore these cholesterol-lowering agents may have a beneficial effect on osteoporosis. This possibility has been supported by the finding that some statins also stimulate bone formation, and by observational studies suggesting that patients using statins have higher bone densities and lower fracture rates than controls. To assess whether statins have clinically significant effects on bone, we studied the frequency of fractures in a large randomised controlled trial of these agents.

METHODS

9014 patients (17% women, median age 62 years) with ischaemic heart disease were randomly assigned pravastatin 40 mg daily or placebo and followed up for a mean of 6.0 years. Fractures were ascertained from adverse-event reports.

FINDINGS

101 patients in the placebo group were admitted to hospital for fracture compared with 107 in the pravastatin group (hazard ratio 1.05 [95% CI 0.80-1.37]). When patients with fractures not necessitating hospital admission were added, the total number of patients having a fracture was 183 in the placebo group and 175 in the pravastatin group (0.94 [0.77-1.16]). Separate analyses for women alone and for individuals aged 65 years and over gave similar results.

INTERPRETATION

These findings offer no support for the hypothesis that statins have a significant effect on fracture risk. However, this study was not of an osteoporotic population, and fracture rate, although clinically important, is an insensitive index of effects on bone. Statins should not be used to prevent osteoporosis until there is evidence for their efficacy based on randomised controlled trials.

The Year in Review: Cardiology

Overall, the evolution of the management of a broad spectrum of cardiovascular disease states has occurred primarily as a result of randomized, controlled clinical trials that have been conducted and published over time. During the past two years, the results of numerous clinical trials have certainly had a significant impact on the ways in which practitioners have treated conditions such as chronic heart failure, cardiac arrhythmias, ischemic heart disease, dyslipidemias, and hypertension. This review article summarizes the results of several key clinical trials that evaluated various treatment strategies for these five cardiovascular disease states and attempts to provide insight as to how these findings can be incorporated into clinical practice.

The lack of cardiovascular risk factor management in patients with critical limb ischaemia

AIM

to define the level of management of cardiovascular risk factors in patients treated for critical limb ischaemia in a vascular surgical setting.

MATERIALS AND METHODS

retrospective review of all (n =147) patients operated on for critical lower extremity ischaemia in 1998. We included pre- and postoperative cardiac events.

RESULTS

only eight (5%) (95% CI; 2-9) were on lipid lowering treatment and 58 (39%) (95% CI; 31-47) using acetylsalicylic acid.

CONCLUSIONS

only a minority of patients operated on for CLI were receiving adequate cardiovascular risk factor modification.

Efficacy and tolerability of fluvastatin extended-release delivery system: a pooled analysis

BACKGROUND

At high doses, the pharmacokinetics of fluvastatin immediate-release (IR) are nonlinear, possibly due to saturation of hepatic uptake. Fluvastatin delivery to the liver in a slower but sustained fashion would be expected to avoid hepatic saturation without elevating systemic drug levels.

OBJECTIVE

This pooled analysis compared the efficacy and tolerability of extended-release (XL) 80-mg and IR 40-mg formulations of fluvastatin in lowering low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels and raising high-density lipoprotein cholesterol (HDL-C) levels in patients with hypercholesterolemia.

METHODS

Data were pooled from 3 double-blind, randomized, active-controlled, multicenter, parallel-group studies that compared changes in lipid and apolipoprotein levels with fluvastatin XL 80 mg at bedtime (HS) with changes in fluvastatin IR 40 mg HS or BID in patients aged > or =18 years with primary hypercholesterolemia (consistently elevated LDL-C level [> or =160 mg/dL] and plasma TG levels < or =400 mg/dL). The primary efficacy variable was percent change in LDL-C from baseline.

RESULTS

The pooled analysis provided an intent-to-treat efficacy study population of 1674 patients. At 4 weeks, fluvastatin XL 80 mg HS reduced LDL-C levels by a mean of 36.3% (median 38%), significantly greater than a mean reduction of 25.9% (median 27%) seen with fluvastatin IR 40 mg HS, and an incremental additional mean reduction in LDL-C of 10.4% (P < 0.001). At 4 and 24 weeks, fluvastatin XL 80 mg HS provided an LDL-C reduction equivalent to fluvastatin IR 40 mg BID (P < 0.001 for noninferiority). Significant, dose-related changes in HDL-C, LDL-C:HDL-C ratio, total cholesterol, TG, and apolipoprotein A-I and apolipoprotein B levels also occurred. Mean HDL-C level increased by 8.7% and median TG level decreased by 19% with fluvastatin XL 80 mg HS (P < 0.001 and P < 0.05 vs fluvastatin IR 40 mg HS, respectively). Maximum mean increases in HDL-C level (21%) and median decreases in TG level (31%) with fluvastatin XL 80 mg HS occurred in patients with type IIb dyslipidemia and the highest baseline TG. Adverse events were mild, with similar frequency in all treatment groups.

