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This presentation describes some of the issues that arise when applying the clinical-trial approach of conventional medicine to complementary and alternative medicine (CAM) modalities. Conventional medicine has been making the evolution to using an evidence base and to making recommendations only when the evidence is strong. The National Center for Complementary Medicine (NCCAM), one of twenty-five Institutes or Centers of the National Institutes of Health (NIH), is working to hold CAM to the same high standards, not by rejecting previous CAM research, but by building on that strong evidence base of what works and what is safe. The process for conventional drug and device development follows an orderly process of preclinical studies (usually on animals), phase I, phase II, and phase III studies (with the large human clinical trial phase taking place in phase III). Today, the randomized controlled trial is recognized as providing the highest level of scientific evidence. This conventional medicine approach to development is now being used to develop complementary and alternative therapies. For instance, the discovery and development of Taxol (Bristol-Meyers Squibb, New York, NY), an extract from the bark of the Pacific yew tree that is now a widely used chemotherapeutic agent, followed the conventional pathway to approval and marketing. But for most CAM products, the pathway is not so straightforward. Most CAM therapies are traditional therapies or new products that are already available to the public. Most of what is known about these therapies is of an anecdotal nature. There has been little isolation of the active principals from the crude product and there has usually been no preclinical testing. This presentation details various approaches and programs that address how to plan and conduct a rigorous clinical trial of a CAM product. And, while it takes a good deal of persistence and a strong focus on what are the critical principals in a trial, I conclude that it is possible to apply randomized controlled trials to most of the CAM modalities. [ABSTRACT FROM AUTHOR]

In 1998, the National Institutes of Health (NIH) formed the National Center for Complementary and Alternative Medicine (NCCAM) from what had formerly been the Office of Alternative Medicine. This presentation opens with a brief discussion on the history of the NIH and the development of CAM at the NIH before moving on to the work of the NCCAM. The NCCAM is moving toward an integration of CAM therapies into conventional medicine, when there is evidence for the value of CAM. One of twenty-five institutes or centers at the NIH, the NCCAM looks at evidence-based medicine and public health. In this context, 'public health' means educating the public about its health. The NCCAM supports training to conduct research and plays an important role in disseminating information to the public and to health providers about what works and what is safe. This evolves into the concept of evidence-based medical and public-health practices, that is, making decisions on the basis of evidence from scientifically rigorous studies that are sufficiently large to provide a confident estimate of biologically and medically important benefits and risks. In the hierarchy of generating scientific evidence, randomized controlled trials are considered the 'gold standard.' The NCCAM entertains proposals for studies that come spontaneously from investigators, or, upon identifying an existing need that is not being met by the investigative community, the NCCAM can initiate a request for proposals. Every proposal is subjected to a rigorous application and review process. Another possible step in the assessment of the evidence from clinical trials is to do a systematic analysis of several studies to bring together all the information that is available. Systematic reviews of smaller studies that individually might have an insufficient sample size can assist in making treatment decisions, but, importantly, they can lead the NCCAM in the development of future, definitive studies. Training to conduct research is especially important to CAM. This presentation outlines several approaches the NCCAM has to training (see http://nccam.nih.gov). [ABSTRACT FROM AUTHOR]

Surrogate biomarkers for clinical outcomes afford scientific and economic efficiencies when investigating nutritional interventions in chronic diseases. However, valid scientific results are dependent on the qualification of these disease markers that are intended to be substitutes for a clinical outcome and to accurately predict benefit or harm. In this article, we examine the challenges of evaluating surrogate markers and describe the framework proposed in a 2010 Institute of Medicine report. The components of this framework are presented in the context of nutritional interventions for chronic diseases. We present case studies of 2 well-accepted surrogate markers [blood pressure within sodium intake and cardiovascular disease (CVD) context and low density lipoprotein-cholesterol concentrations within a saturated fat and CVD context]. We also describe additional cases in which the evidence is insufficient to validate their surrogate status. Guidance is offered for future research that evaluates or uses surrogate markers., (© 2017 American Society for Nutrition.)

