October 21, 2011
NIH Podcast Episode #0145
Balintfy: Welcome to the 145th 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 host Joe Balintfy, and coming up in this episode how one part of a Halloween costume comes with three serious risks; will working longer keep your mind sharper; details on the great grandfather of a modern flu virus; and how inefficient stoves contribute to 2 million deaths a year. But first, this news update. Here’s Craig Fritz.
Fritz: Being physically active is vital to maintaining health and independence as we age, and a new federal campaign for people 50 and older will help them to get active and keep going. The Go4Life campaign encourages sedentary older adults to reap health benefits by making physical activity part of their daily lives. Only 25 percent of people aged 65-74 say they engage in regular physical activity. And only 11 percent of people over 85 report being active. Go4Life offers an interactive website providing information and motivation for exercise for individuals, organizations, and health care professionals. The site features specific exercises, success stories, and even offers online virtual coaches to help motivate go4life participants. Researchers say you're never too old to increase your level of physical activity and exercise.
An NIH study has discovered that an anti-HIV drug also stops the spread of the genital herpes virus when used in a vaginal gel form. The drug tenofovir had been demonstrated to inhibit HIV when taken orally, but had not been known to block the genital herpes virus. Researchers say that when using the gel, the amount of tenofovir on the affected tissues is about 100 times the amount in the body than when taken in pill form. That explains why its anti-herpes activity wasn't noticed before. Discoveries leading to new uses for previously approved drugs have the potential to save millions of dollars. New drugs typically undergo years of testing for safety and effectiveness before they are approved for patients. Finding new uses for an approved drug increases the value of the initial investment in testing, because most of the testing has previously been completed.
For this NIH news update – I’m Craig Fritz
Balintfy: News updates are compiled from information at www.nih.gov/news. Coming up we’ll learn about mental retirement, the lasting effects of the 1918 flu, and how people in the developing world, especially women and children, are suffering from inefficient stoves; and an important warning about using decorative contact lenses. That’s next on NIH Research Radio.
(BREAK FOR PUBLIC SERVICE ANNOUNCEMENT)
Decorative contact lenses
Balintfy: Around Halloween time, health experts fear that consumers will harm their eyes with unapproved decorative contact lenses. These are contact lenses that some people use to temporarily change their eye color or to make their eyes look weird—for example, giving them an "eye-of-the-tiger" look. Decorative contact lenses, like any contact lens, come with three serious risks.
Bishop: The first concern of great concern is a corneal infection.
Balintfy: Dr. Rachel Bishop is an ophthalmologist at the NIH. She explains that that any contact lens that’s not handled properly – kept clean and sterile – can produce an infection which can cause vision loss.
Bishop: The second concern is an ill-fitting contact lens. Contact lens that's too tight on the cornea will deprive the cornea of needed nutrients and oxygen and can lead to tight lens syndrome, very uncomfortable, can be quite a problem. So that's avoided by taking proper measurements. The optometrist or ophthalmologist does this.
Balintfy: Dr. Bishop also says a third serious risk, especially for those not used to or trained with putting contacts in or taking them out, is physical trauma.
Bishop: The person can develop a corneal abrasion which is a scratch on the surface of the eye.
Balintfy: Health experts advise that the best way to avoid these risks it to make sure to get lenses only with an eye examination, proper fitting and a prescription from a licensed eye care professional.
Bishop: A person needs to be instructed on how to wear and use the contacts and care for them, and they must be fit properly by someone who knows how to do that, an eye doctor, an optometrist or an ophthalmologist.
Balintfy: Dr. Bishop adds that decorative contact lenses are regulated by the Food and Drug Administration.
Bishop: Whether they're for prescription purposes or for decorative purposes, they're still under the category of regulated medical devices and they should be purchased only at a source that requires a prescription to ensure that they are in fact of a quality that is appropriate for contact lens use on the eye.
Balintfy: She points out that a prescription may indicate that no vision correction for nearsighted or farsighted is needed.
Bishop: The concern, of course, is that people can acquire these with the intention of wearing them for a party or for decoration for a brief period of time, not be properly instructed on how to use them.