CONCLUSIONS

Once-daily administration of fluvastatin XL 80 mg provides enhanced efficacy with an additional 10.4% reduction in LDL-C levels compared with fluvastatin IR 40 mg HS, and superior increases in HDL-C levels, particularly in patients with elevated TG levels (P < 0.05 vs fluvastatin IR 40 mg HS). Fluvastatin XL 80 mg HS has a good tolerability profile and is effective as starting and maintenance lipid-lowering treatment in patients with type II hypercholesterolemia.

Changing the practice of cardiovascular medicine

Five large randomized trials of statins in primary and secondary prevention show the benefits of lipid-modifying therapy on cardiac morbidity and mortality. Evidence is beginning to accumulate showing that early and aggressive treatment of patients with acute coronary syndromes (acute myocardial infarction or unstable angina) can result in reduced mortality and morbidity and imparts a variety of mechanistic benefits. Nevertheless, recent surveys of coronary heart disease prevention in Europe and the US indicate that current evidence-based management of risk factors such as hypercholesterolemia is not uniformly employed. In fact, in Europe, only about a third of patients discharged from the hospital after an acute coronary syndrome are receiving prescriptions for statins. In US, more than a fourth of adults are eligible for treatment according to national guidelines but two thirds of them do not receive it. Among those treated, a considerable number do not reach their target levels. Therefore, strategies are needed to improve prescribing patterns among physicians and compliance among patients. It is essential that clinicians be aware of the evidence base supporting early and aggressive treatment of patients with acute coronary syndromes and that this is communicated to all clinicians involved in their care of patients with acute coronary syndromes.

Antioxidants and endothelial dysfunction in hyperlipidemia

Endothelial function is abnormal in a variety of diseased states such as hypercholesterolemia and atherosclerosis. This may be secondary to decreased synthesis of nitric oxide (NO) and/or increased degradation of NO due to interaction with superoxide anions. More recent experimental observations demonstrate increased production of superoxide in hyperlipidemia, suggesting that endothelial dysfunction in these states is in part secondary to increased NO metabolism. Enzymes proposed to be involved in increased superoxide production may include xanthine oxidase, the NO synthase, and the NAD(P)H oxidase. Superoxide rapidly reacts with NO to form peroxynitrite (ONOO-), a highly reactive intermediate with cytotoxic properties. Despite experimental evidence for the oxidative stress concept in causing endothelial dysfunction, the results of recent randomized trials to test the influence of antioxidants on coronary event rates and prognosis in patients with coronary artery disease were very disappointing. In all of these studies the use of vitamins such as vitamin E failed to improve the prognosis. In contrast, treatment with angiotensin converting enzyme inhibitors or cholesterol- lowering drugs improved endothelial dysfunction, prevented the activation of superoxide-producing enzymes in cholesterol-fed animals, reduced coronary event rates, and improved prognosis in patients with coronary artery disease. Therefore, inhibition of superoxide production at the enzymatic level rather than symptomatic superoxide scavenging may be the better choice of treatment.

Anti-inflammatory effects of simvastatin in subjects with hypercholesterolemia

AIMS

Beneficial effects of statins in preventing cardiovascular events may depend, at least in part, on their anti-inflammatory action. The aim of the study was to assess the influence of simvastatin and aspirin on serum levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in hypercholesterolemic subjects.

METHODS AND RESULTS

In 33 asymptomatic men with total cholesterol (TC) >6.5 mmol l(-1) and in 25 men with coronary heart disease and borderline-high cholesterol levels (between 5.2 and 6.5 mmol l(-1)) chronically treated with low-dose aspirin (75 mg/d), serum levels of CRP, TNF-alpha, IL-6, and IL-8 were determined before and after a 3-month simvastatin therapy (20-40 mg daily). In the former group, these markers of inflammation were also measured before and after a 2-week treatment with aspirin (300 mg/d), implemented prior to and in combination with simvastatin. A distinct reduction of CRP and TNF-alpha was found in both groups; IL-6 levels were decreased only in subjects with marked hypercholesterolemia. Aspirin had no effect on the anti-inflammatory action of simvastatin.

CONCLUSIONS

In men with hypercholesterolemia simvastatin treatment lowers serum levels of CRP and proinflammatory cytokines. Low-dose aspirin does not add to the anti-inflammatory action of simvastatin.

Clinical relevance of statins: instituting treatment early in acute coronary syndrome patients

The efficacy of statins in lowering the total and low-density lipoprotein cholesterol and reducing the risk of cardiac events is now well established. The secondary prevention studies started treatment several months after the acute event. However, the greatest risk of recurrence is shortly after the index event. Recent evidence from small-scale clinical trials shows that standard doses of statins can be both safe and effective when given early after an acute coronary event, including early after thrombolytic therapy for myocardial infarction. Angiographic studies have shown beneficial effects of pravastatin on coronary stenosis when initiated after a coronary event. While none of these studies have been powered to demonstrate an effect on outcome, each has shown a reduction in major cardiovascular events. Two large observational studies have shown a reduction in 6- and 12-month risk-adjusted mortality among post-MI patients treated early with statins. Large-scale trials of all statins are now in progress to evaluate further the efficacy of early initiation of statin therapy in acute coronary syndromes. The largest of these is the Australian Pravastatin Acute Coronary Treatment (PACT) study, which will compare early outcomes in patients treated with pravastatin versus placebo prescribed within the first 24 h of an acute coronary event.