Dietary Reference Intakes (DRIs) are used in Canada and the United States in planning and assessing diets of apparently healthy individuals and population groups. The approaches used to establish DRIs on the basis of classical nutrient deficiencies and/or toxicities have worked well. However, it has proved to be more challenging to base DRI values on chronic disease endpoints; deviations from the traditional framework were often required, and in some cases, DRI values were not established for intakes that affected chronic disease outcomes despite evidence that supported a relation. The increasing proportions of elderly citizens, the growing prevalence of chronic diseases, and the persistently high prevalence of overweight and obesity, which predispose to chronic disease, highlight the importance of understanding the impact of nutrition on chronic disease prevention and control. A multidisciplinary working group sponsored by the Canadian and US government DRI steering committees met from November 2014 to April 2016 to identify options for addressing key scientific challenges encountered in the use of chronic disease endpoints to establish reference values. The working group focused on 3 key questions: 1) What are the important evidentiary challenges for selecting and using chronic disease endpoints in future DRI reviews, 2) what intake-response models can future DRI committees consider when using chronic disease endpoints, and 3) what are the arguments for and against continuing to include chronic disease endpoints in future DRI reviews? This report outlines the range of options identified by the working group for answering these key questions, as well as the strengths and weaknesses of each option., (© 2017 American Society for Nutrition.)

The incidence and prevalence of inflammatory bowel disease are rising. Crohn's disease and ulcerative colitis each have distinct features. Treatments are changing rapidly, and there are many new drugs in the pipeline. Health maintenance also plays a key role in the care of this patient population., (©2016 by the North Carolina Institute of Medicine and The Duke Endowment. All rights reserved.)

The PhenX (consensus measures for Phenotypes and eXposures) Toolkit (https://www.phenxtoolkit.org/) offers high-quality, well-established measures of phenotypes and exposures for use by the scientific community. The goal is to promote the use of standard measures, enhance data interoperability, and help investigators identify opportunities for collaborative and translational research. The Toolkit contains 395 measures drawn from 22 research domains (fields of research), along with additional collections of measures for Substance Abuse and Addiction (SAA) research, Mental Health Research (MHR), and Tobacco Regulatory Research (TRR). Additional measures for TRR that are expected to be released in 2015 include Obesity, Eating Disorders, and Sickle Cell Disease. Measures are selected by working groups of domain experts using a consensus process that includes input from the scientific community. The Toolkit provides a description of each PhenX measure, the rationale for including it in the Toolkit, protocol(s) for collecting the measure, and supporting documentation. Users can browse measures in the Toolkit or can search the Toolkit using the Smart Query Tool or a full text search. PhenX Toolkit users select measures of interest to add to their Toolkit. Registered Toolkit users can save their Toolkit and return to it later to revise or complete. They then have options to download a customized Data Collection Worksheet that specifies the data to be collected, and a Data Dictionary that describes each variable included in the Data Collection Worksheet. The Toolkit also has a Register Your Study feature that facilitates cross-study collaboration by allowing users to find other investigators using the same PhenX measures., (Copyright © 2015 John Wiley & Sons, Inc.)