Balintfy: With an exam, proper measurements for fitting, and a prescription however:
Bishop: I do think they're fine, but I don’t think it's fine to skip the step of seeing an eye doctor. They really must be treated with the exact same level of concern and diligence as regular contact lenses. They are regular contact lenses. They're just decorated.
Balintfy: Dr. Bishop notes that both those using contact lenses for vision correction and those only interested in decorative contact lenses must balance the risks against the benefits. For more information on eye health and vision research, visit www.nei.nih.gov.
Balintfy: In this next story, we return to a theme that we’ve been covering off and on this year: In 2011, the first wave of baby boomers is reaching the 65-year milestone. For many, that’s retirement age. Others may be planning their retirement or already retired. But an ongoing research study suggests retiring later may have benefits.
Suzman: Staying at work, keeping active, mentally active, helps keep one's cognition sharp.
Balintfy: Dr. Richard Suzman at the NIH explains that a series of studies on health and retirement around the world are showing a pattern.
Suzman: In countries where people retire early, there is a bigger drop in cognitive functioning between say age 55 and 64 than in countries where people can retire later and continue working to an older age.
Balintfy: Countries like France, Italy and Belgium originally conducted research to guide policy decisions on retirement. Dr. Suzman adds that there is more work to do on the recent findings.
Suzman: For example, if people retire and have, you know, very cognitively demanding hobbies or volunteer, will their cognition hold up better than if they're sitting watching TV and doing very little? We just don't know that.
Balintfy: Dr. Suzman agrees that it does make sense that that same way if muscles aren’t used they atrophy or weaken, not using brain function may have a similar result.
Suzman: Other research suggests that, for example, doing crossword puzzles or Sudoku help one improve crosswords puzzles and Sudoku, but it doesn’t generalize to other cognitive activities in everyday living.
Balintfy: Declining ability to perform cognitive activities, those functions that require brain power, are a concern as people age, as much as physical activities.
Suzman: I think when we think about disability, I think we've got to think about both physical disability and cognitive disability. That people need good cognition to carry out the activities of everyday living, making decisions, managing one's money, etc.
Balintfy: And Dr. Suzman points out, this is a growing concern as the population of baby boomers age and the proportion of people over 80 increases.
Suzman: And that population over age 80 is growing enormously.
Balintfy: Dr. Suzman adds that Alzheimer’s disease and dementia have a very high prevalence in the population over age 80. For more information on aging and age-related research, visit www.nia.nih.gov.
NIH scientists find earliest known evidence of 1918 influenza pandemic
Balintfy: From old age to the grandfather of flu viruses. Scientists are learning lessons for future flu outbreaks by carefully examining evidence from past pandemics. Dr. Jeffery Taubenberger, a senior investigator at the NIH explains the importance of studying a flu virus from 1918 that eventually killed 50 million people worldwide.
Taubenberger: We're studying a virus from a hundred years ago because this pandemic, this outbreak in 1918, the Spanish flu was the worst infectious disease outbreak in recorded history that at one short time point, tens of millions of people were killed by this virus. Of course, we want to understand why that happened because we're trying to understand how this virus got going in people and why it caused disease and how it killed people because we think that we can use that information to develop new therapies that could prevent this from happening again.
Balintfy: Dr. Taubenberger says current surveillance systems are a big advantage today, something that would have been helpful a hundred years ago, especially since that flu started earlier than previously thought.
Taubenberger: Influenza was known as a clinical disease in 1918, but they didn't know that it was caused by a virus. They didn't actually even know that viruses existed back in 1918 so there was no way to do surveillance to look for these earlier cases.
Balintfy: Dr. Taubenberger has been studying the genome or DNA of the 1918 flu virus for many years.
Taubenberger: One of the things that we found about the 1918 virus in the last 10 years of the effort to sequence the virus and to study how it behaves is that we think the 1918 virus is very bird-like in its characteristics. So we think that the origin of the virus was actually as a bird virus that somehow this bird virus adapted to humans. Now, we don’t understand the process how that happened. It might have gone through another animal, maybe a pig or some other animal, it may have taken years, but at some point, it acquired all the mutations it needed to be adapted to humans and this pandemic exploded.