Mechanisms of acute coronary syndromes and the potential role of statins

The conventional concepts of the pathogenesis of acute coronary syndromes are changing. High-risk lesions are not necessarily the angiographicaly 'tight' stenoses. Rather, vulnerable lesions are those that are unstable, with a large lipid core and a thin fibrous cap. Plaque instability is closely related to the development of inflammation within the intima and acute coronary syndromes result from rupture of a vulnerable atherosclerotic plaque. Stabilization of lesions by modification of structure and content, rather than simple improvement in the luminal diameter, provides a new therapeutic target. Stabilization may be accomplished through lifestyle changes and appropriate pharmacologic therapy. In the past few years, it has become evident that a major beneficial effect of statins is to induce plaque stability and regression. In fact, statins, in addition to lowering low-density lipoprotein cholesterol, have a variety of pleiotropic, or cholesterol-independent, effects that make them a particularly suitable choice in patients with acute coronary syndromes. Among these are improvements in endothelial function, smooth muscle cells, thrombus formation/platelet function, and inflammation.

Coronary Artery Disease in Postmenopausal Women

Many important developments recently have been made in the treatment and prevention of coronary artery disease (CAD) in postmenopausal women. Substantial evidence supports focusing on comprehensive risk factor modification based on the "ABCs" of CAD management from the American College of Cardiology, the American Heart Association, and the American College of Physicians-American Society of Internal Medicine guidelines on chronic stable angina. This approach emphasizes cardiovascular risk factor interventions that include antiplatelet agents, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, cholesterol-lowering medications, diabetes control, and counseling on diet and exercise. Despite the expanding available literature, many questions on CAD in postmenopausal women remain unanswered and await the publication of ongoing and future research. The unexpected findings from the HERS (Heart and Estrogen/progestin Replacement Study) failed to show a benefit of hormone replacement therapy (HRT) in reducing the risk of subsequent events in postmenopausal women with CAD, and instead reported an early increase in CAD events. Based on the data available so far, we advise against starting HRT in postmenopausal women with a recent coronary event for the sole purpose of CAD prevention. For women with acute coronary syndromes, prompt angiography and revascularization should be considered.

[Risk factor prevalence and drug treatment in coronary patients at hospital discharge. Results of a national multicenter registry (3C Program)]

INTRODUCTION AND OBJECTIVES

Based on the results of clinical trials the guidelines of international societies recommend secondary prevention in patients. Several surveys have shown that the application of these guidelines in clinical practice is not adequate. The aim of this study was to determine the practical application of the recommendations of these guidelines and drug prescription in patients with coronary heart disease on hospital discharge.

METHODS

We included 3,215 coronary patients (myocardial infarction, angina and post-revascularization) discharged from 25 Spanish hospitals. We studied the prevalence of risk factors and the medical treatment on discharge in relation to gender, age, and clinical diagnosis.

RESULTS

We found a significantly higher prevalence of risk factors, except for smoking, in women. With regards to age and diagnosis neither was, the prevalence uniform, with an increase in hypertension and diabetes being predominantly seen in the elderly as well as angina patients. Fifty-six point three percent of the patients showed a total cholesterol greater than 200 mg/dl and 88% demonstrated a LDL-cholesterol greater than 100 mg/dl. The prevalence of hypercholesterolemia and low HDL was higher among women. The prescription of betablockers and lipid-lowering drugs is low, especially in women and in patients over the age of 64 years.

CONCLUSIONS

The registry of data concerning some risk factors in patient clinical files is poor. The prevalence of risk factors is higher in women. The prescription of betablockers and lipid-lowering drugs was lower than recommended, mainly among women and patients older than 64 years. There is a need for improvement in secondary prevention in coronary patients on hospital discharge.

Nutritional and medical therapy for dyslipidemia in patients with cardiovascular disease

Dyslipidemia is a significant risk factor for the progression of cardiovascular disease, particularly when associated with other risk factors. An understanding of the pathophysiology and risks for patients with atherosclerotic diseases of undertreated dyslipidemia is essential for the healthcare provider. In this article, a review of epidemiologic data regarding the role of lipid levels in cardiovascular disease prognosis is presented. A familiarity with current dietary and drug treatment of lipid disorders is at the core of an evidence-based approach to dyslipidemia management in the patient with established cardiovascular diseases.

