January 25, 2008
NIH Podcast Episode #0050
Balintfy: Welcome to the 50th episode of NIH Research Radio with news about the ongoing medical research at the National Institutes of Health-the nation's medical research agency. I'm your new host Joe Balintfy. Coming up in this edition, a basic science breakthrough in understanding the genetics of autism; an in-depth interview about a blood disorder; and a report on how scientists can now better predict psychotic illnesses in youth. But first, small steps you can take to prevent diabetes. That's next on NIH Research Radio.
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Small Steps. Big Rewards. Prevent Type 2 Diabetes
BALINTFY: Pre-diabetes is a condition in which a person’s blood glucose levels are higher than normal, but not high enough for a diagnosis of diabetes. Dr. Griffin Rodgers, Director of the National Institute of Diabetes and Digestive and Kidney Diseases says this affects a large portion of the population.
RODGERS: Fifty-four million Americans over age 20 have pre-diabetes, and now this is a condition that increases the risk for developing type-2 diabetes, as the name implies. But it also increases your risk quite substantially for heart disease, and stroke. And within this class of people who are at great risk of either having or developing pre-diabetes, certain ethnic groups, such as African Americans, Hispanics/Latinos, American Indians, Alaska Natives, Asian Americans, and Pacific Islanders, really have an increased risk for developing pre-diabetes and type 2 diabetes.
BALINTFY: Dr. Rodgers points out that there are other situations where a person may be at risk for diabetes.
RODGERS: For example, gestational diabetes occurs in some women during pregnancies and imparts a lifetime risk for them developing diabetes, mostly type-2 diabetes, in both the mother and the child. // Women who are at high risk for developing gestational diabetes or women who have actually developed gestational diabetes can reduce their risk of ultimately developing diabetes by taking small steps for both themselves and their families.
BALINTFY: Dr. Rodgers explains that some of these small steps to lower risk are losing a modest amount of weight, being more physically active, and making healthy food choices every day.
RODGERS: These small steps big rewards that I mentioned are quite simply you aim to lose about 5 to 7 percent of your current weight – so if for example, you weigh 200 pounds that’s only 10 to 14 pounds. And you don’t loose it immediately, you loose it very gradually. You keep a daily log of the food intake your physical activity this is one of the best ways to stay focused on your goals so that you can actually reach these goals. I think a second part is making healthy food choices every day. Choosing healthy foods and snacks for the whole family such as fresh fruit and vegetables, lean sources of protein, low or fat-free milk and cheese products and whole grain breads and cereals are an important way to choose healthy foods. And then taking small steps to be more physically active. Pick fun physical activities the whole family can enjoy such as riding bikes, dancing, or playing tag. You don’t need to join necessarily a costly physical fitness club all you need is a good pair of walking shoes and a comfortable environment to walk 30 minutes a day. If you can’t walk 30 minutes at one stretch, take three ten minutes to walk to get those thirty minutes a day.
BALINTFY: For more information on the Small Steps, Big Rewards Prevent Diabetes Campaign, visit www.YourDiabetesInfo.org or call 1-888-693-6337.
Autism Risk Higher in People with Gene Variant
BALINTFY: Scientists have found a variation in a gene that may raise the risk of developing autism, especially when the variant is inherited from mothers rather than fathers. Researchers at the National Institute of Mental health say they have always known genes are involved with autism…
LEHNER: We just never knew which ones…
BALINTFY: Dr. Thomas Lehner is Chief of the Genomics Research Branch at NIMH.
LEHNER: Now for the first time, we have several studies that find the same findings. That’s very exciting for us.
BALINTFY: Dr. Lehner explains what these findings mean.
LEHNER: The implications would be once we know a gene, hopefully we’ll find others. Because it’s important to point out that there while we have genes, there are probably many genes involved in the etiology of autism and autism itself is a very heterogeneous disorder. Autism is a conglomerate of many subtypes and many genes are probably affecting these subtypes. Now once we know a gene or genes, then we can look at pathways to understand the whole, what we call molecular etiology of a particular disorder. Once we understand all the pathways that lead to a genotype, the hope is, in the future, then we will be able design an intervention. But it’s important to point out that this is still all basic research the future is so far off. But for the first time we actually have a chance of understanding what are the molecular mechanisms that lead to the genotype that we call autism.
