Clinical development of antiepileptic drugs in adults

Over the last two decades, ten so-called newer antiepileptic drugs (AEDs) have been approved around the world, the majority of which have found and maintained a place in the seizure-fighting armamentarium for the whole spectrum of epilepsies and epileptic syndromes; some of these drugs have features that are improved compared with the older drugs. Within that same time period, the process of clinical development of AEDs has also undergone changes and has become much more complex and costly. Efforts are underway to shift decision-making about the clinical viability of AED candidates to earlier development stages, using the concept of translational medicine. However, thus far all of the newer AEDs have undergone a standard development as an adjunct in the control of adult partial seizures; in some cases, development has been expanded to other seizure types and pediatric syndromes. Currently, the path to global approval for use in monotherapy is under review and is often debated with regulatory authorities. Clinical treatment guidelines consider randomized, blinded, well controlled studies as the premier level of evidence-based medicine; these studies originate mostly in confirmatory phases of the development program. However, with the rigid designs and criteria in regulatory driven trials, effectiveness in the clinical practice setting may not be sufficiently predicted by these studies, leading to frustrations from individual practitioners. Finally, additional safety issues regularly occur only after the postlaunch exposure to a broader population making necessary a continuing, and thorough, pharmacovigilance after the AED has come to market.

Impact on hypertension control of a patient-held guideline: a randomised controlled trial

BACKGROUND

Hypertension is generally poorly controlled in primary care. One possible intervention for improving control is the harnessing of patient expertise through education and encouragement to challenge their care.

AIM

To determine whether encouraging patients to manage their hypertension in an 'expert' manner, by providing them with information in a clear clinical guideline, coupled with an explicit exhortation to become involved in and to challenge their own care if appropriate, would improve their care.

DESIGN OF STUDY

Single blind randomised controlled trial of detailed guideline versus standard information.

SETTING

Single urban general practice over 1 year.

METHOD

Patient-held guideline with written explicit exhortation to challenge care when appropriate. Two hundred and ninety-four of 536 eligible patients on the practice hypertension register were recruited, all of whom were randomised into one of two groups. Two hundred and thirty-six patients completed the study.

RESULTS

PRIMARY OUTCOME

average systolic blood pressure.

SECONDARY OUTCOMES

proportion of patients with blood pressure < 150 mmHg systolic and < 90 mmHg diastolic, average cholesterol, proportion of patients prescribed statins and aspirin according to guideline, hospital anxiety and depression score. No clinically, or statistically significant differences were found between intervention and control with respect to all parameters or in anxiety and depression levels. Statin and aspirin use improved throughout the course of the study in both groups. Statin use showed a trend (P = 0.02) in favour of control.

CONCLUSION

In this study there was no clinically significant perceived benefit to patients as a result of providing them with a hypertension guideline. Patient guidelines are currently planned for many chronic illnesses. It is important to determine the utility of such interventions before scarce resources are applied to them.

Epigenetic regulation of immune escape genes in cancer

According to the concept of immune surveillance, the appearance of a tumor indicates that it has earlier evaded host defenses and subsequently must have escaped immunity to evolve into a full-blown cancer. Tumor escape mechanisms have focused mainly on mutations of immune and apoptotic pathway genes. However, data obtained over the past few years suggest that epigenetic silencing in cancer may be as frequent a cause of gene inactivation as are mutations. Here, we discuss the evidence that tumor immune evasion is mediated by non-mutational epigenetic events involving chromatin and that epigenetics collaborates with mutations in determining tumor progression. Since epigenetic changes are potentially reversible, the relative contribution of mutations and epigenetics, to the gene defects in any given tumor, may be a factor in determining the efficacy of treatments. We review new developments in basic chromatin mechanisms and in this context describe the rationale for the current use of epigenetic agents in cancer therapy and for a novel epigenetically generated tumor vaccine model. We emphasize that epigenetic cancer treatments are currently a 'blunt-sword' and suggest future directions for designing chromatin-based programs of potential value in the diagnosis and treatment of cancer.

Co-ordinating 'ethical' clinical trials: the role of research coordinators in the contract research industry

Change in the way new drugs are developed, including the privatisation of clinical trials, has altered the arrangement and roles of healthcare professions. In this paper I examine one aspect of this change: the role of research coordinators in the conduct of contract research in the United States. My focus on coordinators highlights the ethical conflicts embedded in clinical trials. I describe the ways in which coordinators experience and contend with the conflict between research and care and show how their construction of ethics is distinct from institutional conceptions formally associated with human subjects research. My analysis demonstrates how the coordinators' focus on ethics is a response to their role conflict and an attempt to reinsert individualised care into the context of research.

Topiramate in the prevention of migraine: a review of its efficacy, tolerability, and acceptability

This paper reviews the results of placebo-controlled trials on topiramate (TPM) in the prophylaxis of migraine, focusing particularly on efficacy and tolerability of the target dose (100 mg/day). Data from well-conducted trials and analyses of pooled data show that TPM is effective against migraine, confirming the experience of physicians in various countries. High responder rate and good tolerability following slow titration suggest TPM as a first-line option for migraine prophylaxis. Patient acceptability may be enhanced by lack of weight gain, lack of major contraindications, and positive effects on quality of life.

Epigallocatechin-3-gallate (EGCG): chemical and biomedical perspectives

The compound (-)-epigallocatechin-3-gallate (EGCG) is the major catechin found in green tea [Camellia sinensis L. Ktze. (Theaceae)]. This polyphenolic compound and several related catechins are believed to be responsible for the health benefits associated with the consumption of green tea. The potential health benefits ascribed to green tea and EGCG include antioxidant effects, cancer chemoprevention, improving cardiovascular health, enhancing weight loss, protecting the skin from the damage caused by ionizing radiation, and others. The compound EGCG has been shown to regulate dozens of disease-specific molecular targets. Many of these molecular targets are only affected by concentrations of EGCG that are far above the levels achieved by either drinking green tea or consuming moderate doses of green tea extract-based dietary supplements. In spite of this, well-designed double-blinded controlled clinical studies have recently demonstrated the efficacy of green tea extracts and purified EGCG products in patients. Therefore, this review highlights results from what the authors believe to be some of the most clinically significant recent studies and describes current developments in the stereoselective total synthesis of EGCG.