Purpose: Pregnancy and childbirth are normal conditions, but complications and adverse outcomes are common. Both genetic and environmental factors influence the course of pregnancy. Genetic epidemiologic research into pregnancy outcomes could be strengthened by the use of common measures, which would allow data from different studies to be combined or compared. Here, we introduce perinatal researchers to the PhenX Toolkit and the Collections related to pregnancy and childbirth., Methods: The Pregnancy and Birth Collections were drawn from measures in the PhenX Tooklit. The lead author selected a list of measures for each Collection, which was reviewed by the remaining authors and revised on the basis of their comments. We chose the measures we thought were most relevant for perinatal research and had been linked most strongly to perinatal outcomes., Results: The Pregnancy and Birth Health Conditions Collection includes 24 measures related to pregnancy and fertility history, maternal complications, and infant complications. The Pregnancy and Birth Outcome Risk Factors Collection includes 43 measures of chemical, medical, psychosocial, and personal factors associated with pregnancy outcomes., Conclusions: The biological complexity of pregnancy and its sensitivity to environmental and genomic influences suggest that multidisciplinary approaches are needed to generate new insights or practical interventions. To fully exploit new research methods and resources, we encourage the biomedical research community to adopt standard measures to facilitate pooled or meta-analyses., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The PhenX (consensus measures for Phenotypes and eXposures) Toolkit (https://www.phenxtoolkit.org/) offers high-quality, well-established measures of phenotypes and exposures for use by the scientific community. The Toolkit contains 295 measures drawn from 21 research domains (fields of research). The measures were selected by Working Groups of domain experts using a consensus process that included input from the scientific community. The Toolkit provides a description of each PhenX measure, the rationale for including it in the Toolkit, protocol(s) for collecting the measure, and supporting documentation. Users can browse by measures, domains, or collections, or can search the Toolkit using the Smart Query Tool. Once users have selected some measures, they can download a customized Data Collection Worksheet that specifies what information needs to be collected, and a Data Dictionary that describes each variable included in their Data Collection Worksheet. To help researchers find studies with comparable data, PhenX measures and variables are being mapped to studies in the database of Genotypes and Phenotypes (dbGaP)., (© 2011 by John Wiley & Sons, Inc.)

The potential for genome-wide association studies to relate phenotypes to specific genetic variation is greatly increased when data can be combined or compared across multiple studies. To facilitate replication and validation across studies, RTI International (Research Triangle Park, North Carolina) and the National Human Genome Research Institute (Bethesda, Maryland) are collaborating on the consensus measures for Phenotypes and eXposures (PhenX) project. The goal of PhenX is to identify 15 high-priority, well-established, and broadly applicable measures for each of 21 research domains. PhenX measures are selected by working groups of domain experts using a consensus process that includes input from the scientific community. The selected measures are then made freely available to the scientific community via the PhenX Toolkit. Thus, the PhenX Toolkit provides the research community with a core set of high-quality, well-established, low-burden measures intended for use in large-scale genomic studies. PhenX measures will have the most impact when included at the experimental design stage. The PhenX Toolkit also includes links to standards and resources in an effort to facilitate data harmonization to legacy data. Broad acceptance and use of PhenX measures will promote cross-study comparisons to increase statistical power for identifying and replicating variants associated with complex diseases and with gene-gene and gene-environment interactions.

Purpose of Review: To highlight standard PhenX (consensus measures for Phenotypes and eXposures) measures for nutrition, dietary supplements, and cardiovascular disease research and to demonstrate how these and other PhenX measures can be used to further interdisciplinary genetics research., Recent Findings: PhenX addresses the need for standard measures in large-scale genomic research studies by providing investigators with high-priority, well established, low-burden measurement protocols in a web-based toolkit (https://www.phenxtoolkit.org). Cardiovascular and Nutrition and Dietary Supplements are just 2 of 21 research domains and accompanying measures included in the PhenX Toolkit., Summary: Genome-wide association studies (GWAS) provide promise for the identification of genomic markers associated with different disease phenotypes, but require replication to validate results. Cross-study comparisons typically increase statistical power and are required to understand the roles of comorbid conditions and environmental factors in the progression of disease. However, the lack of comparable phenotypic, environmental, and risk factor data forces investigators to infer and to compare metadata rather than directly combining data from different studies. PhenX measures provide a common currency for collecting data, thereby greatly facilitating cross-study analysis and increasing statistical power for identification of associations between genotypes, phenotypes, and exposures.