[Cellular and molecular biology of atherosclerotic lesions]

The association of atherosclerosis with the most common risk factors including elevation of low density lipoprotein (LDL) levels, diabetes, hypertension and cigarette smoking, led to the hypothesis of "response to injury" to explain how the lesions develop. According to this hypothesis, one of the earliest events in atherogenesis is the accumulation of LDL in the arterial wall where they undergo oxidation. These LDL impair endothelial function, and thus, all the antiatherogenic properties of the endothelium. In addition, macrophages and smooth muscle cells take up these LDL, through different receptors, and become foam cells. The accumulation of foam cells in the arterial wall contributes to lesion development. Therefore, lesion development involves the activation of endothelial cells, as well as smooth muscle cells and monocytes/macrophages. In this activation different growth factors (PDGF, EGF, etc.), cytokines (IL-1b, TNFa, etc.) and the modified LDL themselves, play an important role. Through several signal transduction pathways these molecules activate transcription factors, such as the nuclear factor kappa B (NF-kB) or protooncogenes such as c-fos, c-myc, that regulate the expression of genes involved in the inflammatory/proliferative response of the lesions.

Clinical relevance of statins: their role in secondary prevention

Five large randomized clinical trials show the benefits of lipid lowering with statins on cardiac morbidity and mortality. Three of these were secondary-prevention trials--the Long-term Intervention with Pravastatin in Ischemic Disease (LIPID) study, Cholesterol and Recurrent Events (CARE), and Scandinavian Simvastatin Survival Study (4S). The CARE and LIPID studies, performed with pravastatin, comprise populations that are representative of the majority of patients with coronary disease in that they included subjects with 'average' cholesterol levels. The 4S study, using simvastatin, comprised a patient population with elevated lipid levels. Pooled data from three trials, CARE, LIPID, and the West of Scotland Coronary Prevention Study (WOSCOPS), were examined in the Pravastatin Pooling Project (PPP). Individual patient data from these three event trials were pooled into a single database, permitting subgroup analyses and providing increased power. In the PPP, pravastatin-treated patients had significantly lower all-cause mortality (7.9, vs. 9.8% in those receiving placebo, a relative risk reduction of 20%). Pravastatin treatment was associated with a significant 24% reduction in CHD mortality and a nonsignificant difference in other vascular deaths (17%) and noncardiovascular deaths (12%). However, the reductions in absolute risk were much larger in those with a history of coronary heart disease than in those without. In the combined analysis of CARE and LIPID, there was also a uniform relative risk reduction in both men and women. In high-risk groups such as diabetics, smokers, hypertensives, and the elderly, there were also significant risk reductions in clinical end points. Finally, in the 598 participants, who had a stroke (90% of which were non-fatal), CARE and LIPID individually demonstrated reductions in non-fatal and total stroke. These data confirm that benefits of treatment in secondary prevention of coronary heart disease encompasses prevention of stroke as well as coronary heart disease events. The benefits are found in those who have had unstable angina as well as myocardial infarction. These findings strengthen even further the case for much more widespread use of statins in secondary prevention.

Interim monitoring of clinical trials based on long-term binary endpoints

This paper discusses interim analysis of randomized clinical trials for which the primary endpoint is observed at a specific long-term follow-up time. For such trials subjects only yield direct information on the primary endpoint once they have been followed through to the long-term follow-up time, potentially eliminating a large proportion of the accrued sample from an interim analysis of the primary endpoint. We advocate more efficient interim analysis of long-term endpoints by augmenting long-term information with short-term information on subjects who have not yet been followed through to the long-term follow-up time. While retaining the long-term endpoint as the subject of the analysis, methods of jointly analysing short- and long-term data are discussed for reversible binary endpoints. It is shown theoretically and by simulation that the use of short-term information improves the efficiency with which long-term treatment differences are assessed based on interim data. Sequential analysis of treatment differences is discussed based on spending functions, and is illustrated with a numerical example from a cholesterol treatment trial.

Reduction of stroke events with pravastatin: the Prospective Pravastatin Pooling (PPP) Project

BACKGROUND

Stroke is a leading cause of death and disability. Although clinical trials of the early lipid-lowering therapies did not demonstrate a reduction in the rates of stroke, data from recently completed statin trials strongly suggest benefit.

METHODS AND RESULTS

The effect of pravastatin 40 mg/d on stroke events was investigated in a prospectively defined pooled analysis of 3 large, placebo-controlled, randomized trials that included 19 768 patients with 102 559 person-years of follow-up. In all, 598 participants had a stroke during approximately 5 years of follow-up. The 2 secondary prevention trials (CARE [Cholesterol And Recurrent Events] and LIPID [Long-term Intervention with Pravastatin in Ischemic Disease]) individually demonstrated reductions in nonfatal and total stroke rates. When the 13 173 patients from CARE and LIPID were combined, there was a 22% reduction in total strokes (95% CI 7% to 35%, P:=0.01) and a 25% reduction in nonfatal stroke (95% CI 10% to 38%). The beneficial effect of pravastatin on total stroke was observed across a wide range of patient characteristics. WOSCOPS (West of Scotland Coronary Prevention Study, a primary prevention trial in hypercholesterolemic men) exhibited a similar, although smaller, trend for a reduction in total stroke. Among the CARE/LIPID participants, pravastatin was associated with a 23% reduction in nonhemorrhagic strokes (95% CI 6% to 37%), but there was no statistical treatment group difference in hemorrhagic or unknown type.

