Trials

http://www.trialsjournal.com/

List of Papers (Total 4,164)

Informative noncompliance in endpoint trials

Noncompliance with study medications is an important issue in the design of endpoint clinical trials. Including noncompliant patient data in an intention-to-treat analysis could seriously decrease study power. Standard methods for calculating sample size account for noncompliance, but all assume that noncompliance is noninformative, i.e., that the risk of discontinuation is...

Current trends in the cardiovascular clinical trial arena (I)

The existence of effective therapies for most cardiovascular disease states, coupled with increased requirements that potential benefits of new drugs be evaluated on clinical rather than surrogate endpoints, makes it increasingly difficult to substantiate any incremental improvements in efficacy that these new drugs might offer. Compounding the problem is the highly controversial...

Anticoagulation for non-valvular atrial aibrillation – towards a new beginning with ximelagatran

Objectives Ximelagatran is a novel oral direct thrombin inhibitor. It has favorable pharmacodynamic properties, with a broad therapeutic range without the need for anticoagulation monitoring. We aimed to discover whether ximelagatran offers a genuine future replacement to warfarin for patients in persistent atrial fibrillation (AF). Materials and methods We provide an evidence...

Unanswered ethical and scientific questions for trials of invasive interventions for coronary disease: The case of single vessel disease

Trials in the 1990s demonstrated that medical therapy is as effective as invasive therapies for treating single-vessel coronary disease. Yet more recent studies enrolling patients with this condition have focused on evaluating only invasive approaches, namely, stenting versus coronary artery bypass surgery. Several ethical and scientific questions remain unanswered regarding the...

A randomized controlled trial of an extensive lifestyle management intervention (ELMI) following cardiac rehabilitation: study design and baseline data

Background Cardiac rehabilitation programs (CRP) represent comprehensive interventions that are typically limited to four months. Following completion of CRP, it appears that risk factors and lifestyle behaviours may deteriorate. The Extensive Lifestyle Management Intervention (ELMI) Following Cardiac Rehabilitation trial will investigate the benefits of a randomized intervention...

A Prospective Study of Pravastatin in the Elderly at Risk (PROSPER): Screening Experience and Baseline Characteristics

Background PROSPER was designed to investigate the benefits of treatment with pravastatin in elderly patients for whom a typical doctor might consider the prescription of statin therapy to be a realistic option. Methods The PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) is a randomised, double blind, placebo-controlled trial to test the hypothesis that...

A Review of the Adverse Effects of Peripheral Alpha-1 Antagonists in Hypertension Therapy

Background Doxazosin and its role as an antihypertensive agent have come under recent scrutiny as a result of the early termination of that treatment arm in ALLHAT. It is unclear why the cardiovascular (CV) event rate in this randomized, controlled trial (RCT), especially heart failure, is higher in those treated with a doxazosin-based regimen than with a chlorthalidone based...

Long-term vitamin E supplementation fails to reduce lipid peroxidation in people at cardiovascular risk: analysis of underlying factors

Background Antioxidant supplementation with vitamin E had no effect in the prevention of cardiovascular diseases (CVD) in three recent large, randomized clinical trials. In order to reassess critically the role of vitamin E in CVD prevention, it is important to establish whether these results are related to a lack of antioxidant action. Methods We examined the in vivo antioxidant...

Pooling, meta-analysis, and the evaluation of drug safety

Background The "integrated safety report" of the drug registration files submitted to health authorities usually summarizes the rates of adverse events observed for a new drug, placebo or active control drugs by pooling the safety data across the trials. Pooling consists of adding the numbers of events observed in a given treatment group across the trials and dividing the results...

Problems in dealing with missing data and informative censoring in clinical trials

A common problem in clinical trials is the missing data that occurs when patients do not complete the study and drop out without further measurements. Missing data cause the usual statistical analysis of complete or all available data to be subject to bias. There are no universally applicable methods for handling missing data. We recommend the following: (1) Report reasons for...

Clinical significance of cardiovascular dysmetabolic syndrome

Although diabetes mellitus is predominantly a metabolic disorder, recent data suggest that it is as much a vascular disorder. Cardiovascular complications are the leading cause of death and disability in patients with diabetes mellitus. A number of recent reports have emphasized that many patients already have atherosclerosis in progression by the time they are diagnosed with...

Weight-modification trials in older adults: what should the outcome measure be?

Background Overweight older adults are often counseled to lose weight, even though there is little evidence of excess mortality in that age group. Overweight and underweight may be more associated with health status than with mortality, but few clinical trials of any kind have been based on maximizing years of healthy life (YHL), as opposed to years of life (YOL). Objective This...