Declines in number of tender and swollen joints in patients with rheumatoid arthritis seen in standard care in 1985 versus 2001: possible considerations for revision of inclusion criteria for clinical trials

OBJECTIVE

To analyse tender and swollen joint counts in three cohorts of patients with rheumatoid arthritis (RA), with a focus on the proportions of patients who had fewer than 6-12 tender or swollen joints, as possible evidence based information toward more generalisable inclusion criteria for current and future RA clinical trials.

METHODS

Tender and swollen joint counts were analysed in three cohorts of patients with RA: 125 in 1985, 138 in 2000, and 232 with early RA in 2001.

RESULTS

The median numbers of tender joints were 11, 2, and 4 in 1985, 2000, and in early RA in 2001, respectively. The median numbers of swollen joints were 12, 6, and 5 in 1985, 2000, and 2001, respectively. The numbers of tender joints among 28 assessed were >or=12, >or=6, >or=4, and >or=3 in 47%, 80%, 85%, and 90% of patients in 1985; 20%, 37%, 44%, and 49% in 2000; and 17%, 37%, 50%, and 58% in early RA in 2001. The numbers of swollen joints among 28 assessed were >or=12, >or=6, >or=4, and >or=3 in 51%, 78%, 86%, and 90% of patients in 1985; 20%, 50%, 64%, and 67% in 2000; and 14%, 46%, 58%, and 72% in 2001. The number of patients with >or=6 tender or swollen joints in 1985 was greater than the number with >or=3 joints in 2000 and in early RA in 2001.

CONCLUSION

Contemporary cohorts of patients seen in standard care have smaller numbers of tender and swollen joints than in previous times. These findings suggest that revision of inclusion criteria for numbers of tender and swollen joints in contemporary RA clinical trials might improve generalisability.

Improving children's medicines

Perspective on the paper by McLay et al (see page 584)

Drug development in oncology: classical cytotoxics and molecularly targeted agents

There is an apparent need to improve the speed and efficiency of oncological drug development. Furthermore, strategies traditionally applied to the development of standard cytotoxic chemotherapy may not be appropriate for molecularly targeted agents. This is particularly the case for exploratory Phase 1 and 2 trials. Conventional approaches to determine dose based on maximum tolerability and efficacy based on objective tumour response may not be suitable for targeted agents, since many of them have a wide therapeutic index and inhibit tumour growth without demonstrable cytotoxicity. Instead, exploratory trials of targeted agents may have to focus on other end-points such as pharmacological effects and disease stabilization. Thus, there is an increasing interest in making the best possible use of biomarkers and pharmacogenomics in early phases of drug development.

Partnership as an ethical model for medical research in developing countries: the example of the "implementation trial"

The existing model for ethical review of medical research consists primarily of regulations designed to prevent exploitation of participants. This model may fail when reviewing other ethical obligations, particularly the responsibility to provide valuable knowledge to society. Such failure is most apparent in developing countries, in which many stakeholders lack incentives or power to uphold society's interests. An alternative ethical model is that of partnership, which actively involves all partners during ethical review and aims to secure partners' best interests through compromise. Unlike the existing "regulatory" model, the partnership model effectively addresses ethical obligations to provide positive benefits to society. For the partnership model to be effective, power must be shared among partners; thus, the partnership model can be harmonised with the "regulatory" model through explicit consideration of power structures. One opportunity for crafting power balance in developing countries is apparent in "implementation trials"-randomised trials motivated by and integrated into the implementation of long term public health interventions. Given the failings of the existing ethical review model, alternative models-for example, partnership-and means to balance power-for example, implementation trials-must be explored to ensure that medical research provides knowledge of value to societies in the developing world.

Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-Part 2

The herbalist has access to hundreds of years of observational data on the anticancer activity of many herbs. Laboratory studies are expanding the clinical knowledge that is already documented in traditional texts. The herbs that are traditionally used for anti-cancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclo-oxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies or reducing toxicity. Their effectiveness may be increased when multiple agents are used in optimal combinations. New designs for trials to demonstrate activity in human subjects are required. Although controlled trials may be preferable, smaller studies with appropriate endpoints and surrogate markers for anti-angiogenic response could help to prioritize agents for larger, resource-intensive phase iii trials.

Strategies to minimize risks and exploitation in phase one trials on healthy subjects

Most of the literature on phase one trials has focused on ethical and safety issues in research on patients with advanced cancer, but this article focuses on healthy, adult subjects. The article makes six specific recommendations for protecting the rights and welfare of healthy subjects in phase one trials: 1) because phase one trials are short in duration (usually 1 to 3 months), researchers should gather more data on the short-term and long-term risks of participation in phase one studies by healthy subjects; 2) researchers should develop strict inclusion/exclusion criteria that exclude unhealthy or vulnerable subjects, such as decisionally impaired people, in phase one studies; 3) subjects should not participate in more than one phase one study at the same time and should wait at least 30 days between participating in different studies; 4) researchers should develop a database to keep track of phase one participants; 5) subjects should be guaranteed a minimum wage equivalent to the equivalent type of unskilled labor, but there should be no upper limits on wages; and 6) subjects should be allowed to engage in collective bargaining with research sponsors.

Nonepileptic seizures treatment workshop summary

In May 2005, an international, interdisciplinary group of researchers gathered in Bethesda, MD, USA, for a workshop to discuss the development of treatments for patients with nonepileptic seizures (NES). Specific subgroup topics that were covered included: pediatric NES; presenting the diagnosis of NES, outcome measures for NES trials; classification of NES subtypes; and pharmacological treatment approaches and psychotherapies. The intent was to develop specific research strategies that can be expanded to involve a large segment of the epilepsy and psychiatric treatment communities. Various projects have resulted from the workshop, including the initial development of a prospective randomized clinical trial for NES.

