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National Children’s Health Study - Dr. Peter Scheidt
Dr. Scheidt thanked NVAC for the opportunity to share information about the National Children’s Study (NCS). He noted that he would be speaking for Dr. Duane Alexander, the Director of the National Institute of Child Health and Human Development (NICHD). Dr. Scheidt serves as the Director of the Program Office of NCS at NICHD. He noted that he would also be speaking on behalf of the interagency coordinating committee comprised of the staff senior scientists from agencies supporting the planning and implementation of NCS – HHS, NICHD, CDC, the National Institute of Environmental Health Sciences (NIEHS), and EPA.
A longitudinal study of children’s health has been discussed for decades since the NINDS Collaborative Perinatal Project. The specific proposal for NCS began with the President’s Task Force on Environmental Health and Safety Risks, which is chaired by the Secretary of HHS and the Administrator of EPA with seven other Cabinet officers. It was charged with developing national strategies to reduce and control the risks of environmental influences on children’s health and development. As the task force, staffed by senior scientists in those agencies, grappled with their charge, they realized that the information they needed to inform those recommendations were not available. There are a number of models and examples in which children are much more vulnerable from environmental risks than adults, such as with lead and alcohol (fetal alcohol syndrome). There are known exposures of high frequency even at low levels, such as pesticides. There are also a number of conditions for which there is evidence, but no conclusive evidence, of the contribution of environmental exposures to conditions such as infantile autism, diabetes, asthma, birth defects, and premature birth. The convergence of these factors led the task force to be concerned about how to meet the charge and to realize that existing research was too limited in size and scope to provide guidance. They concluded that a study that could link exposures to outcomes was essential and had to be large enough to address concerns about relatively low prevalence conditions, although burdensome and important. In October 2000, Congress passed the Children’s Health Act of 2000, which authorized NICHD with a consortium of federal agencies interested and concerned about the health and development of children and environmental exposures to undertake the planning.
NCS is a longitudinal study of children, their families, and their environment. The study will be national in scope; be hypothesis driven; define “environment” very broadly (chemical, physical, behavioral, social, cultural, and biological); and study uncommon, but important and burdensome conditions (autism, diabetes, cerebral palsy, and others) requiring a sample size of about 100,000. The exposure period begins in early pregnancy and continues throughout childhood and into adulthood. It is essential to understand how environment influences genetic expression and to look at the ways environmental factors interact with genotype and genetic information. The study would be conducted using state-of-the-art technology to allow the most efficient and economical measures, to allow tracking with satellite technology and global positioning, and to enable the study to handle massive data sets. The study is a Federal consortium with over 40 entities, including all of the NIH institutes, CDC centers, and other Cabinet level agencies (e.g., Department of Education, HUD, Department of Agriculture). The study will be carried out with extensive public-private partnerships. It not only carries out a core federally-funded project, but would incorporate ancillary studies focusing in greater depth on sub-populations with additional in-depth studies funded through public-private partnerships. Finally, understanding that the study is hypothesis-driven and given the framework and boundaries for the study, a study of this size and complexity would serve as an extraordinarily valuable resource and should be planned and carried out in such a way to optimize that potential for future hypothesis testing.
As a guiding principle, the sample should be as generalizable as possible to the U.S. population and able to address the special concerns of special populations – such as the economically underserved populations, minority populations, rural or agricultural populations, and industrially exposed populations. He noted the importance of looking at early pregnancy risk factors and including women of child-bearing age in the sample.
There has been considerable consultation with the NCS Advisory Committee and a special panel of experts and a series of detailed analyses and scientific reviews looked at how multiple factors affect sampling strategies. After a great deal of work, they decided to use a national probability sample, not to obtain prevalence estimates (which can be obtained by more efficient methods), but to assure that the exposure-outcome relationships are applicable to the U.S. population and that they do not miss important exposures. To be able to describe and understand what goes on in children’ environments, one must know what happens in their communities and where they live. Multiple data points are necessary to be able to do this. For this reason and the feasibility and economics of carrying out the study, the sample will be fairly densely clustered. In this multi-state sampling strategy, the first stage will be picked on a probability basis to ensure the best possible representation. The feasibility of carrying out this sampling strategy will need to be tested with extensive pilot studies. Although probability sampled, the study will be implemented through multiple centers around the country in a range of 40 centers.
The priority environmental exposures of special interest in the study are physical exposures, such as characteristic of housing, neighborhoods and communities, climate, and radiation; chemical exposures, such as air, water, soil, food, dust, industrial products, and pharmaceuticals; biological environment, including intrauterine factor, infection, nutrition, and inflammatory and metabolic response; genetic data; and psychosocial milieu, such as influence of family, socioeconomics, community attributes, and stress.