Public concerns about the perils associated with incomplete or delayed reporting of results from clinical trials has heightened interest in trial registries and results databases. Here we review the current status of trial registration efforts and the challenges in developing a comprehensive system of trial registration and reporting of results. ClinicalTrials.gov, the largest trial registry with 36 249 trials from approximately 140 countries, has procedures in place to help ensure that records are valid and informative. Key challenges include the need to minimize inadvertent duplicate registrations, to ensure that interventions have unambiguous names, and to have a search engine that identifies all trials that meet a user's specifications. Recent policy initiatives have called for the development of a database of trial results. Several issues confound the implementation of such a database, including the lack of an accepted format or process for providing summaries of trial results to the public and concerns about disseminating data in the absence of independent scientific review.

The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial is a multi-site effectiveness study funded by the National Institute of Mental Health (NIMH) with the aim of identifying successful, acceptable and cost-effective treatment strategies for outpatients with unremitted depression. With enrollment of 4,041 adults with major depressive disorder (MDD), it is the largest controlled psychiatric treatment study ever undertaken. In the course of developing procedures to ensure that ambitious enrollment goals were met, a number of ethical and practical issues became apparent that underscore the conflicts between effectiveness research and human subject protections. These are delineated as they relate to study design; eligibility criteria; incentives to subjects; investigators and clinical sites; the complementary roles of clinical research coordinators (CRCs) and study clinicians; and recruitment and consent procedures. The STAR*D trial exemplifies the interplay and tension between those strategies that integrate research and clinical aims and roles in the service of enhancing external validity, site participation, and recruitment and retention versus those strategies that differentiate research and clinical treatment in the service of research integrity and human subject protections. We hope that a discussion of these key challenges and dilemmas and how they have been addressed will help inform future discussions concerning design and conduct of ethical effectiveness trials designed to optimize care in real world clinical settings.

Background: The metabolic syndrome, associated with increased risk of type 2 diabetes mellitus and cardiovascular disease, begins to develop during adolescence., Objective: We sought to identify early predictors of the presence of the syndrome at the ages of 18 and 19 years in black and white girls., Methods: Using longitudinal data on participants from 2 centers in the National Heart, Lung, and Blood Institute Growth and Health Study, a 10-year cohort study, we applied cutoffs from the Adult Treatment Panel III to document changes in the prevalence of abnormal syndrome elements and the syndrome in girls aged 9 and 10 years, when cases were rare, and those aged 18 and 19 years, when prevalence had reached 3%. Longitudinal regression models identified early predictors for the presence of the syndrome., Results: Only 1 girl of each race had > or =3 factors at ages 9 and 10 (0.2%), but 20 black girls (3.5%) and 12 white girls (2.3%) had the syndrome 10 years later. Low high-density lipoprotein cholesterol was prevalent throughout the period in both black and white girls. The prevalence of other variables was low at enrollment but increased during follow-up, except for abnormal triglyceride levels in black girls, which remained low throughout follow-up. In multivariate models, early measures of waist circumference and triglyceride level were significant predictors for development of the syndrome., Conclusion: The strong association of central adiposity with the development of the metabolic syndrome suggests that early interventions aimed at managing preteen obesity could reduce risk of developing the syndrome.

Objective: Age at onset of type 2 diabetes has decreased during the past 20 years, especially in black women. Studies of factors associated with insulin resistance and hyperglycemia in preadolescent and adolescent populations are essential to understanding diabetes development., Research Design and Methods: The National Heart, Lung, and Blood Institute (NHLBI) Growth and Health Study (NGHS) is a 10-year cohort study of the development of obesity in black and white girls. Two NGHS centers examined the associations of obesity, puberty, and race with fasting insulin, glucose, and homeostasis model assessment of insulin resistance (HOMA-IR; a calculated index of insulin resistance) measures at 9-10 years of age (baseline) and 10 years later., Results: Black girls had greater baseline and year-10 BMI than white girls, with a greater 10-year incidence of obesity. BMI-insulin correlations were positive in both black and white girls at both visits, but insulin remained higher in black girls after controlling for BMI. In black girls, insulin and HOMA-IR were higher in the prepubertal period (before the emergence of racial differences in BMI), increased more during puberty, and decreased less with its completion. Baseline BMI predicted year-10 glucose and the development of impaired fasting glucose (IFG) in black girls. In white girls, the rate of BMI increase during follow-up predicted these outcomes. The 10-year incidence of diabetes in black girls was 1.4%., Conclusions: Black-white differences in insulin resistance are not just a consequence of obesity, but precede the pubertal divergence in BMI. The development of IFG appears to be a function of the rate of increase of BMI in white girls and early obesity in black girls.