Balintfy: More recently Dr. Taubenberger has been examining lung tissue and other autopsy material from 68 American soldiers who died in 1918 before the big outbreak.
Taubenberger: One thing that we unexpectedly found in this recent study were what could be precursor forms of the virus, virus that in a sense might not have been fully adapted to humans.
Balintfy: He says the 1918 flu virus began to circulate in just a few cases during the summer, without an apparent outbreak. Then by the fall of 1918 the virus mutated in a way that made it more infectious for humans. Dr. Taubenberger adds that this recent study also shows that the virus, although lethal, didn’t kill alone.
Taubenberger: We think that in almost all cases in 1918, what actually ended up being the final blow and killing people were bacterial pneumonias. We think that what happened would be that the virus would cause the pneumonia and damage your lung and set you up for a bacterial pneumonia. Most people carry bacteria in their nose, in their throats that are present and generally don't cause disease, sometimes sore throats, but generally not pneumonia. But once the virus did its initial damage, these bacteria were able to sort of take advantage of that situation and then go down and cause a bacterial pneumonia and that was very often lethal back in 1918 and would still be very often lethal today.
Balintfy: He notes that current studies show that if you stop at the viral infection, the lung can rapidly repair itself; but if you add the secondary bacterial pneumonia at just the right time, before the lung repairs itself, the infections together are lethal. Bacterial co-infections were found in all 68 of those American soldiers whose cases were studied. Dr. Taubenberger also points out that the body’s own immune system, which can trigger inflammation or swelling, is also a factor.
Taubenberger: One thing that we have shown and my colleagues around the world have shown in experimental animal models with these virulent influenza virus is like 1918 or the H5N1 bird flu is that they stimulate a really aggressive inflammatory response in a way that we don’t quite understand. But we think that the immune response itself actually contributes to the damage and so it's likely that that's actually another big component of why these viruses kill people.
Balintfy: He says understanding and perhaps modifying the way that immune response occurs may lead to new therapies, even for old viruses. Dr. Taubenberger explains that the 1918 pandemic was caused by an H1N1 flu virus, perhaps the great-grandfather of the 2009 H1N1 pandemic.
Taubenberger: So in a sense the impact of the 1918 virus is not measured just in the tens of millions of people who died in the first year in 1918, but actually in all influenza infections both seasonal and pandemic that have occurred since then. They're all descendants of the 1918 flu.
Balintfy: It being flu season now, Dr. Taubenberger reminds:
Taubenberger: Hands down, the absolute best way to prevent and deal with influenza is vaccination. Vaccination is an extremely important and essential public health tool not only for individual safety but to decrease the spread of the virus to the most susceptible in our population.
Balintfy: For more information on flu viruses and recent studies involving the 1918 pandemic, visit www.niaid.nih.gov. And coming up, everyone’s heard of the flu, but what about indoor pollution as a common killer? That’s next on NIH Research Radio.
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Inefficient stoves contribute to 2 million deaths a year
Balintfy: The flu is an infectious disease. Other infectious diseases include malaria, tuberculosis and HIV/AIDS. Another category of diseases is non-communicable or chronic diseases, like heart disease, lung disease and cancer. Some of these can be caused not by a virus or infection, but an environmental factor. For example, exposure to cigarette smoke causes cancer.
Collins: You might ask what is the most significant cause of death from environmental exposures that you've never heard of.
Balintfy: That’s NIH Director, Dr. Francis Collins.
Collins: And it turns out that it is exposure to air pollution inside the home because close to because close to three billion people on this planet are exposed to cooking fire smoke because of the way in which their homes are set up so that cooking is done over an open fire without ventilation.
Balintfy: Dr. Collins is co-author on a commentary in Science magazine explaining that almost two million people a year die as a consequence of that indoor air pollution exposure.
Martin: As a pulmonary physician I find these numbers staggering.
Balintfy: That’s Dr. William Martin; he’s the lead author on the article. He points out that these are more deaths than occur globally from malaria or tuberculosis and are equivalent to as many deaths from AIDS.