Priority outcomes include pregnancy and intrauterine growth, infection, nutrition, preterm birth, birth defects, and fetal influences on adult health; neurodevelopment and behavior, such as cognitive development (IQ), autism, learning disabilities, schizophrenia, depression, adjustment, normal variation, and resilience; injury, which is the leading cause of morbidity and mortality in children after 1 year of age; asthma, because of its importance as a major morbidity of children; and obesity and physical development.
Hypotheses are necessary for framing the study. He noted that no single hypothesis would drive a study of this size and complexity, and that this should be thought of more as a program of research where multiple hypotheses provide the guidance and structure for the study. It is necessary to work through hypotheses to assure the study is capable of answering the “big issue” questions that it is charged with. Dr. Scheidt provided sample hypotheses in the handouts but did not review them all in consideration of the time.
Several hypotheses related to vaccines have been proposed. For example, altered timing of early childhood immunizations will lead to no increased rate or severity of disease later in life, and the receipt of childhood vaccination is not linked to autism or other developmental disabilities identified in childhood and adolescence. While some of these have been answered by existing studies, testable data will still be collected and will have greater relative risks than other studies would have been able to afford.
Dr. Scheidt emphasized that the real strength of the study is not necessarily in single exposure outcome relationships, but in the ability to look at the interaction of multiple exposures that may result in multiple outcomes. For example, experience with certain infections early in life might place a certain subgroup at risk so that when they are exposed to a class of chemicals or other exposure, it may result in outcomes that might not otherwise be seen or measurable, unless there was a study that measures multiple outcomes and multiple exposures in the same cohort with a sample size large enough to see the relative risks from interaction analyses.
The measures anticipated for exposures include direct environmental samples (e.g. air, water, and dust); bio-markers for chemicals (e.g. blood, breast milk, hair, and tissue); interview and history data; serology and medical data; housing and living characteristics; family and social experiences; and neighborhood and community characteristics.
The measures anticipated for outcomes include: fetal growth and outcome of pregnancy; birth defects and newborn exam; growth, nutrition, and physical development; medical conditions and history, for which they are looking into capturing electronic medical record data from various sources; cognitive and emotional development; and mental, developmental, and behavioral conditions.
In terms of how the data will be used to maximize output, there will be targeted hypotheses-guided analyses to ensure that the hypotheses will be answered and will be carried out by the investigators involved in the centers carrying out the study, along with the clinical coordinating center and the federal scientists involved in planning the study. In addition, they plan for successive waves of public-use data sets accessible to scientists around the country with anticipated RFAs funded to encourage creative analyses of the data to optimize the use of the data set.
In terms of the projected timeline of the study, they are currently in the phase of carrying out multiple pilot studies, finalizing the plan and design of the study, and finalizing the hypotheses. In the next few months, they anticipate going forward with a clinical coordinating center, procurement of a clinical coordinating center, and the initial vanguard sites where the study will begin and the pilot testing and protocol will occur. They plan to begin the full pilot study and have enrollment in the study by the end of 2006. The preliminary results available from outcomes of pregnancy are anticipated in the 2009 to 2010.
Dr. Scheidt noted that status of the study, updates and newsletters, results of many workshops, review papers undertaken in the planning, and other materials are posted on their website (http://NationalChildrensStudy.gov). He added that they can be contacted with questions at email@example.com.
ACIP/NIP Report - Dr. Myron Levin
Dr. Levin noted that he would be acting for the Acting Director, Dr. Stephen Cochi. He noted that he would only discuss the first two slides since they were the ones with he was most familiar and they give a preview of what would be happening at the upcoming ACIP meeting.
Dr. Levin noted that the major issues to be discussed at the upcoming October 27-28, 2004 ACIP meeting would include a discussion of influenza vaccine supply, coverage, and effectiveness. They will also talk about any headway made in the redistribution of available vaccine and what might be available to deal with the influenza vaccine crisis this year.
There would be a report on the Hospital Infection Control Practitioners Advisory Committee (HICPAC) joint meeting with ACIP on planning a program to improve influenza vaccination of healthcare workers. The documents and brochures for this would be final by the time of the meeting, and there probably would have been quite a bit of progress in this area had there not been a projected shortage. They will hear what plans will be in place to measure vaccine effectiveness for the coming year. He commented that there was some unhappiness last year about how well this was done in the short-run, and they will handle it differently this year.