Clinical trials in mild cognitive impairment: lessons for the future

Mild cognitive impairment (MCI) is an operational definition for a cognitive decline in individuals with a greater risk of developing dementia. The amnestic subtype of MCI is of particular interest because these individuals most likely progress to Alzheimer's disease (AD). Currently hypothesised therapeutic approaches in MCI are mainly based on AD treatment strategies. Long term secondary prevention randomised clinical trials have been completed in amnestic MCI populations, encompassing agents with various mechanisms of action: acetylcholinesterase inhibitors (donepezil, rivastigmine, galantamine), antioxidants (vitamin E), anti-inflammatories (rofecoxib), and nootropics (piracetam). The design of clinical trials in MCI is influenced by study objectives and definition of primary end points: time to clinical diagnosis of dementia, and AD in particular, or symptom progression. As none of the drugs previously shown to have clinical efficacy in AD trials or benefit in everyday practice have met the primary objectives of the respective trials, design of future clinical trials in MCI should be further developed particularly as regards the selection of more homogeneous samples at entry, optimal treatment duration, and multidimensional and reliable outcomes.

Ethical guideposts to clinical trials in oncology

Clinical research with human subjects is an ethically challenging task requiring ultimate trust on the part of patients and ultimate respect for persons on the part of clinical researchers. The author provides a simple framework to help researchers ensure the ethical integrity of a clinical trial in oncology.

What race and ethnicity measure in pharmacologic research

Advances in genomic technology have put the utility of collecting racial and ethnic data into question. Some researchers are optimistic about the potential of moving toward "personalized medicine" by using a person's genome to administer medications. Genetics will not erase the importance of race and ethnicity because race and ethnicity do not measure genetic composition. Unlike genes, race and ethnicity are social constructs; 2 persons with identical genetic makeup may self-identify as being of different race or ethnic origin. Race and ethnic categories have been subject to change over time; a person's self-identification may vary according to the context, wording, and format of the question asked. Despite the fluid nature of the concept, self-identified race and ethnicity can capture something that genes cannot, namely, aspects of culture, behavior, diet, environment, and features of social status that commonly used measures of socioeconomic status, such as income, education, and occupation, cannot measure.

Treating Alzheimer's disease: do clinical trial methods produce unnecessary practitioner dilemmas?

Recent clinical trials and critical reviews of Alzheimer's disease (AD) research discourage already relatively sparing clinical uses of cholinesterase inhibitors (ChEIs) considering the prevalence of AD. As evidence against use of this class of drugs, detractors cite critical reviews of ChEIs and lack of long-term health benefits found in one long-term clinical trial. This paper describes the use of standard error of measurement to allow investigators to design clinical trials that address these issues. The new clinical trial procedures afford sufficient precision for two purposes. First, practitioners can assess individual patients with precision and certainty in their observations. Second, clinical trial researchers can study how short-term drug effects on individual patients predict long-term benefits from continued treatment. With these more clinically informative clinical trial designs, investigators would be able to avoid uncertainties currently raised by conflicts between short- and long-term AD clinical trials.

Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-Part 1

An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies.

Biomarkers for development of cancer vaccines

The search for molecules that correlate with cancer progression is an evolving and exciting area of research. Such biomarkers have utility in a number of areas, most notably in a variety of clinical development programs. Modern technologies are revealing multiple potential biomarker candidates. However, the challenge remains in validating the correlation in levels of a particular molecule with clinical parameters. In this article, the area of biomarkers and cancer vaccines is briefly reviewed and the possibility of combining multiple molecules to generate a profile that correlates with outcome, rather than using more conventional single molecule biomarker systems, is explored.

Antimicrobial drug resistance, regulation, and research

Innovative regulatory and legislative measures to stimulate and facilitate the development of new antimicrobial drugs are needed. We discuss research approaches that can aid regulatory decision making on the treatment of resistant infections and minimization of resistance selection. We also outline current and future measures that regulatory agencies may employ to help control resistance and promote drug development. Pharmacokinetic/pharmacodynamic research models offer promising approaches to define the determinants of resistance selection and drug doses that optimize efficacy and reduce resistance selection. Internationally, variations exist in how regulators use drug scheduling, subsidy restrictions, central directives, educational guidelines, amendments to prescribing information, and indication review. Recent consultations and collaborations between regulators, academics, and industry are welcome. Efforts to coordinate regulatory measures would benefit from greater levels of international dialogue.

On the Acquisition of Periodontopathic Bacteria by Children from Mothers: A Randomized Double-Masked Placebo-Controlled Trial in Bauru, Brazil

OBJECTIVE: The purpose of this study was two-fold: 1) to determine the effects of mechanical and chemical modalities treatments on periodontal clinical and microbiological parameters of mothers; and 2) to determine the subsequent colonization of periodontal pathogens in tongue samples from their infants. DESIGN: A total of 168 mothers met inclusion criteria to participate in a randomized double-masked placebo-controlled clinical trial. Of those, 121 mothers (and their infants) of 158 seen at baseline provided complete data during study protocols from when their infants were 3 months old until the infants were about 2 years old. Treatments consisted of a combination of xylitol chewing gum, fluoride and chlorhexidine varnishes. The control/placebo group received sorbitol chewing gum and placebo varnishes. The effect of these treatments on periodontal clinical and microbiological parameters of mothers and on microbiological parameters of their infants was assessed by generalized estimating equation models. RESULTS: Microbiological outcomes using the BANA Test were lower for the majority of the visits in the test group when compared to the control/placebo group. These differences, however, were not statistically significant. Similarly, mean PBS results were lower for all follow-up visits for test-group mothers when compared to the control/placebo group's mothers, but of no statistical significance. Colonization of the tongue in infants by periodontal pathogens as measured by the BANA Test showed no distinct patterns concerning the stability of colonization of periodontal pathogens throughout the study period, albeit slightly superior for the test group. CONCLUSIONS: We have demonstrated that a combined chemical modalities treatment consisting of xylitol chewing gum, fluoride varnish and chlorhexidine varnish was moderately superior to control/placebo treatments on periodontal clinical and microbiological parameters of mothers throughout the study period, but of no statistical significance. Similar results were found for the infants in the test group when compared to infants of the control/placebo groups.

Meta-consent in research on decisional capacity: a "Catch-22"?