A new era in hypertension research: discussing the findings of ALLHAT

The key question in hypertension research today is, "Does it matter how elevated blood pressure is lowered?" The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) initiated in 1994 serves as a model for comparative trials. Its strengths include its independent sponsorship, scope and design. The alpha-blocker arm was stopped early; doxazosin was...

Debate: PCI vs CABG: a moving target, but we are gaining

The treatment of patients with coronary artery disease continues to evolve; all three strategies – medical therapy, surgical revascularization, and percutaneous coronary intervention – have changed. Medical therapy with intense risk-factor modification and treatment with a statin, aspirin, and angiotensin-converting enzyme (ACE) inhibitors, should be used unless contraindicated...

Debate: Statins should be used in patients with heart failure

Treatment to prevent progression of heart failure has been targeted to reverse the consequences of heart failure and to a lesser extent the cause – the atherosclerotic plaque itself. Less than 50% of patients with heart failure are treated with lipid intervention. Heart failure (New York Heart Association [NYHA] functional classes I and II) is associated with an increase in low...

Biventricular pacing in heart failure: update on results from clinical trials

Biventricular pacing or resynchronisation therapy is a non-pharmacological therapy for patients with chronic heart failure. Since being originally described in 1994, biventricular pacing has become a subject of intense interest and investigation. This review analyses the results reported in observational series and randomised trials, and seeks to answer two questions. If it works...

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...

Distal protection devices during percutaneous coronary and carotid interventions

Distal embolization of particulate matter complicates percutaneous coronary and peripheral interventions more often than had been recognized until recently. A number of distal protection devices are under development. The PercuSurge GuardWire™ is a balloon occlusion thrombectomy device approved by the United States Food and Drug Administration for saphenous vein graft...

Benefits and side effects of blood pressure lowering treatment: what was wrong with doxazosin in the ALLHAT?

The lowering of high blood pressure is supposed to protect target organs from hypertensive damage. The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial was designed to compare the cardioprotective properties of three antihypertensives from different classes (lisinopril, amlodipine and doxazosin) with chlorthalidone. Despite effective blood pressure...

Comments on ALLHAT and doxazosin

This commentary has two purposes: to summarize the rationale, design and initial results of the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) trial; and to provide a history of the response to ALLHAT that led to a civil action and a Citizens Petition that was the basis for a public hearing by the US Food and Drug Administration, in May 2001...

Debate: PCI or CABG for multivessel disease? Viewpoint: No clear winner in an unfair fight

The Arterial Revascularization Therapy Study (ARTS) and the Stent or Surgery (SoS) trial each randomized patients with multivessel disease to either stenting or bypass surgery. The ARTS showed no difference in mortality between the two strategies, other than in diabetic patients, who fared better with surgery. The SoS trial demonstrated increased mortality in the stent arm, a...

Therapeutic angiogenesis for cardiovascular disease

The identification of angiogenic growth factors, such as vascular endothelial growth factor and fibroblast growth factor, has fueled interest in using such factors to induce therapeutic angiogenesis. The results of numerous animal studies and clinical trials have offered promise for new treatment strategies for various ischemic diseases. Increased understanding of the cellular...

How well can blood pressure be controlled? Progress report on the Systolic Hypertension in Europe Follow-Up Study (Syst-Eur 2)

Background The randomised, double-blind, placebo-controlled Systolic Hypertension in Europe trial (Syst-Eur 1) proved that blood pressure (BP) lowering therapy starting with nitrendipine reduces the risk of cardiovascular complications in elderly patients with isolated systolic hypertension. In an attempt to confirm the safety of long-term antihypertensive therapy based on a...

Cytokines as new treatment targets in chronic heart failure

Inflammatory cytokines may negatively influence contractility and contribute to the remodelling process in the failing myocardium. Traditional cardiovascular drugs appear to have little influence on the overall cytokine network in chronic heart failure (CHF). Increased interest in anticytokine therapy has therefore evolved. Several small studies have used tumour necrosis factor...

Withdrawal of cerivastatin from the world market

Cerivastatin was recently withdrawn from the market because of 52 deaths attributed to drug-related rhabdomyolysis that lead to kidney failure. The risk was found to be higher among patients who received the full dose (0.8 mg/day) and those who received gemfibrozil concomitantly. Rhabdomyolysis was 10 times more common with cerivastatin than the other five approved statins. We...