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QUESTIONS SUBMITTED BY THE SUBCOMMITTEE
Question. Dr. Kupfer, two typical treatments for glaucoma are medications which reduce the pressure within the eye and surgery to accomplish the same purpose. What can you tell us about the
relative effect of these two approaches and the quality of life considerations associated with these two strategies?
Answer. In the United States, the standard approach to the treatment of glaucoma has been to prescribe medications that reduce the intraocular pressure. When medications fail, attempts are made to reduce the intraocular pressure using argon laser trabeculoplasty, followed, if necessary, by filtration surgery. Results from the NEI-supported Glaucoma Laser Trial suggest that argon laser therapy may be a safe and effective alternative to eye drops, as a first treatment for patients with newly diagnosed openangle glaucoma. Another NEI-supported clinical trial of patients with uncontrolled glaucoma has shown that the use of 5-fluorouracil with surgery is more effective in controlling intraocular pressure than filtration surgery alone.
Patients using glaucoma medicines often report serious side effects, including eye irritations, poor vision, fatigue, confusion, loss of appetite, and weight loss. The ophthalmologist attempts to maintain the patient's visual function without causing side effects that might offset the benefits of treatment. No major glaucoma studies have been conducted that specifically measure quality of life as an outcome of treatment decisions. Investigators are currently planning a randomized, clinical trial to evaluate the relative effects of medications versus surgery in managing newly diagnosed glaucoma patients. Quality of life will be assessed in this planned clinical trial.
Question. Dr. Kupfer, it has been known for a long time that the prevalence of glaucoma in the black population is 4 to 5 time more than in the white population in the U.S. What factors lead to this great disparity?
Answer. Although we now have some new data on the magnitude of black/white population differences in the prevalence of glaucoma, we need better information on why these differences exist. Differences in glaucoma prevalence rates reported for whites and for different groups of blacks may be due to genetic influences, variable access to health care, or unknown factors. know that the prevalence of glaucoma reported from studies of blacks living in the United States is less than that of blacks residing in St. Lucia and Barbados. Well-designed epidemiologic studies examining risk factors for the development of glaucoma are needed since few risk factors, other than family history and diabetes, have been identified.
AGE RELATED CATARACT AND MACULAR DEGENERATION
Question. Age related cataract and age related macular degeneration are the major causes of visual impairment and
blindness in the aging U.S. population. I understand that some physicians have already begun to recommend preventative treatments and to treat patients with vitamins and other nutritional supplements to slow or prevent macular degeneration and the development of cataracts. Is this a case of non-traditional medicine leap frogging ahead of conventional practice?
Answer. At present, standard medical practice does not prescribe the use of vitamins or minerals for the prevention of cataract or macular degeneration. There is no convincing evidence that nutritional supplements can affect either the development or progression of these age-related eye conditions. There is a public perception that the use of over-the-counter nutritional supplements may be beneficial in the treatment of a wide range of diseases. This practice carries some risk since many micro-nutrients are toxic at high doses and may give undesirable interactions with drugs of other nutrients.
IMPACT OF NUTRITION ON VISION
Question. What does NEI plan, in terms of clinical trials, to demonstrate the usefulness of vitamins and mineral supplements for prevention and treatment of eye disease?
Answer. The NEI is currently conducting the Age Related Eye Diseases Study (AREDS), which aims to determine how age-related macular degeneration and lens opacities develop and progress. The role of nutrition will be assessed in two ways. First, a natural history study will delineate the role of nutrition as a risk factor for the development of these diseases. Secondly, the feasibility of conducting a randomized, placebo-controlled clinical trial of vitamin and mineral supplements will be evaluated. If such a trial were feasible it would assess the effect of vitamin therapy on the development and progression of lens opacities and age-related macular degeneration.
Question. Dr. Kupfer, I understand that there are at least 10 major/new clinical trials ready to begin in FY 1992 if funds are available. These trials have an estimated total first year cost of $25.1 million and a total cost of $178.6 million. If the Congress provides additional funding to NEI over and above the
Administration request, would funding these new clinical trials be your highest priority?
Answer. The highest priorities of the National Eye Institute include expansion and strengthening of research and related activities for age-related macular degeneration, vision research related to the Decade of the Brain, and glaucoma. These initiatives require both a clinical and basic research focus. Therefore, within each of these initiatives are opportunities for major clinical trials.
Question. Which of these several new clinical trials that are ready to go are your highest priority?
Answer. In priority category order, those clinical trials that are ready to initiate are:
Age-Related Macular Degeneration
Effect of Light Reduction in Retinopathy of Prematurity
Oral vs. IV Intravenous Ganciclovir Retinitis Trial
Assessment of Glaucoma Treatments
Efficacy of Intraocular Pressure Lowering In Ocular
Barbados Glaucoma Treatment Trial
Treatment of Congenital Esotropia
Contact Lens Evaluation in Keratoconus
Low Birthweight & Optic Neuritis
Advanced Retinopathy of Prematurity Study
A NATIONAL VISION RESEARCH PLAN
Question. Dr. Kupfer, I understand that your National Vision Research Plan for 1992 to 1996 is soon to be completed. Could you tell us, in broad terms, the focus this research agenda will have?