Objective: Investigators have assessed the utility of antispasmodic agents in colonoscopy, with conflicting results. The aim of this study is to determine the effects of premedication with hyoscyamine, an anticholinergic antispasmodic, on outcomes in colonoscopy., Methods: A total of 165 patients undergoing elective colonoscopy were randomized in a double blinded fashion to one of three arms: intravenous hyoscyamine (0.25 mg), oral hyoscyamine (0.25 mg), or placebo, administered 20-40 min before colonoscopy. Primary outcome measures included insertion time to cecum, patient's assessment of pain, and physician assessment of spasm. Secondary outcome measures included amount of analgesic medications used, total procedure time, amount and type of pathology visualized, and physician assessment of patient's pain., Results: Bivariate analysis showed no difference between the three groups in insertion time (13.8 min, 14.8 min, and 13.8 min for placebo, intravenous hyoscyamine, and oral hyocyamine, respectively), analgesic medication necessary, or any other primary or secondary outcome variable. Multivariate analysis controlling for potential confounders also failed to demonstrate any differences between the groups. Women had higher procedure duration and analgesic requirement, and reported more pain than did men., Conclusions: This randomized, double blinded, placebo-controlled trial did not demonstrate efficacy of either intravenous or oral hyoscyamine as a premedication for colonoscopy.

Prevention of disease and disability and preservation of health are compelling strategies that are endorsed by the public, health care providers, and researchers. Despite this general acceptance of the concept, the "devil is in the details." What can and should be recommended with confidence to the public and health care providers regarding prevention and how can these recommendations be implemented? Prevention programs should be based on durable evidence of efficacy and should assure that the benefits of interventions and changes exceed the risks. The latter is particularly important for population-based primary prevention because many are influenced but fewer may benefit. Prevention research must provide the evidence of benefit and risk. The responsibility of the National Institutes of Health (NIH) is to develop the scientific basis for prevention and to train prevention scientists who are responsible for creating this science base. The interpretation and dissemination of information from research studies are important and necessary aspects to assure translation of the science into personal and public health practices. The components of prevention research are investigation of the factors that place individuals and groups at risk of disease and disability; trials of the interventions that can modify this risk; and testing the approaches that can effectively implement beneficial changes. NIH is committed to addressing these endeavors, and its individual Institutes and Centers support a broad portfolio of prevention research. This paper will provide an overview of NIH support, the functional relationships of prevention research within NIH, and background information that can be useful to those interested in research.

Enrollment in cardiac rehabilitation has been reported to improve exercise capacity, psychological well-being, and survival. However, participation rates are low and the reasons for nonparticipation have not been adequately defined. The purpose of this study was to evaluate the major correlates of nonparticipation and to examine the level of participation of patients who stand to benefit most on the basis of preenrollment functional status and health behaviors. Three hundred ninety-three patients undergoing coronary artery bypass surgery (1) had baseline functional status and quality-of-life data collected, and (2) were recruited for participation in the Duke Center for Living comprehensive 3-week post-coronary bypass surgery rehabilitation program. Baseline demographic, clinical, catheterization, functional status, psychological status, and health behavior descriptors were analyzed to identify univariate and multivariable correlates of a patient's decision to participate in the program. At baseline, most clinical factors were similar in participants (n = 52) and nonparticipants (n = 341), but the nonparticipants were more often women (26% vs 12%, p = 0.02). Participants were also more likely to be employed (63% vs 45%, p = 0.02) and had a higher education and income distribution than nonparticipants (both p = 0.001). On 2 separate scales, nonparticipants had significantly more baseline functional impairment than participants (both p = 0.001). In multivariable analysis, the independent correlates of higher participation rates were: higher education (college graduates 71% more likely to participate than high school graduates) and better baseline Duke Activity Status Index (patients with mild functional impairment were at least 42% more likely to participate than patients with moderate impairment).(ABSTRACT TRUNCATED AT 250 WORDS)