CONCLUSIONS

Pravastatin reduced the risk of stroke over a wide range of lipid values among patients with documented coronary disease. This effect was due to a reduction in nonfatal nonhemorrhagic strokes.

Pravastatin and the development of diabetes mellitus: evidence for a protective treatment effect in the West of Scotland Coronary Prevention Study

BACKGROUND

We examined the development of new diabetes mellitus in men aged 45 to 64 years during the West of Scotland Coronary Prevention Study.

METHODS AND RESULTS

Our definition of diabetes mellitus was based on the American Diabetic Association threshold of a blood glucose level of >/=7.0 mmol/L. Subjects who self-reported diabetes at baseline or had a baseline glucose level of >/=7.0 mmol/L were excluded from the analyses. A total of 5974 of the 6595 randomized subjects were included in the analysis, and 139 subjects became diabetic during the study. The baseline predictors of the transition from normal glucose control to diabetes were studied. In the univariate model, body mass index, log triglyceride, log white blood cell count, systolic blood pressure, total and HDL cholesterol, glucose, and randomized treatment assignment to pravastatin were significant predictors. In a multivariate model, body mass index, log triglyceride, glucose, and pravastatin therapy were retained as predictors of diabetes in this cohort.

CONCLUSIONS

We concluded that the assignment to pravastatin therapy resulted in a 30% reduction (P:=0.042) in the hazard of becoming diabetic. By lowering plasma triglyceride levels, pravastatin therapy may favorably influence the development of diabetes, but other explanations, such as the anti-inflammatory properties of this drug in combination with its endothelial effects, cannot be excluded with these analyses.

Use of lipid-lowering medications at discharge in patients with acute myocardial infarction: data from the National Registry of Myocardial Infarction 3

BACKGROUND

The present study aimed to assess use of lipid-lowering medication at discharge in a current national sample of patients hospitalized with acute myocardial infarction and to evaluate factors associated with prescribing patterns.

METHODS AND RESULTS

Demographic, procedural, and discharge medication data were collected from 138 001 patients with acute myocardial infarction discharged from 1470 US hospitals participating in the National Registry of Myocardial Infarction 3 from July 1998 to June 1999. Lipid-lowering medications were part of the discharge regimen in 31. 7%. Among patients with prior history of CAD, revascularization, or diabetes, less than one half of the patients were discharged on treatment. In multivariate analysis, factors independently related to lipid-lowering use included history of hypercholesterolemia (odds ratio [OR] 4.93; 95% CI 4.79 to 5.07), cardiac catheterization during hospitalization (OR 1.29; 95% CI 1.24 to 1.34), care provided at a teaching hospital, (OR 1.26; 95% CI 1.22 to 1.32), use of ss-blocker (OR 1.43; 95% CI 1.39 to 1.48), and smoking cessation counseling (OR 1.51; 95% CI 1.44 to 1.59). Lipid-lowering medications were given less often to patients who were older (65 to 74 versus <55 years of age; OR 0.82; 95% CI 0.78 to 0.86), those with a history of hypertension (OR 0.92; 95% CI 0.89 to 0.95), and those undergoing coronary artery bypass graft surgery (OR 0.58; 95% CI 0.55 to 0.60).

CONCLUSIONS

Analysis of current practice patterns for the use of lipid-lowering medications in patients hospitalized with acute myocardial infarction reveals that a significant proportion of high-risk patients did not receive treatment at time of discharge.

Choices in medical management for prevention of acute ischemic stroke

Stroke is a leading cause of death and disability. Although advances are being made in the treatment of acute ischemic stroke, its prevention is equally as important. Identification and management of risk factors are essential. Medical therapy is also helpful in the secondary prevention of ischemic stroke. There are currently four platelet-antiaggregating agents used to prevent ischemic stroke: aspirin, aspirin plus dipyridamole, clopidogrel, and ticlopidine. The relevant studies proving their efficacy are noted, as are some of their similarities and differences. The use of warfarin is also discussed.

Treating patients with low high-density lipoprotein cholesterol: choices, issues and opportunities

Three clinical trials have recently focused on the benefits of lipid-regulating therapy in populations with normocholesterolaemia and low high-density lipoprotein (HDL)-cholesterol. Two secondary prevention studies (Veterans Affairs HDL-Cholesterol Intervention Trial [VA-HIT] and Bezafibrate Infarction Prevention [BIP] trial) testified to the efficacy of fibrates in decreasing cardiovascular events, particularly in patients with coexisting risk factors, including hypertriglyceridaemia. The Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS) demonstrated that a statin could decrease acute coronary events in patients with isolated low HDL-cholesterol in a primary prevention setting. The absolute risk reduction in coronary events in the VA-HIT study compares favourably with those reported from the statin-based Cholesterol and Recurrent Events (CARE) and Long-term Intervention with Pravastatin in Ischaemic Disease (LIPID) trials. The absolute risk reduction in AFCAPS-TexCAPS is similar to that in West of Scotland Coronary Pravastatin Study (WOSCOPS). Recommendations are given concerning lifestyle and pharmacological management of low HDL-cholesterol. Optimal management also requires review of current treatment targets for HDL-cholesterol and triglycerides levels.