Empirical studies of ethical issues, which have increased in number and scope in recent years, may themselves raise both practical and ethical issues. One example of such an issue is the question of who may be legitimately enrolled in studies of decision-making capacity; must all participants in studies of consent capacity have capacity to consent? This question may pose a "Catch-22": For example, if some of the participants in a study of consent capacity are deemed by a particular standard to be incapable of consent. In weighing the risks and benefits of studies of consent capacity, how should reviewers consider the context of actual versus hypothetical trials for which the participant's consent is being sought? Here, we explore these "meta-consent" issues by describing the dimensions of the issue and potential solutions, centering around the concept of "active assent" (requiring expressed understanding of the purpose of the study and its voluntary nature, as well as expression of a choice to participate).

Ecological momentary assessment: what it is and why it is a method of the future in clinical psychopharmacology

Current methods of assessment in clinical psychopharmacology have several serious disadvantages, particularly for the study of social functioning. We aimed to review the strengths and weaknesses of current methods used in clinical psychopharmacology and to compare them with a group of methods, developed by personality/social psychologists, termed ecological momentary assessment (EMA), which permit the research participant to report on symptoms, affect and behaviour close in time to experience and which sample many events or time periods. EMA has a number of advantages over more traditional methods for the assessment of patients in clinical psychopharmacological studies. It can both complement and, in part, replace existing methods. EMA methods will permit more sensitive assessments and will enable more wide-ranging and detailed measurements of mood and behaviour. These types of methods should be adopted more widely by clinical psychopharmacology researchers.

Does naltrexone treatment lead to depression? Findings from a randomized controlled trial in subjects with opioid dependence

OBJECTIVE

Dysphoria and depression have been cited as side effects of the opioid antagonist naltrexone. We aimed to assess whether depressive symptoms are a clinically relevant side effect in a population receiving naltrexone as a treatment for opioid dependence.

METHODS

We carried out a randomized controlled, open-label trial comparing rapid opiate detoxification under anesthesia and naltrexone treatment with continued methadone maintenance at the Alcohol and Drug Service, Royal Brisbane and Women's Hospital, Brisbane, Australia. The study subjects were patients stabilized on methadone maintenance treatment for heroin dependence who wished to transfer to naltrexone treatment. The Beck Depression Inventory, State-Trait Anxiety Inventory and Opiate Treatment Index subscales for heroin use and social functioning were used at baseline and follow-up assessments at 1, 2, 3 and 6 months.

RESULTS

Forty-two participants were allocated to receive naltrexone treatment, whereas 38 continued methadone maintenance as the control condition. Participants who received naltrexone did not exhibit worsening of depressive symptoms. In participants attending all follow-up assessments, there was a trend for those receiving naltrexone to exhibit an improvement in depression over time compared with the control group. Participants who were adherent to naltrexone treatment exhibited fewer depressive symptoms than those who were nonadherent.

CONCLUSIONS

These results suggest that depression need not be considered a common adverse effect of naltrexone treatment or a treatment contraindication and that engaging with or adhering to naltrexone treatment may be associated with fewer depressive symptoms.

Understanding of placebo controls among older people with schizophrenia

Research protocols frequently necessitate procedures or design elements that differ from those used in routine clinical care. An example is the inclusion of a placebo arm in many randomized clinical trials. Because there are risks to taking a placebo when one has a chronic disorder such as schizophrenia, ascertaining how well people with severe mental illness understand placebos is an important task for empirical research ethics. We investigated whether schizophrenia patients' understanding of placebo controls could be improved with a brief educational intervention. We randomized 49 middle-aged and older patients with schizophrenia or schizoaffective disorder to receive either (1) a routine explanation of placebos in the context of consent for a hypothetical double-blind placebo-controlled clinical trial, or (2) the consent for the hypothetical trial plus a brief educational module explaining placebos in more depth. Understanding of placebos was assessed with a 12-item questionnaire, and we examined demographic, clinical, neurocognitive, and decision-making correlates of understanding of placebos. Those participants who received the intervention obtained higher scores on the placebo post-test compared to those who received the standard information alone. Performance on the placebo post-test was positively correlated with measures of decisional capacity and neurocognitive abilities and negatively correlated with severity of negative symptoms, but it showed no relationship with positive or general symptoms. Some participants interpreted the common phrase "sugar pill" as relating somehow to diabetes. We conclude that the level of understanding of important research design-related information is not static but may be influenced by how investigators approach the consent process.

Compliance with Xylitol and Sorbitol Chewing Gum Regimens in Clinical Trials

OBJECTIVE: The purpose of this study was to investigate compliance of long-term xylitol and sorbitol chewing gum regimens in adult women participating in a double-blind randomized controlled clinical trial. DESIGN: The participants included 122 mothers (age range: 16-35 years) residing in the city of Bauru, São Paulo, Brazil. Compliance with the xylitol and sorbitol chewing gum regimens was assessed by weighing, with a precision balance, all used gums returned in zip-lock bags during the study period of 33 months. The total number of returned bags in both chewing gum groups was computed and the differences between groups were determined by one-way ANOVA. Compliance was further categorized into excellent, good, fair or poor based on the distribution of the combined data for both groups by quartiles. These distributions for the xylitol and sorbitol groups were subjected to chi-square analysis. RESULTS: Compliance was always superior for the xylitol group in all categories. These distributions were, however, not significantly different in statistical terms. Average compliance in the xylitol chewing gum group was significantly higher when compared to the sorbitol chewing gum group (p=0.0481). CONCLUSIONS: The results suggest that compliance, and possibly acceptance in this population, was superior for xylitol chewing gum than for sorbitol chewing gum.

Recruitment of African American and white postmenopausal women into clinical trials: the beneficial effects of soy trial experience

OBJECTIVE

To describe the strategies and costs associated with recruiting both African American and White postmenopausal women into a randomized controlled trial.

DESIGN

The Beneficial Effects of Soy Trial (BEST) was a randomized, controlled trial designed to determine the effects of a dietary soy supplement on lipoproteins, lipoprotein subclasses, and menopausal symptoms in African American and White postmenopausal women. The goal was to have > or = 80 African American and > or = 80 White women complete the study.