BALINTFY: Autism is a brain disorder that impairs basic behaviors needed for social interactions, such as eye contact and speech. The symptoms sometimes cause profound disability, and they persist throughout life. Treatments may relieve some symptoms, but no treatment is fully effective in treating the core social deficits. Dr. Lehner stresses that these latest findings are at a very basic level.
LEHNER: I think what I really want to emphasize is that this is very, very exciting science, but it is basic science. So we cannot expect that there will be treatments coming out this anytime soon. But what is so important about this is that it opens up a toolbox for further research. Once we understand what is the molecular physiology then we can hopefully develop interventions. But at this point, it’s very, very exciting basic research.BALINTFY: For more information about autism, visit the NIMH website at www.nimh.nih.gov.
Balintfy: When we return, we have a feature interview on a rare blood disease.
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Rare Bleeding Disorder: von Willebrand’s Disease
Balintfy: Giving blood is not only important for those that need a transfusion, but for those with a rare blood disorder, it could be the only source for treatment. In this interview, we talked to Dr. Susan Shurin, the Deputy Director of the National Heart, Lung, and Blood Institute at the National Institutes of Health about a bleeding disorder. We asked, what exactly is von Willebrand disease?
Shurin: Well, von Willebrand disease is a disorder of blood clotting. It is usually an inherited disease, almost always an inherited disorder. And people who have Von Willebrand have a tendency to bleed in excess. They often also will have some difficulty in healing wounds so that scars will be left or it will take a long time for tissue to heal.
Balintfy: How often does von Willebrand disease occur?
Shurin: A significant number of people have von Willebrand disease and don’t even know about it. And that happens for a couple of reasons. One is you just may never have the kind of challenge or experience in your life that would make everybody sort of sit up and say, “Gee, that person bled a whole lot too much.” And the other is that in many cases, the bleeding manifestations are hard to determine whether it’s normal or abnormal. Probably the most common situation for this is women who have very heavy menstrual periods.
Balintfy: How exactly is von Willebrand disease diagnosed?
Shurin: It’s diagnosed primarily on the patterns of clotting proteins in the blood. So there’s some very specialized clotting tests that are done. One of the key issues in von Willebrand disease is that it not only is involved in forming a clot within the blood, but it’s also involved in sticking to the platelets which are the first line of defense when you injure yourself or get cut. The first thing that happens is the platelets, which are small fragments of blood cells that are within your blood, will stick to the wall of the blood vessel and plug up the hole. And then von Willebrand factor and some other clotting proteins form the clot that make the nice tight seal so the bleeding really stops and allows the tissues to heal.
Balintfy: What are the treatment options for people with von Willebrand’s disease?
Shurin: …for people who have Type 3 Von Willebrand’s disease, they’re at the most severe forms. Virtually always people end up needing some kind of blood transfusion or factor concentrate to be able to keep the von Willebrand level and the Factor 8 level at a point at which they don’t have serious problems bleeding.
Shurin: For people who have Type 1 of Von Willebrand disease, they may never require any kind of blood product. They may never require either concentrate or any kind of red cell transfusion. But they may need something if they’re having surgery or if they have an injury. So one of the things that’s important is that if you have this, that you know this so that if you’re in something like an automobile accident or something that you come into the emergency room, and they know sooner rather than later that you have a bleeding disorder.
Balintfy: What other treatment guidelines are there for people with bleeding disorders?
Shurin: One of the important things, though, is if you have any kind of bleeding problem of this sort, is that there are a number of preventative things that can be done both to minimize injury. This is not a group of patients we like to have playing hockey, for instance. Usually we’d sort of prefer that they play tennis or go swimming. And also in terms of things like immunizations, people should be immunized against hepatitis, and so that there are a number of approaches that we have to try to minimize the probability that there will be problems. Because as a group, these patients are somewhat more likely, and in some cases, quite a lot more likely to be exposed to blood products. And they’re a lot safer than they ever used to be, but we do try to minimize the potential risk of any kind of blood transfusion, making sure that people are immunized to hepatitis B is one of the important things we do in that kind of situation.
Balintfy: How important are blood donors to people with bleeding disorders like Von Willebrand’s disease?