The Women's Health Initiative (WHI) addresses some of the major health concerns of postmenopausal women. It is designed to test whether long-term preventive measures will decrease the incidence of cardiovascular disease, certain cancers, and fractures, and it seeks to find better predictors of future health and disease in older women. This report traces the evolution of the clinical trial and observational study (CT/OS) components of WHI from early planning in the 1980s to the current status of the WHI CT/OS as an integrated, ongoing clinical study. Particular attention is directed to the antecedent planning meetings and feasibility studies that formed the underpinnings of the WHI. The issues of hormone replacement therapy and of the optimal diet for postmenopausal women were investigated for almost a decade prior to WHI. However, no studies of sufficient size and duration to confidently test the value and risks of these approaches were initiated because of the cost and insufficient political commitment. The initiation of WHI in 1991 represents the confluence of scientific need and capability with the social priorities to improve the health and welfare of women.

Secular trends in blood pressure among young adults reflect the proportion of the population at risk of developing hypertension and may be markers of progress in primary prevention. National health examination data from three successive surveys were analyzed to assess blood pressure trends for adult blacks and whites aged 18-34 years in two body mass index (BMI; weight (kg)/height (m)2) strata (< 25 or > or = 25). Blood pressure was categorized into a four-point ordinal scale using the weighted, within-sex 50th, 75th, and 90th percentiles for 18- to 24-year-old adults in the 1960-1962 survey. The effects were analyzed with cumulative logit models with alpha = 0.01. The systolic blood pressure decreased moderately for 25- to 34-year-old males and for females except those aged 25-34 years with a BMI of > or = 25. Diastolic blood pressure increased among males with a BMI of > or = 25 and among white males with a BMI of < 25, but did not show a significant overall trend among females. A BMI of > or = 25 was associated with substantially higher blood pressure in each survey, except for one age-sex-race subgroup. Racial differences within BMI were less consistent than the differences across BMI strata. In summary, the situation with respect to hypertension among females may have improved during this time period but for males may have worsened with respect to diastolic blood pressure. Data for both sexes support a need for population-wide obesity prevention to reduce the incidence of hypertension.

Idiopathic dilated cardiomyopathy (IDC) is the primary indication for cardiac transplantation, with associated costs of approximately $177 million per year. Recognizing the economic implications of IDC, the increasing incidence, and the limited information on pathogenesis and prognosis, the National Heart, Lung, and Blood Institute convened a workshop on the Prevalence and Etiology of Idiopathic Dilated Cardiomyopathy on June 13 to 14, 1991. The difficulties of studying the disease were reviewed, including its relatively low prevalence, its potentially pluricausal nature, and the fact that it is often a diagnosis of exclusion. Still, it presents significant challenges to the cardiovascular scientific community, since the mechanism of myocardial damage and related etiologic and prognostic factors are virtually unknown. The development of more reliable measures of immune-mediated damage and noninvasive measures of impaired cardiac function present new research opportunities in this disorder. Standardized diagnostic criteria for use in observational and interventional trials were developed, and priorities for future research were proposed. Population-based registries and nested case-control studies, where feasible, are appropriate study designs for tracking incidence and prevalence, and for identifying risk factors, respectively. Interventional studies should focus on secondary prevention, through modifying immune-mediated damage in clinically evident dilated cardiomyopathy, and through prevention of sudden death in patients with the disorder. Primary prevention trials must await the identification of modifiable risk factors and of appropriate and effective interventions.