RESULTS

A total of 705 postmenopausal women (381 African American, 324 White) were screened, and of those, 217 were randomized (105 African American, 112 White), and 192 (91 African American, 101 White) completed the study. Direct mailings to targeted zip codes proved the most successful recruitment strategy for recruiting African Americans (52% of African Americans recruited) and the second most effective for recruiting Whites (32% of Whites recruited). Newspaper advertisements yielded the highest number of White participants (36%) but proved less successful for recruiting African Americans (8%). Airing advertisements on the radio was the second most effective strategy for recruiting African Americans (15%), yet it was one of the least effective approaches for recruiting Whites (5%). The total cost of recruitment was dollar 49,036.25, which averaged dollar 255.40 per participant who completed the study. The three most successful strategies, direct mailings, newspaper ads, and radio ads, were the three most expensive approaches but yielded 73% of all participants who completed the study.

Emerging empirical evidence on the ethics of schizophrenia research

Many challenging ethical questions come with the scientific efforts to understand the nature and treatment of schizophrenia. The empirical study of ethical aspects of schizophrenia research has sought to clarify and resolve many of these questions. In this article we provide an overview of the existing data-based literature on schizophrenia research ethics and outline directions for future inquiry. We examine 5 broad categories of inquiry into the ethics of schizophrenia research: (1) Scientific designs (eg, placebo-controlled studies and medication-free intervals, prodromal and high-risk research, and genetics research); (2) informed consent and decision-making capacity, including assessment of decisional abilities, as well as intervention studies; (3) understanding and perceptions of risk and benefit (including the therapeutic misconception); (4) influences on research participation (including voluntarism, altruism, and other motivations); and (5) key participant safeguards, such as protocol review and participant advocates. We discuss how empirical work in each of these areas answers certain questions and raises new ones. Finally, we highlight important gaps in our understanding of ethically relevant aspects of schizophrenia research and offer a specific research agenda for empirical ethics.

The results of the Swiss observational study of the new, fast-dissolving mirtazapine formulation in depressed patients

Objective. The purpose of the present study was to document the experience with the use of a new, fast-dissolving oral tablet (FDT, RemeronSolTab®) of mirtazapine, a NaSSA antidepressant, in the treatment of depressed patients in daily practice in Switzerland. Methods. It was an open, prospective collection of observations in a total of 1121 depressive patients (>18 years old, both sexes). The treatment duration was 8 weeks with assessments after the second and eighth week. Efficacy measures were CGI (seven points) and specific check-lists for the ratings of severity of anxiety and sleep disturbances. At the end of the trial the acceptance (eight-item questionnaire) of the new formulation was recorded too. Results. The results showed that there was highly significant (P<0.001) and rapid improvement of severity of depression, anxiety and sleep disturbances in the whole population. Subgroup analyses showed that the antidepressant efficacy was independent of gender, initial severity of depression or of the type of depression (first episode, recurrent, chronic depression). The majority of patients (80%) liked at least one of the properties of FDT and, out of 75% of patients having experience with conventional tablet, 50% stated to be better compliant with this new formulation. Conclusion. This report documents the antidepressant efficacy of mirtazapine FDT. The new formulation found good acceptance by the patients. The results also suggest a likelihood of improved compliance with the mirtazapine FDT.

A population-based study

BACKGROUND

The last 5 years of trial data demonstrate the ineffectiveness of hormone replacement therapy (HRT). The impact of these trials on age-specific HRT use, HRT discontinuation, and regional HRT variation has not been evaluated extensively.

OBJECTIVE

To characterize the relation between HRT trial dissemination and age-specific HRT use, HRT discontinuation, and regional HRT variation before and after the trials' publication.

DESIGN

Using the Medco Health database, we analyzed HRT prescription filling, discontinuation, and regional variation among women > or =55 years from May 1998 to May 2003.

MEASUREMENTS AND MAIN RESULTS

Approximately 340,000 women were eligible for Medco benefits each month. Within 3 months of the Women's Health Initiative (WHI), HRT prescriptions declined from 12.5% to 9.4%, P< or =.0001. When stratified by age, a statistically significant decline in HRT post-WHI occurred in all age groups, with the biggest decline among women > or =55 to 64 (18% to 11%, P< or =.0001). Among HRT users, we found statistically significant increases in discontinuation in 2002 (67%) compared with 2001 (53%, P<.0001). Prior to the WHI there was substantial regional variation in HRT use, with the West South Central and mid-Atlantic having the highest and lowest proportions, respectively (19% vs 6%, P< or =.0001). Despite a relative decline in HRT use of 25% to 42% across all regions, substantial geographic variation remained.

CONCLUSIONS

Hormone replacement therapy use decreased significantly immediately post-WHI, suggesting that trial results can have a rapid effect on practice. Marked regional variation in HRT use persisted after the WHI, suggesting that local practice patterns exert a strong effect on clinical behavior even after new evidence is available.

The benefits of statin therapy--what questions remain?

Early hydroxymethylglutaryl-CoA reductase inhibitor (statin) trials provided the first evidence of the benefits of statin therapy in secondary prevention of coronary heart disease (CHD). Outcomes data from more recent trials involving atorvastatin, fluvastatin, lovastatin, pravastatin, and simvastatin, have since expanded the patient population shown to benefit from statin therapy. Current studies are evaluating the benefits of lowering lipid levels with statins to below current goals, as well as examining benefits in special patient populations and evaluating the value of surrogate markers of CHD. Early trials provided a solid foundation of knowledge on the efficacy and safety of statins. Recent and ongoing trials generate new data to resolve remaining questions in the fields of CHD prevention and lipidology.

The true treatment benefit is unpredictable in clinical trials using surrogate outcome measured with diagnostic tests

BACKGROUND AND OBJECTIVES

Clinical trials increasingly use results of diagnostic tests as surrogate outcomes. Our objective was to answer the following questions: (1) is the parameter measured by the reference standard a valid surrogate? (2) How does the tests accuracy influence the estimate of the treatment benefit on surrogate? (3) Is it possible to correct the measured treatment effect given by results of inaccurate tests?

METHODS AND SETTING

We reviewed the literature on asymptomatic deep venous thrombosis (DVT), detected by the reference standard and other imaging techniques, as surrogate for venous thromboembolism. The influence of test inaccuracy on the measurement of treatment benefit was calculated as a function of the patient baseline risk, the treatment effect model, and test performances.

