October 16, 2009
NIH Podcast Episode #0095
Balintfy: Welcome to the 95th 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. Coming up in this episode, the importance of family history information from a health perspective. Also, important statistics on the prevalence of diabetes, plus ways to control it. But first racial disparities in breast cancer. That's next on NIH Research Radio.
(BREAK FOR PUBLIC SERVICE ANNOUNCEMENT)
Racial Disparities in Breast Cancer Mortality are Not Driven by Estrogen Receptor Status Alone
Balintfy: Recent years have seen an improvement in overall breast cancer mortality rates, but disparities remain between black and white women. Black women experience higher breast cancer mortality rates despite lower incidence rates. Researchers have been studying biological, environmental, and socioeconomic factors, but the underlying cause of this disparity remains unclear. Wally Akinso reports on a recent NIH study that identifies factors for these differences in breast cancer rates.
Akinso: Black women who are diagnosed with breast cancer have a higher probability of dying from the disease than white women.
Menashe: We know that in the last 20 years breast cancer mortality rates are higher in black women than in white women.
Akinso: Dr. Idan Menashe is the lead author of the study and research fellow at in the National Cancer Institute's Division of Cancer and Epidemiology and Genetics.
Menashe: Two major factors having suggested to contribute to this racial disparity. The first one is differences in access to care. The second factor is the biological differences between these two populations.
Akinso: In this study researchers compared breast cancer rates for black and white women using data from the NCI's Surveillance, Epidemiology and End Result program. They used statistical techniques to directly evaluate racial disparities in breast cancer outcomes by examining the rate ratios between black and white women for incidence, morality and hazard rate, as well as performing sub-comparisons by estrogen receptor negative status. Dr. Menashe explains why black women could be at a high risk for breast cancer.
Menashe: We know that black women tend to have higher prevalence of the estrogen receptor negative, or we call it ER negative, tumors which are the more aggressive and more difficult to treat tumors. And therefore people suggest that these differences could account for this racial gap.
Akinso: Researchers found that, from 1990 to 2004, incidence rate ratios remained fairly stable while the breast cancer mortality rate ratios persistently increased. Furthermore, the researchers observed that, regardless of estrogen receptor status, black women with breast cancer were still more likely to die of the disease than white women. Dr. Menashe says because of the data they were able to pinpoint that disparate outcomes between black and white women, particularly in the first few years following breast cancer diagnosis, are the driving factor behind the racial gap.
Menashe: The goal of our study was to explore the underlying causes of the black/white racial disparity in breast cancer mortality in the U.S. We employed different statistical analysis, but particularly we used a statistical approach called an incidence based mortality that allows us to examine the mortality rate according to specific tumor characteristics, for example the differences in ER status.
Akinso: This disparity remained even when the researchers adjusted for age at diagnosis, stage and grade of the tumor, year of diagnosis, and socioeconomic status. When the researchers examined hazard rate trends in black and white women, they noticed that the largest differences occurred in the first three years after diagnosis in both estrogen receptor negative and positive tumors. Dr. Menashe examines the findings.
Menashe: Our construction analyses reveal that the higher prevalence of ER- tumors among black women explain only a small portion of the black/white mortality gap. In contrast, we found out that differences in breast cancer outcome, especially in the first few years following the diagnosis, account for the majority of the disparity. In our analysis we showed that within the first five years after breast cancer diagnosis, black women are twice more likely to die of this disease than white women irrespective of their tumor characteristics.
Akinso: Dr. Menashe hopes that clinicians and other researchers can use the findings to uncover, address, and eliminate the factors for poorer early outcomes for black women. For more information, visit www.cancer.gov. This is Wally Akinso at the National Institutes of Health Bethesda, Maryland.
Panel Assesses Evidence for the Collection and Use of Family Health History Information
Balintfy: Though most Americans are familiar with completing a questionnaire about their family health history when visiting health care providers, an independent panel was convened recently here at NIH to critically assess exactly what we know and what we need to learn about how this process relates to improving health. Anahita Hamidi reports how the panel of experts focused on the use of family history in the primary care setting for common diseases such as diabetes, stroke, cancer, and heart disease.
Hamidi: A person's family history plays an important role in the practice of medicine and has the potential to motivate positive lifestyle changes, enhance individual empowerment, and influence clinical interventions.
Dr. Berg: When you look closely at family history, though, you'll find that there's a lot that we don't know about it.
Hamidi: Dr. Alfred O. Berg is professor in the Department of Family Medicine at the University of Washington in Seattle, and served as Panel Chair for the NIH State-of-the-Science Conference: Family History and Improving Health. Dr. Berg says it is imperative to clarify what is meant by the term "family history."
Dr. Berg: The term is in common use but it really doesn't have a common definition. Clinicians and patients understand it in different ways.
Hamidi: He adds that an increased emphasis on personalized medicine and electronic health records creates a fascinating opportunity to responsibly maximize the value of this information.
Dr. Berg: It's an interesting place to be in medicine right now with a huge increase in the availability of certain kinds of genomic information also with healthcare reform on the horizon a lot interest in electronic health records and in personalizing medical care, so the role that the family history might play in all of this is of obvious interest.
Hamidi: While the correlation between family history and an individual's own health is evident, the various methods by which this information is collected, recorded and analyzed aren't necessarily the most effective.
Dr. Berg: Family history questionnaires are not standardized; they cover a wide variety of factors. The questions may be imbedded in complex risk assessment tools along with other demographic and health factors and even the definition of family varies when you look at it from the perspective of geneticists, generalists, specialists and clinicians, family therapists and members of some ethnic and cultural groups.