Diabetes in elderly adults

Diabetes is common in the elderly population. By the age of 75, approximately 20% of the population are afflicted with this illness. Diabetes in elderly adults is metabolically distinct from diabetes in younger patient populations, and the approach to therapy needs to be different in this age group. Diabetes is associated with substantial morbidity from macro- and microvascular complications. Several lines of evidence suggest that optimal glycemic control and risk factor modification can substantially reduce the risk of complications in elderly patients. In the past, treatment options were limited. However, recent studies have delineated several new and exciting therapeutic opportunities for elderly patients with diabetes.

Anti-atherogenic effects of fibrates in type 2 diabetes

Type 2 diabetes is an increasing cause of premature coronary heart disease. Several trials with lipid-modifying therapy have included sufficient numbers of diabetics to indicate that treatment of diabetic dyslipidaemia with either fibrates or statins reduces the risk of future coronary events in such patients. However, until recently no reported study had been designed specifically to investigate the effects of intervening in patients with type 2 diabetes. The Diabetes Atherosclerosis Intervention Study (DAIS) is an angiographic study in which 418 diabetic subjects were randomized to micronised fenofibrate or placebo groups. After 3 years of treatment, the fenofibrate group had a significantly reduced rate of progression of coronary atherosclerosis. This study, when considered with the results of other studies that have included diabetics, has important implications for the treatment of diabetic dyslipidaemia. The evidence that is currently available supports a place for both fibrates and statins, either as monotherapy or in combination, in the treatment of diabetic dyslipidaemia.

Statin trials in progress: unanswered questions

Five years ago, many critics questioned the value of lipid-lowering therapy. Today, the clinical benefits of statins are well documented, but the challenge remains to fully implement these benefits across the wide spectrum of the at-risk population, and continue to advance our understanding regarding the potential for the benefits of statins across an even broader range of select patient populations.

Debate: "How low should LDL cholesterol be lowered?" Viewpoint: "It doesn't need to be very low"

The importance of low-density lipoprotein (LDL) control in the management of patients at high risk of cardiovascular events is unquestionable. The major statin trials have shown that the benefits of LDL lowering extend throughout the range of risk and the range of serum cholesterol, and have indicated that the protective effects of the intervention are mostly related to the baseline risk. Statin therapy is, for this reason, currently seen as an anti-atherogenic approach for the majority of high risk individuals and possibly all coronary heart disease patients. This debate is not about the value of statin therapy or the importance of LDL reduction, but about the goals to be set once we decide that LDL cholesterol must be reduced. With the National Cholesterol Education Program (NCEP) guidelines representing a solid middle ground, the two viewpoints in this debate try to argue, on one hand, that the LDL goals should be substantially lower than our current standards or, on the other, that a specific on-treatment LDL value may not be the most important goal to pursue. We defend the latter position by presenting the case that the most effective LDL intervention in high risk patients is to achieve a reduction of at least 30%. This strategy complies with the NCEP guidelines, as most of the high risk patients treated with an average dose of an average statin would experience a 30-40% LDL reduction that would put on-treatment LDL levels safely below goal. Our position differs from both the guidelines and the proponents of more aggressive LDL goals in the management of the two extremes of the cholesterol distribution, where our lack of interest in a predefined on-treatment LDL concentration would make us more aggressive than guidelines on low baseline LDL patients and less aggressive than guidelines on high baseline LDL patients.

Cost-effectiveness analysis of n-3 polyunsaturated fatty acids (PUFA) after myocardial infarction: results from Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto (GISSI)-Prevenzione Trial

OBJECTIVE

To estimate the cost effectiveness of treatment with n-3 polyunsaturated fatty acids (PUFA) for secondary prevention after myocardial infarction (MI).

DESIGN AND SETTING

The cost-effectiveness analysis of n-3 PUFA treatment after MI was based on morbidity and mortality data and the use of resources obtained prospectively during the 3.5 year follow-up period of the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto (GISSI)-Prevenzione study. The cost-effectiveness analysis took into account the incremental number of life-years gained and the incremental costs for hospital admissions, diagnostic tests and drugs, applying a 5% discount rate. The value for money of n-3 PUFA treatment was assessed using the cost-effectiveness ratio and the number needed to treat (NNT) approach.

PERSPECTIVE

Third-party payer.

MAIN OUTCOME MEASURES AND RESULTS

The incremental cost-effectiveness ratio for n-3 PUFA in the basecase scenario was 24,603 euro (EUR, 1999 values) per life-year gained (95% confidence interval: 22,646 to 26,930). Sensitivity analysis included the analysis of extremes, producing estimates varying from EUR15,721 to EUR52,524 per life-year gained. 172 patients would need to be treated per year with n-3 PUFA, at an annual cost of EUR68,000, in order to save 1 patient. This is comparable with the NNT value, and associated annual cost for simvastatin, but less costly than that for pravastatin.