RESULTS

We show that: (1) asymptomatic DVT is correlated with clinical outcomes but is yet to be established as a surrogate; (2) inaccurate diagnostic test underestimates the treatment effect on surrogate; (3) the prevalence of the disease, the treatment effect model, and the accuracy of the test and the reference standard used to evaluate it need to be known to correct this underestimation.

CONCLUSION

Even when the surrogate end point is valid, without a reliable study of the diagnostic test we cannot quantify the true treatment effect.

Relationship of the implantable cardioverter defibrillator and chronic resynchronization therapy: the perfect marriage?

BACKGROUND

The two major modes of death in the patient with a reduced ejection fraction (EF) are death due to heart failure and death due to lethal arrhythmia, essentially the two sides of the same coin. Over the last 20 years, two therapies-cardiac resynchronization therapy (CRT) and the implantable cardioverter defibrillator (ICD)-have been developed and tested in clinical trials. They are now, in conjunction with appropriate medical therapy, the mainstays of therapy for these two commonly encountered clinical problems.

METHOD AND RESULTS

Both of these therapies were conceived and patented by two Baltimore cardiologists, Michel Mirowski and Morton Mower (Table I). The path to everyday acceptance of both therapies was remarkably similar. The concept and early success of both devices was accomplished but the proof of concept depended on a series of carefully designed randomized clinical trials that showed that both the CRT and ICD devices saved lives in the low EF population, especially when used together. These trials overcame substantial skepticism on behalf of elements of the cardiology and electrophysiology establishment.

CONCLUSION

We are now at a crossroads in the further extension of either therapy. The majority of the indications for either device alone or in combination are established. In the next few years, assuming the continued commitment on the part of regulatory agencies to fully embrace evidence-based medicine, we will see indications extended but only by the careful clinical trials that became the bedrock of their initial acceptance.

Socio-behaviour challenges to phase III HIV vaccine trials in Sub-Saharan Africa

BACKGROUND

A number of countries in sub-Saharan Africa are preparing for HIV vaccine efficacy trials. Social and behavioural factors related to HIV transmission require examination in each setting where these trials are considered. As part of this, several countries have also recently begun preparatory research investigating relevant social and behavioural issues. There is a need for a review of the literature to help focus such research efforts in Sub-Saharan Africa.

OBJECTIVES

To examine key social and behavioural issues that may impact on the conduct of HIV vaccine efficacy trials in sub-Saharan Africa.

DESIGN

Literature review

METHODS

Major databases (PubMed, PsychInfo, EBSCOhost, and AIDSline) were searched for literature that discussed social and behavioural issues related to HIV vaccine trials. Three areas are highlighted as being particularly significant for HIV vaccine research: (1) willingness to participate in future HIV vaccine efficacy trials, (2) retention of participants in studies, and (3) sexual risk reporting during trials. For each of these topics, major findings from both developed and developing countries are described and avenues for further research are discussed.

RESULTS

There are few data from Sub-Saharan Africa regarding willingness to participate in HIV vaccine trials. Data on participant retention rates varies widely, and maintaining large cohorts of individuals within Phase III trials presents an important challenge. In addition, the possible impact of trial participation on sexual disinhibition, and response bias on sexual risk-reporting remain as issues for HIV vaccine trials in African contexts.

CONCLUSION

Social and behavioural research forms an important part of preparations for HIV vaccine efficacy trials, and there is a clear need for more research of this type in Sub-Saharan Africa. Innovative approaches are required to address issues such as willingness to participate in vaccine research, participant retention during efficacy trials, and the accurate reporting by participants of sexual risk behaviours.

Multi-level assessment protocol (MAP) for adoption in multi-site clinical trials

The National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) is intended to test promising drug abuse treatment models in multi-site clinical trials, and to support adoption of new interventions into clinical practice. Using qualitative research methods we asked: How might the technology of multi-site clinical trials be modified to better support adoption of tested interventions? A total of 42 participants, representing 8 organizational levels ranging from clinic staff to clinical trial leaders, were interviewed about their role in the clinical trial, its interactions with clinics, and intervention adoption. Among eight clinics participating in the clinical trial, we found adoption of the tested intervention in one clinic only. In analysis of interview data we identified four conceptual themes which are likely to affect adoption and may be informative in future multi-site clinical trials. We offer the conclusion that planning for adoption in the early stages of protocol development will better serve the aim of integrating new interventions into practice.

Brief report: if you build it, they will come: methods for recruiting Latinos into cancer research

BACKGROUND

Latinos have low representation in cancer prevention trials and intervention studies. Culturally appropriate recruitment strategies are needed to address this issue.

OBJECTIVE

To describe and summarize the effectiveness of recruitment strategies used by the Latin American Cancer Research Coalition (LACRC).

DESIGN

Descriptive report of recruitment methods.

PARTICIPANTS

Uninsured Latino immigrants (N=1,170; 77% female, 23% male) from Central and South America recruited to 7 cancer control studies.

APPROACH

The LACRC recruitment model involved inclusion of Latino researchers and providers, and use of culturally acceptable materials released through culturally appropriate outlets such as Latino radio stations.

RESULTS

The overall participation rate was high-96% of patients identified as eligible agreed to participate. Women were excellent referrals for recruiting men to research studies. Additionally, a local Latino radio program was used to efficiently recruit eligible study participants.

CONCLUSIONS

Latinos are interested and willing to participate in cancer control studies when culturally relevant approaches are used. Research teams that partner with Latino researchers and with Latino service providers are important in educating Latinos about cancer control and encouraging participation in research.

The Internet and clinical trials: background, online resources, examples and issues

Both the Internet and clinical trials were significant developments in the latter half of the twentieth century: the Internet revolutionized global communications and the randomized controlled trial provided a means to conduct an unbiased comparison of two or more treatments. Large multicenter trials are often burdened with an extensive development time and considerable expense, as well as significant challenges in obtaining, backing up and analyzing large amounts of data. Alongside the increasing complexities of the modern clinical trial has grown the power of the Internet to improve communications, centralize and secure data as well as to distribute information. As more and more clinical trials are required to coordinate multiple trial processes in real time, centers are turning to the Internet for the tools to manage the components of a clinical trial, either in whole or in part, to produce lower costs and faster results. This paper reviews the historical development of the Internet and the randomized controlled trial, describes the Internet resources available that can be used in a clinical trial, reviews some examples of online trials and describes the advantages and disadvantages of using the Internet to conduct a clinical trial. We also extract the characteristics of the 5 largest clinical trials conducted using the Internet to date, which together enrolled over 26000 patients.