Answer. In the National Eye Institute's fourth long-range plan, Vision Research--A National Plan: 1992-1996, the broad focus of the research will be on each of the NEI's major programs-Retinal Diseases, Corneal Diseases, Lens and Cataract, Glaucoma, and Strabismus, Amblyopia, and Visual Processing. In addition, a section of the report will be devoted to Low Vision and Its Rehabilitation and another to Clinical and Epidemiologic Research.
NEW AREAS OF RESEARCH
Question. Are there new areas of research recommended in the National Plan?
Answer. In an effort to identify new areas of research opportunity, panels of experts were established for each of these programs and were charged to: define the scope and impact of important research areas; update program goals and objectives; review current research support and recent scientific advances; and determine the key research questions to be addressed in vision research in FY 1992-1996. These research questions pertain to some of the key new areas of research such as the transplantation of retinal tissues as a potential means of halting or preventing the progressive loss of vision in retinal degenerative diseases. They
also address new opportunities that have been created by recent technological advances in molecular biology and immunology for progress against some of the more perplexing eye diseases.
NUMBER OF RESEARCHERS SUPPORTED
Question. We often get caught up in looking at the number of grants funded, the number of centers funded and the other mechanisms. A more useful measure might be the number of scientists that we support. Has your Institute made an effort to calculate and track the number of scientists that are supported by your funding?
Answer. The Vision Research Program Planning Subcommittee of the National Advisory Eye Council hosted a Policy Planning Forum in August 1989. One of the action items arising from that meeting was a recommendation that a study be conducted to determine trends in NEI research project grants costs and in other grant-related data. Such a study was undertaken and designed to provide baseline information upon which Council funding recommendations and policies could be based. One of the areas selected for study was the size and composition of the research teams funded on NEI research project grants. The results of the study will be published later this year as part of Vision Research A National Plan: 1992-1996. The report will indicate that between 1985 and 1989 there was little change in the total level of staff effort per grant. However, there were definite changes over that time in the staffing patterns of the research team. For example, while there was little, if any, change in the level of efforts of principal investigators, there was an increase in the total level of doctoral-level staff effort per grant, and a decrease in the efforts of research technicians.
Question. Do you think this measure should be implemented NIH-wide so that the Congress and the public would know the number of scientists which are being supported by our research dollars?
Answer. The National Advisory Eye Council has recommended that it is important to examine all mechanisms of research support, not just research project grants, in assessing the overall health of the NIH-supported biomedical enterprise. The Council has stated that other, more broad, indicators of program performance are needed, including the total number and efforts of scientists supported by these diverse mechanisms. In this regard, the NIH has begun, in response to a request in the FY 1992 OMB Passback, an evaluation of the staffing patterns on research project grants. The NEI is participating fully in this data collection effort.
Question. Dr. Kupfer, the average cost of research project grants funded by your Institute has remained well below the NIHwide average for the last 10 years. One of the ways NEI has done this is to not award large program project grants. Your Institute has also been very successful in funding a large percentage of grant applications by holding down costs. As you know, the Congress is considering NIH's Cost Control Plan. Would you care to make any comments on the Plan?
Answer. The NEI has contributed to the development of this plan, and fully supports its objectives. The National Advisory Eye Council and vision research scientists had an opportunity to comment on earlier drafts of the plan and to make recommendations for its improvement. The Council views the Congressional call to action in a very positive way. It finds this approach, when combined with a strategic research planning initiative to address the burgeoning opportunities in biomedical research, fully consistent with its own extensive program planning efforts for vision research.
Question. The entire scientific community very closely watches the number of new grants that are funded each year as a measure of progress being made. Is this the correct measure to follow or should we instead follow the number of scientists who are funded each year as a better indicator of Congressional support of biomedical research?
Answer. The number of new grants funded each year is
certainly important. However, there are other performance measures that seem to me to be even more important. The total number of grants funded (competing and noncompeting) is one such measure. The total number of doctoral-level scientists supported through all mechanisms of grant and contract support, not just research project grants, would seem to be another very important measure. Another useful measure of the overall strength of federally funded biomedical research might be the resources (in constant dollars) ‹ available for research per principal investigator or full-time doctoral level scientist. I am sure that there are other measures that need to be explored, and I think that the NIH plan has indicated that this will be done.
THE OLDEST OLD
Question. Americans age 85 and older (the oldest old) is the fastest growing age segment of the population, and it is felt by some that this group may grow more rapidly than official estimates. Along with this increased longevity comes a decline in vision. What accounts for this correlation?
Answer. Glaucoma, cataract, and age-related macular degeneration are all eye diseases that become more prevalent with advancing age. We remain uncertain, however, as to what specific factors are responsible for the association of age with the development of these chronic eye diseases. We also know that the development of these eye disorders is not solely explained by the aging process. Cigarette smoking, diet, sunlight exposure, diabetes, hypertension, and family history have been shown to be important etiologic factors in the development and progression of these blinding eye diseases in certain populations.
Question. What special initiatives are underway or planned at your Institute to address this concern?
Answer. The NEI has supported a study, conducted in more than thirty nursing homes in the Baltimore area, of the prevalence of ocular diseases in a nursing home population. Information on this population is extremely important in determining its need for eye care and to determine the extent and severity of ocular disorders