Shurin: ... Well, one of the key things to keep in mind for many people who have all kinds of bleeding disorders and other kinds of blood disorders as well, but certainly many bleeding disorders is that blood transfusion has been lifesaving for many of those patients. Lifesaving, life changing, and it’s -- one of the key issues about blood transfusions is that this is a gift, that blood transfusion, this is something that is, there’s no other way to get what you get from a blood transfusion. Somebody has to make the altruistic gift of blood donation. And for most people who receive transfusions, a blood transfusion may be the difference between life and death. Sometimes it’s on an acute and immediate basis, say on the battlefield or in the operating room in which if you don’t a blood transfusion right now you’re not going to make it through the day.
Shurin: ... I’m a pediatric hematologist and so most of my patients are children. And the ability of my kids to lead normal lives is really very dependent upon the willingness of people to donate blood. And it’s hard to overemphasize what a gift that is.
Balintfy: For more information on blood diseases and giving blood, please visit the National Heart Lung and Blood Institute website at NHLBI.NIH.GOV. To watch a video of this interview, tune in to our vodcast, “i on NIH”…
Scientist Can Predict Psychotic Illness in Youth
Balintfy: Scientists can predict psychotic illness in up to 80 percent of high-risk youth according to a study by the National Institute of Mental Health. Wally Akinso reports.
AKINSO: Youth who are going to develop psychosis can be identified before their illness becomes full-blown 35 percent of the time if they meet widely accepted criteria for risk, but that figure rises to 65 to 80 percent if they have certain combinations of risk factors. Dr. Robert Heinssen, the study’s principal investigator, breaks down the focus of the study.
HEINSSEN: This study focuses on our ability to predict individuals who are at highest risk for developing a psychotic disorder within a timeframe that actually can inform clinical decision making. So prior to this study the best predictor of who is going to go on to develop psychosis was family history of psychotic illness. If you had a first degree relative that being either a parent or a sibling who had a psychotic disorder, your risk was somewhere between 10 and 12 percent over the course of a lifetime. With this study we use a set of clinical indicators that are evaluated in a structured diagnostic interview and we found that individuals who meet these clinical characteristics have a 35 percent risk of developing psychosis over a 30 month interval. So we’ve been able to triple the predictive accuracy with this new instrument and we’ve been able to clarify the risk window from a timeframe of decades to a timeframe measured in months.
AKINSO: Dr. Heinssen said knowing what the combinations of risk factors are can help scientist predict who is likely to develop the illnesses within two to three years with the same accuracy that other kinds of risk factors can predict major medical diseases.
HEINSSEN: So the criteria that have been tested are the presences of what’s called attenuated positive symptoms. So these would be changes in thinking and communication that would be seen as milder forms of the types of disturbances that we see in active psychosis. So for example unusual thoughts, suspiciousness and paranoia disorganize communication. Those would all be examples. At a given level of severity at a given timeframe, we would say that the person has stepped out of the normal range of experience on these dimensions and now is in a precarious risk state that we would want to monitor carefully to see whether that progressed further. Additional ways that you could be in this risk state are if you had a family history of psychosis similar to what I was describing before. But on top of that you’ve had a significant functional decline over the preceding 12 months. So you’ve experienced noticeable changes in your ability to take care of yourself or to perform your roles as either a student or a worker that would be another root to this.
AKINSO: The other combinations of risk factors that predicted psychosis were past or current drug abuse, and the deteriorating of one’s social functioning. According to Dr. Heinssen research shows that intervention during the early stages of psychosis improves outcomes, but it is not yet clear if even earlier intervention, before a psychotic illness develops, is effective. Dr. Heinssen emphasizes that researchers now have the tool that actually has value for clinical practice today.
HEINSSEN: If a young person presents at a clinic and they are evaluated using the structure diagnostic interview and are found to be in this risk state, what it tells us is that you can treat the symptoms that they present with that have existing therapies associated with them.
AKINSO: Dr. Heinssen added that once researchers identify people as being high risk, they have a very good chance of knowing whether or not they’re likely to develop a serious mental disorder like schizophrenia and that, if they do, it will happen fairly quickly. This is Wally Akinso at the National Institutes of Health Bethesda Maryland.
Balintfy: And that’s it for this episode of NIH Research Radio. Please join us again on Friday, February 8th when the next edition of NIH Research Radio will be available for download. I'm your host, Joe Balintfy. Thanks for tuning in.
NIH Research Radio is a presentation of the NIH Radio News Service, part of the News Media Branch, Office of Communications and Public Liaison in the Office of the Director at the National Institutes of Health in Bethesda, Maryland, an agency of the US Department of Health and Human Services.