A large element of the discussion will be the meningococcal conjugate vaccine. There will be a review of what has already been presented, in part, as the background for the use of the vaccine, and for the first time, there will be economic data on whether or not a catch-up program should be added to whatever recommendation is made. ACIP will make a decision on a recommendation for the use of the vaccine at the meeting. He noted, however, that the vaccine may or may not be licensed by the time of the meeting, so it was unclear whether they would be able to vote on it for VFC at the meeting.
After many years, there will be a review of the document to be finalized on the use of the hepatitis B vaccine, and there will be a discussion on whether they will want to extend the recommendations. With respect to the Varicella vaccine, there will be a discussion on breakthrough Varicella and where they are in terms of the success of the vaccine in preventing hospitalizations and deaths in the target population, as well as further data on herd immunity. Since there is breakthrough disease and a proposal for the use of a second vaccine as a booster, there will be data on the immunogenicity, the persistence of the second dose, and the use of MMRV ProQuad, which will be available in the near future. There will also be information on how the working group is planning to make a decision on the use of a booster dose.
Another important element of the ACIP meeting is the proposed evidence-based format for ACIP recommendations. Dr. Dan Fishbein had been very helpful to the working group on this issue. He noted that there would be evidence-based recommendations in the future. The upcoming meeting will be the first introduction of this concept to ACIP and they will be instructed as to what will be available. He added that they may be in a position to make a decision in the spring or summer, that they would adopt this as a formal process at ACIP, and that it would be applied for the first time to one of the new vaccines.
Finally, they will be given an update on the cardiac adverse events of the old smallpox vaccine, as well as an update on the Acambis vaccine. ACIP will then make a resolution to put the smallpox working group aside.
NVPO Report - Dr. Bruce Gellin
The Pandemic Preparedness and Response Plan has been a major project for NVPO for some time, and Dr. Schwartz had taken the lead in working with the other agencies and pulling it all together. They were anxious to get input on the plan, which to date, has been very limited, and the comment period ends at the end of October 2004. He noted that there would be input in a number of ways beyond this comment period and that the plan is an ongoing document that will never be final. They were particularly looking for guidance in areas of the plan that were not as directive as people wanted them to be, as mentioned by Dr. Schwartz, such as the handling of vaccine and the use of antivirals.
There are two RFPs that will be awarded in the coming weeks – one for an egg supply for manufacturers to be able manufacture 24/7 and another to look for incentives to diversify influenza vaccine manufacturing, particularly cell culture. While they have a system in place that can produce influenza vaccine each year, a vaccine that would not require linking to an ongoing circulating strain and that would perhaps have broader protection against a number of different flu viruses would allow a totally different system. Consultants will be working with the vaccine supply group, and they will report on the global influenza vaccine supply industry at the February 2005 NVAC meeting.
Dr. Gellin commented that everything seemed to be about influenza, vaccine supply, or vaccine safety. He noted the previous day’s hearing about the thimerosal content in influenza vaccines and how that might be used. He noted that governor Schwarzenegger signed a bill into law in the last 2 weeks saying that by 2006, children under 3 years of age and women potentially pregnant should not receive vaccines containing anything more than trace amounts of preservative. Given the industry’s move towards this and the concerns about the pace of this, NVPO has been working with CDC and FDA and a long list of partners to understand and plan for transition in the supply. Recognizing that there will be flu vaccine contents with variable amounts of thimerosal over time, they need to think about how this would be best handled. Dr. Gellin noted that his idea of the worst case scenario with the California situation is that people will realize there are two vaccines and see one as clean and the other as dirty, creating an increasing strain on the limited amounts of thimerosal-free vaccines while other vaccines remain on the shelf unused. The management of this type of situation will be an interesting exercise, but they need to try to get everyone involved from the manufacturer to the healthcare community to the public.
|Food and drug administration national institutes of health advisory Committee on: transmissible spongiform||Veterinary medicine advisory committee|
|Ranch hand advisory committee||Medical Devices Advisory Committee|
|Advisory committee on immunization practices||Wildlife Diversity Policy Advisory Committee|
|External Advisory Committee on Cities and Communities||Peer reviewed by the Arizona Department of Commerce Economic Research Advisory Committee|
|Advisory Committee, Cuyahoga Valley School-to-Career Consortium, Broadview Heights, Ohio 1996-2002||Jane D. Siegel, md; Emily Rhinehart, rn mph cic; Marguerite Jackson, PhD; Linda Chiarello, rn ms; the Healthcare Infection Control Practices Advisory Committee|