CONCLUSIONS

The cost effectiveness of long term treatment with n-3 PUFA is comparable with other drugs recently introduced in the routine care of secondary prevention after MI. Since the clinical benefit provided by n-3 PUFA is additive, this therapy should be added to the established routine practice, with additive costs.

Pluripotential mechanisms of cardioprotection with HMG-CoA reductase inhibitor therapy

Treatment with hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors has been accompanied by a reduced risk of cardiovascular events. Rapid onset of clinical benefit and weak correlations between plasma low density lipoprotein-cholesterol levels and coronary lumen change or cardiovascular events indicates that nonlipid mechanisms are involved in this beneficial effects with HMG-CoA reductase inhibitors. Furthermore, more rapid onset of clinical benefit with HMG-CoA reductase inhibitors in patients with acute coronary syndromes or acute myocardial infarction than in those with stable coronary heart disease suggest that HMG-CoA reductase inhibitors facilitate repair of ruptured or ulcerated atherosclerotic plaque, facilitate plaque stabilization and/or reduce thrombus formation on ruptured plaques. Treatment with HMG-CoA reductase inhibitors improved endothelial dysfunction in patients with hypercholesterolemia and this improvement in endothelial function was not correlated with reduction in total serum cholesterol levels. Similarly, reduction in endothelial pre-proendothelin mRNA expression and endothelin synthesis and blood pressure lowering with HMG-CoA reductase inhibitors occurred independent of lipid-lowering. Finally, HMG-CoA reductase inhibitors increased endothelial nitric oxide levels i.e. upregulated endothelial nitric oxide synthetase expression via post-transcriptional mechanisms and prevented its down-regulation by oxidized LDL-C. HMG-CoA reductase inhibitors have been shown to modulate the immune response by inhibiting activation of immune-competent cells such as macrophages, and antigen presentation to macrophages by T cells. Treatment with HMG-CoA reductase inhibitors can reduce expression, production and circulating levels of chemokines (monocyte chemoattractant protein-1) and proinflammatory cytokines [tumor necrosis factoralpha, interleukin (IL)-6 and IL-1beta]. HMG-CoA reductase inhibitors reduced inflammation in human atheroma: significantly fewer macrophages and T cells, less oxidized LDL-C and higher collagen content. In addition, treatment with HMG-CoA reductase inhibitor led to decreased cell death within the atheroma. Treatment with these agents also reduced expression of inducible cellular adhesion molecules, decreased secretion of metalloproteinases by macrophages, reduced vascular smooth muscle cell apoptosis. Lastly, HMG-CoA reductase inhibitors appear to have important effects on the thrombogenesis: reduced expression of tissue factor production and activity; increased production of tissue factor package inhibitor; decreased platelet thrombus formation and improved fibrinolysis as a result of lowered plasminogen activator inhibitor-1 levels. As the pluripotential cardioprotective mechanisms of HMG-CoA reductase inhibitors are further elucidated, it is envisaged that treatment with HMG-CoA reductase inhibitors will be initiated earlier and more frequently in patients with hypercholesterolemia.

Debate: Should statin be used in patients with heart failure?

Statins reduce mortality of patients with coronary artery disease (CAD). However, by protocol, trials have excluded patients with chronic heart failure. Since the prevalent etiology of heart failure is CAD, preventing CAD may prevent heart failure progression. Statins may have other beneficial effects besides cholesterol lowering, such as anti-inflammatory properties and improvement of endothelial function. On the contrary, high levels of cholesterol can be beneficial in heart failure patients on the basis of the ability of serum lipoproteins to modulate inflammatory response. Furthermore, statins affecting mitochondrial function can have a deleterious effect on skeletal or cardiac muscles. Despite all these conflicting data, there is no evidence from trials on the effects of statins in patients with heart failure. For this reason, the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI) investigators planned a controlled trial testing the effect of statins in patients with heart failure of different etiology.

Diabetes: statins, fibrates, or both?

Cardiovascular disease is the leading cause of mortality in patients with type 2 diabetes. Among the many factors that are involved in the pathogenesis of atherosclerosis in diabetic patients, dyslipidemia plays a major role. It is characterized by an increase in triglycerides, a decrease in high-density lipoprotein cholesterol and normal or mildly elevated low-density lipoprotein cholesterol. The management of patients with diabetic dyslipidemia is difficult because we lack studies specifically designed for diabetic patients. Thus, strategy has to rely on post hoc analyses of landmark intervention trials, which usually include only a small number of diabetic patients, or on rare trials enrolling small cohorts of diabetic patients. When lifestyle changes fail, monotherapy should be tried first with either a statin or a fibrate, depending on triglyceride level. If lipid target values are not reached, a combination therapy can then be initiated, with close follow-up of potential side effects.