The Duke Data Bank for Cardiovascular Diseases is an observational data bank capturing baseline, treatment, and follow-up information on patients referred for evaluation of suspected coronary artery disease. From 6829 patients referred between 1969 and 1990 for diagnostic angiography, baseline cholesterol levels were determined as part of the standard clinical procedure. Baseline total cholesterol values were found to be related to the presence of coronary disease in men and women, although in the elderly little evidence for a significant relationship was found. Formal tests for interactions revealed a significant interaction between age and cholesterol but not between gender and cholesterol. In subgroup analyses using the Cox proportional hazards model, no relationship was found between cholesterol and either cardiovascular death or total cardiac events (death or nonfatal myocardial infarction) in 2038 medically treated patients with 5 to 20 years of follow-up. In the subgroup of 1798 surgically treated patients, there was also no relationship between baseline cholesterol level and these end points. Finally, detailed lipid analysis was done at baseline and 6-month angiography in a second population of 759 patients undergoing percutaneous coronary angioplasty between 1986 and 1989. No substantial relationship between baseline or follow-up cholesterol, low-density or high-density lipoproteins, or triglyceride levels and restenosis was found.

The value of serum total cholesterol measurement in predicting coronary heart disease (CHD) is well established in middle-aged men, but has been questioned in middle-aged women and older people of both sexes. To address this, the most recent follow-up data from 25 populations in 22 US and international cohort studies were presented and analyzed at a recent National Heart, Lung, and Blood Institute (NHLBI) workshop. Crude relative and absolute excess risks of fatal CHD were determined for individual studies and pooled across studies to determine pooled risk estimates. Serum total cholesterol and low-density-lipoprotein (LDL) cholesterol levels predicted fatal CHD in middle-aged (< 65 years) and older (> or = 65 years) men and women, though the strength and consistency of these relationships in older women were diminished. High-density-lipoprotein (HDL) cholesterol levels inversely predicted CHD in middle-aged men and women and in older women, but not in older men. Data for minority groups and for overseas populations were similar to those for white people in the United States. Relative risk estimates were generally lower for older than for middle-aged subjects, but absolute excess risk was greater. Older people and middle-aged women with elevated cholesterol levels are clearly at increased risk of coronary disease; whether this risk can be modified by dietary or drug therapy, and at what level intervention is appropriate, must not be determined.

Despite substantial basic and clinical efforts to address the problem of restenosis after percutaneous coronary intervention, effective preventive therapies have not yet been developed. Nevertheless, the accumulated information has provided much insight into the process of restenosis in addition to allowing standards to be developed for adequate clinical trials. The pathophysiology of restenosis increasingly appears to be distinct from that of primary atherosclerosis. Restenosis involves elastic recoil, incorporation of thrombus into the lesion and fibrocellular proliferation in varying degrees in different patients. Lack of an animal model that satisfactorily mimics restenosis is a major impediment to further understanding of the process. Clinical studies are hampered by difficulties in finding a single unifying definition of restenosis and by variable methods of reporting follow-up. Reporting of clinical outcomes of all patients in angiographic substudies would allow a more satisfactory interpretation of the results of clinical trials. Current noninvasive test results are not accurate enough to substitute for angiographic and clinical outcome data in intervention trials. In the majority of observational studies, only diabetes and unstable angina have emerged as consistently associated with restenosis; whereas most of the standard risk factors for atherosclerosis have a less consistent relation. Disappointingly, the new atherectomy and laser technologies have not affected restenosis rates. The one possible exception is coronary stenting, as a result of the larger luminal diameter achieved by the placement of the stent. In conclusion, although substantial continued effort is necessary to explore the basic aspects of cellular proliferation and mechanical alteration of atherosclerotic vessels, attention to the principles of clinical trials and observation are required to detect the impact of risk factors and interventions on the multifactorial problem of restenosis. Adequate sample sizes, collection of clinical and angiographic outcomes and factorial study designs hold promise for unraveling this important limitation of percutaneous intervention.

