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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).

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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.

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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.

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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.

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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)

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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.

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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.

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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.

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