Current perspectives on lipid lowering with statins to decrease risk of cardiovascular disease

Although guidelines for individual risk factors for cardiovascular disease (CVD) assist the healthcare provider, management of the global risk profile of patients is the optimal means to minimize risk. Regardless of whether patients have one or more risk factors, elevated lipid values are generally considered to be a major contributor to global CVD risk. Therefore, reduction of lipid levels is one of the most effective methods to reduce risk of CVD. The 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitor class of drugs (also known as statins) has documented clinical benefits for reducing the incidence of myocardial infarction, stroke, death from CVD, and total death. Despite widespread acknowledgment of the very favorable benefit-to-risk ratio of the statins, most at-risk patients either are not being treated or are not at the goals defined by the National Cholesterol Education Program.

If LDL-C is the answer...what was the question? What do the data really show?

The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are frequently utilized in the treatment of hypercholesterolemia. With recently completed statin clinical cardiovascular outcomes data available, the purpose of this review is to analyze the relative benefits of each molecule and to determine whether "lower is better" is a correct hypothesis for secondary prevention. Twenty-one clinical studies, each with a duration of statin therapy of 6 months or longer, were reviewed, and the pharmacologic effects of these agents on cardiovascular outcomes was examined. As evaluated by study drug, statistical event reduction was achieved in seven of nine pravastatin studies, one of three simvastatin studies, one of six lovastatin studies, zero of two fluvastatin studies, and zero of one atorvastatin study. Pravastatin was the only statin proven statistically to reduce events in both primary and secondary prevention. Thus, all of the statins do not appear to be the same in terms of their ability to reduce cardiovascular events. Until head-to-head trials have been completed, these clinical outcomes data suggest that in patients with severe hypercholesterolemia who require high-dose statin therapy, simvastatin 80 mg each evening would appear to be the agent of choice. However, pravastatin 40 mg daily at bedtime appears to be a unique molecule, with the strongest evidence for event reduction in the majority of patients with moderate hypercholesterolemia with, or who are at risk for, coronary heart disease.

Inflammatory mechanisms

Traditional concepts of the pathogenesis of acute coronary syndromes have changed over the last few years. In particular it has been demonstrated that high-risk lesions are not necessarily angiographically severe. Rather, unstable high risk lesions are the ones composed of large lipid cores and thin fibrous caps. It is now widely accepted that plaque instability is related to the development of inflammation within the intima. A consequence of this is that stabilization of lesions provides a new therapeutic target. Furthermore, there is growing evidence that statins may stabilize lesions by altering the inflammatory response. A brief overview of these developments and their impact on clinical practice is presented.

Pharmacology and clinical experience with simvastatin

Simvastatin (Zocortrade mark, Merck) is a safe and effective 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. Simvastatin potently lowers total and low density lipoprotein (LDL) cholesterol. Simvastatin was the first cholesterol-lowering agent that reduced total mortality in a randomised clinical trial. Simvastatin is effective at reducing total mortality, myocardial infarction, coronary mortality and the incidence of stroke or transient ischemic attack in patients with coronary heart disease and hypercholesterolemia. Simvastatin, like other statins, also has non-lipid mechanisms of action. These include anti-inflammatory effects, antiproliferative effects on smooth muscle cells and an upregulation of endothelial nitric oxide synthase. Overall, simvastatin has an excellent safety profile. Simvastatin, along with other statins, has made a significant impact on the morbidity and mortality from coronary heart disease.

Diabetes

The causes of accelerated atherogenesis in diabetes are unclear but the consequences in terms of cardiovascular morbidity and mortality are profound. Thus diabetes not only increases the risk of coronary heart disease but also increases the case fatality rate, ensuring that the majority of patients die of cardiovascular causes, often before the age of 50 years. The problem is compounded by autonomic neuropathy which alters the perception of cardiac pain, attenuating symptoms which are often atypical or absent. This may delay presentation or lead to inappropriate triage decisions such that access to defibrillators and specific treatment is denied. Central to the cardiovascular management of diabetes is vigorous risk factor modification although clear evidence that this leads to extra protection against coronary heart disease beyond that achieved in non-diabetic individuals has not been forthcoming. In other respects too, the management of diabetic patients with heart disease is underpinned by the same evidence-base as applies to non-diabetic patients, and it is noteworthy that 15-20% of the patients in most of the landmark clinical trials have been diabetic. Recently, however, trials such as the United Kingdom Prospective Diabetes Study (UKPDS), the Heart Outcomes Prevention Evaluation (HOPE) study, and the Diabetes Mellitus, Insulin Glucose Infusion in Acute Myocardial Infarction (DIGAMI) study have identified novel strategies for reducing cardiovascular risk in diabetes. These trials have already had a major impact on cardiological practice, emphasising the prime importance of blood pressure control and converting enzyme inhibition for reducing cardiovascular risk in diabetes as well as the value of insulin therapy for reducing mortality in diabetic myocardial infarction. Additional trials, already in progress, are expected to refine further the cardiovascular management of patients with diabetes in order to provide an effective challenge for a problem that shows no signs of going away.