Cytidine 5'-diphosphocholine (CDP-choline) in stroke and other CNS disorders

Brain phosphatidylcholine (PC) levels are regulated by a balance between synthesis and hydrolysis. Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1alpha/beta) activate phospholipase A(2) (PLA(2)) and PC-phospholipase C (PC-PLC) to hydrolyze PC. PC hydrolysis by PLA(2) releases free fatty acids including arachidonic acid, and lyso-PC, an inhibitor of CTP-phosphocholine cytidylyltransferase (CCT). Arachidonic acid metabolism by cyclooxygenases/lipoxygenases is a significant source of reactive oxygen species. CDP-choline might increase the PC levels by attenuating PLA(2) stimulation and loss of CCT activity. TNF-alpha also stimulates proteolysis of CCT. TNF-alpha and IL-1beta are induced in brain ischemia and may disrupt PC homeostasis by increasing its hydrolysis (increase PLA(2) and PC-PLC activities) and inhibiting its synthesis (decrease CCT activity). The beneficial effects of CDP-choline may result by counteracting TNF-alpha and/or IL-1 mediated events, integrating cytokine biology and lipid metabolism. Re-evaluation of CDP-choline phase III stroke clinical trial data is encouraging and future trails are warranted. CDP-choline is non-xenobiotic, safe, well tolerated, and can be considered as one of the agents in multi-drug treatment of stroke.

Comparing efficacy of first-line atypical antipsychotics: no evidence of differential efficacy between risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole

Objective To evaluate the comparative efficacy of the first-line atypical antipsychotics risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole. Methods We reviewed published short-term, randomised, controlled clinical trials of first-line atypical antipsychotics in the treatment of schizophrenia or schizoaffective disorder that used the Positive and Negative Syndrome Scale to assess efficacy. We used a combined overview analysis to compare the extent of improvement in global symptoms and positive and negative symptoms. We did not analyse adverse event data. Results Although we found considerable variation in the degree of improvement with a particular atypical antipsychotic across different studies, the range and average improvement were similar among all first-line atypicals for all efficacy parameters considered. Dosage was a critical determinant of efficacy, although the most effective dose of each agent varied across studies. There were insufficient data for ziprasidone and aripiprazole to allow their inclusion in the formal overview comparison. Conclusion Despite confounding and methodological limitations, the data we reviewed do not support assertions of differential efficacy between the first-line atypical antipsychotics. Additional controlled comparative studies of the atypical antipsychotics should be of particular interest.

Prospective clinical trials of biotherapies in solid tumors: a 5-year survey

PURPOSE

To review the content and quality of prospective clinical trials of biotherapies in solid tumors.

METHODS

Data were collected from the literature between 1990 and 2002 on general study characteristics, patient and disease factors, study methodology, and factors related to completeness of reporting. Quality of phase II studies was evaluated by an ad hoc questionnaire. Descriptive statistics, contingency tables, and the chi-square test were applied.

RESULTS

A total of 334 studies were selected, of which about three quarters were multicenter, with 42.5% reporting phase I, 42.2% phase II or I/II, and 11.9% phase III or II/III studies. Only 13.7% were randomized, and a study design emphasizing statistical analysis was lacking in as many as one third. The assessment of biological endpoints was stated as the primary or secondary goal in half of these studies. Melanoma (17.1%), renal carcinoma (11.1%), gastrointestinal neoplasms (11.1%), and lymphomas (6.3%) were the most studied diseases. Immunotherapies accounted for 182 studies; the remaining 152 reported other biotherapies. Patients with (1) advanced disease (P = 0.003), (2) heavily pretreated neoplasms (P < 0.0001), (3) poor performance status (PS < 2) (P < 0.0001), were more frequently enrolled in studies of biotherapy. Biotherapies were less frequently evaluated in phase III studies (7/152) compared with immunotherapies (33/182) (P < 0.0001). A statistical study design was more frequently identified in biotherapy trials (127/152) compared with immunotherapy trials (98/182) (P < 0.0001). Biological endpoints were less frequently evaluated in phase III studies in both biotherapies (100% no vs 0% yes) and immunotherapies (81.8% no vs 18.2% yes) (P = 0.01, for biotherapies; P < 0.0001, for immunotherapies). Phase I immunotherapy studies more frequently applied biological or molecular criteria for patient selection (41.1%) than phase II (29.3%) and III (3.1%) studies (P < 0.0001).

CONCLUSIONS

The very wide diversity in modalities of conducting and reporting clinical trials of biotherapies of solid tumors and the presence of some methodological pitfalls suggest that the methodological standards for conducting and publishing clinical trials in biotherapies should be improved to enhance the reliability of the body of published data.

Rhinosinusitis: establishing definitions for clinical research and patient care

Background

There is a need for more research on all forms of rhinosinusitis. Progress in this area has been hampered by a lack of consensus definitions and the limited number of published clinical trials.

Objectives

To develop consensus definitions for rhinosinusitis and outline strategies useful in clinical trials.

Methods

Five national societies, The American Academy of Allergy, Asthma and Immunology; The American Academy of Otolaryngic Allergy; The American Academy of Otolaryngology Head and Neck Surgery; The American College of Allergy, Asthma and Immunology; and the American Rhinologic Society formed an expert panel from multiple disciplines. Over two days, the panel developed definitions for rhinosinusitis and outlined strategies for design of clinical trials.

Results

Committee members agreed to adopt the term “rhinosinusitis” and reached consensus on definitions and strategies for clinical research on acute presumed bacterial rhinosinusitis, chronic rhinosinusitis without polyposis, chronic rhinosinusitis with polyposis, and classic allergic fungal rhinosinusitis. Symptom and objective criteria, measures for monitoring research progress, and use of symptom scoring tools, quality-of-life instruments, radiologic studies, and rhinoscopic assessment were outlined for each condition.

Conclusion

The recommendations from this conference should improve accuracy of clinical diagnosis and serve as a starting point for design of rhinosinusitis clinical trials.

