March of Dimes Birth Defects Foundation National Government Affairs Office 1901 L Street, NW., Suite 260 Washington, DC 20036 Telephone 202 659 1800 Fax 202 296 2964 TESTIMONY OF THE MARCH OF DIMES BIRTH DEFECTS FOUNDATION SUBCOMMITTEE ON HUMAN RESOURCES AND OF THE COMMITTEE ON GOVERNMENT RELATIONS PRESENTED BY Richard Johnston, M.D. Senior Vice President for Programs July 20, 1993 March of Dimes Chairman Towns and Members of the Subcommittee, I am Dr. Richard Johnston, Senior Vice President for Program and Medical Director for the March of Dimes Birth Defects Foundation. On behalf of the March of Dimes, would like to thank you for this opportunity to testify today and commend you for your interest in the role of government agencies in protecting the nation's health. The March of Dimes mission is to improve the health of babies through prevention of birth defects and infant mortality. We carry out that mission through programs of health education, community services, research, and advocacy. Our work is consumer-focused and community-based, using hundreds of thousands of volunteers serving through 115 chapters. Our Foundation also invests in scientific research aimed at discovery of new prevention approaches. I am here to discuss our interest in FDA's Regulation of Dietary Supplements as it relates to folic acid and the potential for birth defects prevention. In the interest of time, I will briefly summarize my testimony and submit the complete text for the record. 1. THERE IS STRONG EVIDENCE IN FAVOR OF USING FOLIC ACID TO PREVENT NEURAL TUBE DEFECTS Neural Tube Defects are a Major Child Health Problem In the United States, there are approximately 60 million women of childbearing age (15 to 44 years), and each year there are 6 million pregnancies and 4 million births. Neural tube defects (NTDs) are birth defects occurring in the brain and spinal cord as they develop in a fetus. Each year in the United States approximately 2,500 babies are born with NTDs. They affect about one in every 1000 births, making these among the most common and severe birth defects. Anencephaly and spina bifida account for 90 percent of NTDs. о In the case of spina bifida (commonly called "open spine") a baby's spinal cord pushes out or never completely closes, resulting in brain damage and paralysis. Spina bifida is a leading cause of paralysis in the United States. Babies with anencephaly are born with a severely underdeveloped brain, and virtually all die in the first days after birth. Over 500 babies die each year from this type of defect. Like most birth defects, NTDs occur in families from every income, age, and racial/ethnic group (See Table 1 for rates by age and race of mother). Women who have previously had one NTD-affected pregnancy are at much greater risk of having another and can be identified for preventive care. However, 95% of women delivering babies with NTDs have no prior history of such birth defects. The incidence of NTDs varies somewhat from area to area. Epidemics have been reported during the 1930s in Massachusetts and currently in China. Because there is no national birth defects surveillance system and most states do not have surveillance programs actively counting cases, we do not know the rate of NTDs for all areas of the country. However, clusters have been reported. For example, an cluster of anencephaly occurred in Brownsville, Texas between 1989 and 1991, and a high incidence has been reported for the Central Valley of California. The Scientific Evidence is Strong During the past decade many studies confirmed a relationship between folic acid intake and birth defects. Published data are available from: randomized controlled trials, 1,2,3 non-randomized intervention trials, 4,5 and observational/case-control studies.6,7,8,9 Only one of these studies found no protective effect. The level of protection found in the other studies ranged from 60% to 86% reduction in risk. In recent years, the quality of the evidence has improved with the results from two randomized, controlled trials.a O O In 1991, the British Medical Research Council reported that 4.0 mg of folic acid prevented the recurrence of NTD-affected pregnancies in 72% of women with a prior history of such defects.2 In 1992, a study in Hungary found that 0.8 mg of folic acid supplements significantly reduced the risk of NTDs. The positive impact was so great that the study was stopped early on the grounds that control-group women Randomized, controlled trials with humans are designed most like laboratory experimental studies and are believed to provide the best quality results. Individuals in the study are assigned to experimental and control groups in a random fashion and do not know to which group they are assigned. ethically should not be denied this effective Half of NTDs Could be Prevented with Folic Acid Over the last 25 years, scientific evidence has been accumulating that consumption of folic acid, a B vitamin, can prevent some NTDs. Because neural tube development is complete by the 28th day of pregnancy, it is important that folic acid is taken in the weeks before conception and early in pregnancy (known as the "periconception period"). The U.S. Public Health Service estimates that at least 50% of NTDs may be averted if all women of childbearing age consume folic acid daily at the 0.4 mg level. This translates into the prevention of birth defects among at least 1,250 infants each year through the implementation of a very simple nutrition/public health intervention. 2. THE U.8. PUBLIC HEALTH SERVICE RECOMMENDS THAT WOMEN CONSUME FOLIC ACID TO PREVENT NTDS In November 1992, the U.S. Public Health Service recommended that all women of childbearing age in the United States consume 0.4 mg of folic acid daily to reduce their risk of having a pregnancy affected by NTDs. (See Attachment A) This recommendation is based on strong scientific evidence demonstrating that supplementary folic acid reduces the frequency of NTDs. The March of Dimes strongly supports this recommendation. The 0.4 mg of folic acid recommended by the Public Health Service to reduce NTDs is also the Recommended Dietary Allowance (RDA). Every adult man and woman should consume this amount daily. However, consumption of folic acid has added protective benefits for women about to begin a pregnancy. The recommendation is targeted to all women of childbearing age who have not had a prior NTD-affected pregnancy because women often do not know they are pregnant until several weeks after conception after the neural tube has developed and closed. Half of pregnant women report that the pregnancy was not planned or expected at the time it occurred. The March of Dimes Birth Defects Foundation views the release of the Public Health Service recommendation as an important opportunity to educate women about the prevention of NTDs through increased consumption of foods rich in folic acid and through vitamin supplements. The Foundation is developing and distributing new public and professional health education materials, and March of Dimes chapters have initiated community-based projects to increase access to folic acid supplements among low-income women. 3. IMPLEMENTATION OF THE PUBLIC HEALTH SERVICE RECOMMENDATION DEPENDS ON FDA ACTION Increasing Folic Acid Consumption through Diet Through careful selection of foods from the U.S. Dietary Guidelines and the Dietary Pyramid women can consume 0.4 mg of folate daily. However, implementation of this recommendation is difficult on standard American diets alone. Folateb obtained from ordinary foods is not as well In the United States, the average daily consumption of folate from diet is estimated to be only 0.2 mg. This means the average woman of childbearing age consumes only half of the RDA and thus half of the amount recommended to reduce her risk of having a baby with an NTD. At the same time, authorization of health claims for foods rich in folate might increase dietary awareness among women of childbearing age. Using Vitamin Supplements to Prevent NTDs Currently, the most direct strategy to implement the Public Health Service recommendation is for all women of childbearing age to take a vitamin pill containing 0.4 mg of folic acid. Consumption of sufficient folic acid through vitamin supplements is relatively easy because most multivitamin preparations available over-the-counter contain the recommended amount. Supplementation as a strategy can be expected to work most effectively for women who understand the need for taking multivitamins, who can afford to purchase them, who are concerned about the risk of NTDs, and who can remember to take the vitamin pill. Moreover, women who are consciously planning a pregnancy are more likely to be motivated to take folic acid supplements on a regular basis. However, as mentioned above, in this country one-half of all pregnancies b Folate is the term used for this vitamin as it is naturally found in foods. |