This review summarizes current knowledge about differences in cardiovascular disease and its risk factors among minorities in the US population. The limited information available about differences in the association of obesity with cardiovascular disease risk factors in minorities is described. Our thesis is that environment and its evolutionary influence are important in risk-factor changes, although genetic characteristics moderate the impact of these factors. This review attempts to illustrate how studies of minority groups can help us to understand the importance and interaction of factors leading to increased cardiovascular disease risk. We suggest guidelines for the design of studies that will help us to better explain differences in cardiovascular disease and its risk factors among minorities and to improve therapy for this common disorder. Because diabetes is a major topic of the First International Conference on Race, Ethnicity, and Health, data on this disease are used in many of the examples presented.

Data from the 1980 National Medical Care Utilization and Expenditure Survey were analyzed to place the costs for injuries in the context of all medical costs and to describe the distribution by demographic and diagnostic groups. For the non-institutionalized population, injuries, which include intentional and unintentional, were the second leading cause of direct medical costs, accounting for $16,745 million in medical care expenditures and a major contributor to work loss and disability in the US. For the working-age population (17-64 years) injuries were the leading cost category ($11,341 million) and the third most costly category for persons 65 years of age and over ($3,479 million). The preponderance of costs were attributable to hospital-based care. Direct medical costs were disproportionately greater for males, White and other persons, and for those with household incomes less than $5,000. Injury morbidity also accounts for major indirect costs. Fractures accounted for the highest direct medical costs, greatest per capita charges (based on those with charges), and largest number of restricted activity days. These national estimates document the economic importance of injuries and direct public attention to policy imperatives related to research and prevention.

The advent of physician assistants raises questions regarding their appropriate utilization and monitoring. To determine practice patterns of physician assistants in settings independent of training programs, we studied 14 primary care practices in the rural southeast. Detailed observations, including appropriateness of medical care, were made on 788 outpatient-provider encounters. Physician assistants handled minor medical problems well and 61% of the patients observed in these practices fitted this category. Three practice patterns were observed: all patients were seen by the assistant initially, followed by the physician; patients managed concurrently by physician and assistant were not preselected; and patients with specific problems were assigned to the assistant. Properly managed, each of these patterns yielded competent care. Using these observations, proposed models of management and audit are presented for each practice pattern.

We assessed the effect of "healed" childhood renal disease on subsequent pregnancies by following-up a cohort of 224 children initially hospitalized with kidney disease. The pregnancy experience in this cohort was compared to two "control" cohorts comprising 81 female siblings and 191 age-matched female patients hospitalized contemporaneously for respiratory infection. The incidence of spontaneous abortion, stillbirth, and pregnancy-associated hypertension was not different among the cohorts; however, the incidence of infants with low birth weights was significantly greater in the renal and respiratory disease groups. Childhood kidney disease followed by impaired renal function (serum creatinine greater than 1.5 mg/dL) was associated with greater maternal and fetal morbidity. Kidney disease in childhood followed by apparent healing and no functional renal impairment does not have an adverse effect on maternal welfare, although the incidence of infants with low birth weight is apparently increased.

To test the hypothesis that subtle changes in the resting electrocardiogram can have predictive value for subsequent cardiovascular disease, the authors evaluated serial electrocardiograms from a cohort of initially healthy men and related these to later development of ischemic heart disease. The cohort of 1056 men originally physically qualified for naval aviation were followed from 24-61 years of age between 1940 and 1977. Resting electrocardiograms were obtained at 24, 36, 42, and 54 years of age. Particular emphasis was directed to measurement of electrocardiographic intervals, amplitudes, and vectorial orientation. The potential effects of weight, blood pressure, and other major risk factors on electrocardiographic changes were controlled in analysis. At younger ages, the amplitude of the T wave in lead 2 and the change in P-R interval were predictive of cardiovascular disease. With aging of the cohort, more leftward orientation of the frontal plane QRS and T forces were predictive, as were the serial changes in the angle between QRS and T. When major risk factors (smoking, blood pressures, and serum cholesterol) were included in a predictive model, addition of electrocardiographic changes significantly improved prediction of ischemic heart disease. These subtle serial changes may be helpful to epidemiologists and clinical investigators in assessing risk of subsequent cardiovascular disease.