Xenotransplantation: infectious risk revisited

Xenotransplantation is a possible solution for the shortage of tissues for human transplantation. Multiple hurdles exist to clinical xenotransplantation, including immunologic barriers, metabolic differences between pigs--the source species most commonly considered--and humans, and ethical concerns. Since clinical trials were first proposed almost 10 years ago, the degree of risk for infection transmitted from the xenograft donor to the recipient has been extensively investigated. A number of potential viral pathogens have been identified including porcine endogenous retrovirus (PERV), porcine cytomegalovirus (PCMV), and porcine lymphotropic herpesvirus (PLHV). Sensitive diagnostic assays have been developed for each virus. Human-tropic PERV are exogenous recombinants between PERV-A and PERV-C sequences and are present in only a subset of swine. Porcine cytomegalovirus can be excluded from herds of source animals by early weaning of piglets. In contrast, the risks associated with PLHV remain undefined. Microbiologic studies and assays for potential xenogeneic pathogens have furthered understanding of risks associated with xenotransplantation. Thus far, clinical xenotransplantation of pig tissues has not resulted in transmission of viral infection to humans; significant risks for disease transmission from swine to humans have not been confirmed. If immunologic hurdles can be overcome, it is reasonable to initiate carefully monitored clinical trials.

What should be the core outcomes in chronic pain clinical trials?

A consensus conference with representatives from academia, governmental agencies, and the pharmaceutical industry met and concluded that clinical trials designed to assess the efficacy and effectiveness of treatments for chronic pain should consider outcomes in six core domains: pain, physical functioning, emotional functioning, patient global ratings of satisfaction, negative health states and adverse events, and patient disposition. In addition, it was acknowledged that there are many secondary domains that might be of importance and should be included in trials depending on the nature of the treatment and population to whom the treatment is targeted.

Topical treatments for seasonal allergic conjunctivitis: systematic review and meta-analysis of efficacy and effectiveness

BACKGROUND

Evidence for the effectiveness of topical treatments, in providing symptomatic relief from ocular allergy, remains uncertain.

AIMS

To assess the effectiveness and relative efficacy of topical treatments for the management of seasonal allergic conjunctivitis.

DESIGN OF STUDY

A systematic review and meta-analysis.

SETTING

A literature search of the Cochrane Library, Medline, and EMBASE bibliographic databases.

METHOD

Double-masked randomised controlled trials were identified, that compared the use of topical mast cell stabilisers (sodium cromoglycate, nedocromil, lodoxamide) with placebo, topical antihistamines with placebo, and topical mast cell stabilisers with topical antihistamines.

RESULTS

A meta-analysis of six trials showed that patients using sodium cromoglycate were 17 times (95% confidence interval [CI] = 4 to 78) more likely to perceive benefit compared with those using a placebo, although this estimate may be partially influenced by publication bias. Five trials indicated that those patients using nedocromil were 1.8 times (95% CI = 1.3 to 2.6) more likely to perceive their allergy to be moderately or totally controlled than those using a placebo. Four trials showed that those using antihistamines were 1.3 times (95% CI = 0.8 to 2.2) more likely to perceive a 'good' treatment effect than those using mast cell stabilisers, although this beneficial effect was not statistically significant. Limited evidence suggests that antihistamines might have a faster therapeutic effect compared to mast cell stabilisers.

CONCLUSION

Overall, these findings confirm the benefit of topical mast cell stabilisers and antihistamines over placebo for the treatment of allergic conjunctivitis. There is, however, insufficient evidence to recommend the use of one type of medication over another. Treatment preferences should therefore be based on convenience of use (with reduced frequency of instillation for some preparations), patient preference, and costs, especially as important side effects were not reported with any medication.

Adjusted chi-square statistics: application to clustered binary data in primary care

The frequency of randomized cluster trials is increasing in primary care research. These trials are differentiated by the randomization method, in which a group of individuals is randomly assigned to an intervention as a cluster rather than as individuals. Characteristically, individuals within a cluster tend to be more alike than individuals selected at random. For instance, evaluating the effect of an intervention across medical care providers at an institutional level or at a physician group practice level fits the randomized cluster model. Three examples in this article show how failure to account for the dependence introduced by unit of randomization can affect the analysis of binary data and the conclusions of randomized cluster trials. Greater consideration of the nested nature of patient, physician, and practice data would increase the quality of primary care research.

Meta-analysis of large randomized controlled trials to evaluate the impact of statins on cardiovascular outcomes

AIMS

Since 2002, there have been five major outcome trials of statins reporting findings from more than 47,000 subjects. As individual trial results differed, we performed a meta-analysis to ascertain the effectiveness and safety of statins overall and in subgroups. The aim of the study was to estimate the effect of statins on major coronary events and strokes, all-cause mortality and noncardiovascular mortality, and in different subgroups.

METHODS

PubMed was searched for trials published in English. Randomized placebo-controlled statin trials with an average follow up of at least 3 years and at least 100 major coronary events were included. For each trial, the statin used, number and type of subjects, proportion of women, mean age and follow up, baseline and change in lipid profile, cardiovascular and non-cardiovascular outcomes were recorded.

RESULTS

Ten trials involving 79,494 subjects were included in the meta-analysis. Due to heterogeneity, ALLHAT-LLT was excluded from some analyses. Statin therapy reduced major coronary events by 27% (95%CI 23, 30%), stroke by 18% (95%CI 10, 25%) and all-cause mortality by 15% (95%CI 8, 21%). There was a 4% (95%CI -10, 3%) nonsignificant reduction in noncardiovascular mortality. The reduction in major coronary events is independent of gender and presence of hypertension or diabetes. The risk reduction was greater in smokers (P < 0.05). Coronary events were reduced by 23% (95%CI 18, 29%) in pravastatin trials and 29% (95%CI 25, 33%) in five trials using other statins. Pravastatin reduced strokes by 12% (95%CI 1, 21%) whilst other statins reduced strokes by 24% (95%CI 16, 32%) (P = 0.04).

CONCLUSIONS

Statins reduce coronary events, strokes and all-cause mortality without increasing noncoronary mortality. The benefits accrue in men and women, hypertensives and normotensives, diabetics and nondiabetics, and particularly in smokers. Pravastatin appears to have less impact on strokes.