Hamidi: The panelists drafted a proposal with twenty-five research recommendations falling under three categories: the structure or characteristics of family history, the process of acquiring a family history and lastly, examining the outcomes of family history acquisition, interpretation, and application.
Dr. Berg: It's been an interesting process. The topic was family history and improving health and of course, many common diseases have genetic, environmental, and lifestyle causes that family members share and healthcare professionals in the U.S. have always asked patients about family history information.
Hamidi: Dr. Berg explains that the interest in examining the role of family health history and its relationship to improving health outcomes is likely reflective of the fundamental changes that modern medicine and science are facing today.
Dr. Berg: But for the most part, the panel found that it is unclear how this information can be effectively gathered and used in the primary care setting for common diseases so our research recommendations outline our suggested approach for addressing the gaps in research.
Hamidi: The panel's complete and updated draft state-of-the-science statement is available at consensus.nih.gov. This is Anahita Hamidi, National Institutes of Health, Bethesda, Maryland.
Balintfy: Coming up next, startling figures on the seriousness of diabetes. Right after this break.
(BREAK FOR PUBLIC SERVICE ANNOUNCEMENT)
How Serious is Diabetes?
Balintfy: In 2007, a total of 1.6 million new cases of diabetes were diagnosed in people 20 years or older in the United States. Another way to look at that statistic is that there were 4,000 new cases of diabetes diagnosed every 24 hours. Where do we stand now? Well we talk to Dr. Griffin Rodgers, director of the National Institute of Diabetes and Digestive and Kidney Diseases, and ask, how prevalent is diabetes among Americans?
Dr. Rodgers: Well, nearly 24 million Americans over the age of 20, or roughly eight percent of the U.S. population, has diabetes. Of these, unfortunately, nearly six million are unaware that they have diabetes. And perhaps more sobering is that there are about 57 million Americans who have a condition called pre-diabetes, and that is their blood sugars are high, higher than normal, but not yet as high to allow for the diagnoses of chemical diabetes.
Balintfy: What are some of the serious complications that are associated with diabetes – in other words, why is this disease so serious?
Dr. Rodgers: Well, heart disease is the number one cause of death among patients with diabetes. In fact, two of three patients with diabetes will die of heart-related disease, either a heart attack or a stroke. Diabetes is the leading cause of kidney failure in the United States for nearly half of the new cases that develop end-stage renal disease. And diabetes is the top cause of adult blindness in this country, and is estimated that between 12,000 and 24,000 new cases exist because of diabetes. And, diabetes is a leading cause of non-traumatic lower extremity amputations in this country.
Balintfy: So what can people with diabetes do to prevent these complications, Dr. Rodgers?
Dr. Rodgers: Well, there’s what we call ABCs of diabetes. The "A" stands for Hemoglobin A1C. Hemoglobin A1C is a measure of your average blood sugar or blood glucose value in the preceding two to three months. And for most patients with diabetes, we like that number to be around seven percent or less. "B" stands for blood pressure, and for patients that have diabetes, we like to get them to manage their blood pressure so that their average blood pressure reading is less than 130 over 80. And the "C" stands for cholesterol, in particular the bad cholesterol, or the LDL cholesterol, and we like to get that number less than 100 where possible.
Keeping the cholesterol, the blood pressure and the A1C at these levels is critically important to prevent or to delay the complications that we mentioned, and as soon as patients are diagnosed with diabetes, getting their blood sugar, their blood pressure and their cholesterol under control is much better in newly onset, because what we’re finding is it’s much easier to prevent these complications than newly diagnosed, in newly diagnosed patients, than in patients that have had the disease for decades or certainly many, many years.
Balintfy: Are there goals that people with diabetes should set to manage their disease?
Dr. Rodgers: Well, in addition to their ABCs, there are other goals that patients can choose to improve the likelihood that these complications don’t set in. For example, physical activity and maintaining physical activity 30 minutes a day on most days, or certainly five days a week, is a good place to start because that tends to maintain the blood sugar in more normal range. Having a sensible eating plan and diet and cutting back on fat-laden foods, having more fresh vegetables and green foods is important. Lean and fresh fish is an important source of proteins that patients can use and thirdly, of course, making certain that the medicines that one is on are being used properly and as indicated by the physician, and again, this is something that it’s important to work very closely with one’s health care provider to make sure that one is on the optimal dose and that the balance between the activity, the diet as well as the medicines, are all aligned properly.
Balintfy: Dr. Rodgers, do you think it’s important for people to have support when it comes to managing diabetes?
Dr. Rodgers: Well, certainly, having friends and family members supporting them in their efforts not only to manage their blood sugars and to remind them that they should test their blood sugars frequently, but also in terms of the food that one eats. If one shares these foods, fresh vegetables, lean meats, the fish and other things, as a family, it’s more likely that people can stick to a more reasonable eating plan. And also, obviously, physical activity, if one has the input and the backing and the positive reinforcement in terms of exercise over each day for a set period of time, it’s more likely that people will stick with these plans moving forward. Of course, any chronic disease is associated with feeling blue and being a little depressed, and getting the family and friends involved in this would certainly act as another way to provide positive reinforcement and get patients through these normal cycles of feeling blue and down on themselves that we all go through and experience.
Balintfy: Thank you Dr. Griffin Rodgers. For more information on diabetes, treatments and research, visit the National Diabetes Education Program-website at www.yourdiabetesinfo.org. And that’s it for this episode of NIH Research Radio. Please join us again on Friday, October 30th when our next edition will be available for download. I'm your host, Joe Balintfy. Thanks for listening.
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.