Martin: Although there are many health effects from this household pollution, the World Health Organization currently only attributes three causes for the global mortality from this exposure nearly two million deaths a year. One, almost a million deaths every year occur in children under the age of five who die from acute lower respiratory tract infections that is acute pneumonia; secondly, almost a million deaths occur in women from chronic obstructive pulmonary disease more commonly known as COPD; and third, lung and upper airway cancers that also occur mostly in women but who do not often have significant tobacco smoke exposure.
Balintfy: Dr. Collins notes these are all preventable diseases.
Collins: But the solution is complicated. It involves technology. It involves cultural changes and education. It involves, of course, global health because most of these circumstances are in places in the world where incomes are very limited and the resources for inducing change are therefore much more difficult to come by.
Martin: Picture yourself anywhere in the world where there is severe poverty, where people live on an equivalent of a dollar a day or less. They may be living in small huts or households that barely protect them from the elements and yet like all of us they must cook their food, heat their homes, and seek light when it is dark outside. All of this typically requires burning a fuel. And for those who are extremely poor, the fuel may be wood, charcoal, crop residues, or even animal dung.
Balintfy: Dr. Martin explains that part of this complicated problem of indoor or household air pollution is related to efficiencies: both fuel efficiency – getting more fire from the same fuel – and combustion efficiency – getting a hotter fire that burns off more smoke particles.
Martin: In science we always look for technology to answer questions and solve health problems in particular. And science it's critically important. I mean the technology advancement in affordable cook stoves has been amazing in the past five years and changes almost daily. However, you could give the most advanced stove to a family and if they use as their fuel leaves or twigs that have been picked up along the side of the road you will still get a smoke bomb.
Collins: We need to learn many things about how to change this.
Balintfy: Again Dr. Collins. He explains that the United Nations Foundation has launched the Global Alliance for Clean Cookstoves to try to coordinate a research effort to figure out, for example, how much do you have to reduce exposure in order to prevent pneumonia deaths in children or lung problems in adults?
Collins: We've conducted one very important seminal study in Guatemala called the RESPIRE study which did look rather in a rigorous way at what happens when you offer to individuals an opportunity to substitute what they've been doing for cooking with a kind of technology that allows for better ventilation and better efficiency. We also include in that monitoring of the home to determine exactly what has happened as far as reduction and exposure; and it looks as if unless you can reduce the exposure by at least 50% you are not going to achieve the health benefits.
That says that if you're going to institute a big effort and we want to see that happen in the Global Alliance for Clean Cook Stoves with much encouragement from Hilary Clinton has made this goal of a 100 by 20 which is 100 million homes with new clean cook stoves by 2020. If you're going to do that, you better be sure that you have done so in a way that's really going to have the health impact we all believe in. And NIH has a big role to play there.
So we will be investing in those kinds of research studies. We'll look at better technologies to be able to do monitoring cheaply and effectively, we'll look at new kinds of technologies for stove manufacture that can be cost-effective because this obviously have to be quite inexpensive considering the parts of the world that need it the most, and we'll look at the cultural and behavioral practices because unless we can convince the communities that are most involved that this is something they want to do it would be difficult to change practices that may have been going on for decades or even centuries.
That's a fascinating combination of research problems all wrapped up in this particular area but one with great potential to save lives maybe even two million lives a year. By the way, that's more people that die of malaria every year; and here it is from a problem that most people haven’t heard about.
Balintfy: Dr. Martin though, comments that this is his life.
Martin: I am so committed to this partly because I'm a pulmonary physician, partly because I am at this later stage in my career and I came to this understanding of this risk really just 6-7 years ago. And so, for me it's very personal and I think because of the new technology and stoves and fuels for the first time we can really do something about it.
Balintfy: And that’s it for this episode of NIH Research Radio. Please join us again on Friday, November 4 when our next edition will be available. If you have any questions or comments about this program, or have story suggestions for a future episode, please let me know. Best to reach me by email—my address is email@example.com. I'm your host, Joe Balintfy. Thanks for listening.
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