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Newswise — DALLAS – Oct. 25, 2011 – A simple blood test could someday quantify a smoker’s lung toxicity and danger of heart disease, researchers at UT Southwestern Medical Center have found.

Nearly one in five adults in the U.S. smoke, and smoking-related medical expenses and loss of productivity exceeds $167 billion annually, according to the Centers for Disease Control and Prevention. Levels of a lung protein found in the blood of smokers could indicate their risk of dangerous plaque buildup in blood vessels, said Dr. Anand Rohatgi, assistant professor of internal medicine at UT Southwestern and co-lead author of the study available in Arteriosclerosis, Thrombosis, and Vascular Biology, a publication of the American Heart Association.

“We now are close to having a blood test to help measure the smoking-related effects that contribute to atherosclerotic heart disease,” Dr. Rohatgi said. “Smoking is one of the biggest contributors to the development of heart disease.”

Smokers are at an increased risk of heart attack, stroke and dying from heart disease, but the risk varies among individuals. Until this study, there had been no simple blood test to measure the varied effects of smoking on heart disease.

Researchers determined the amount of circulating pulmonary surfactant B (SP-B), a protein found in damaged lung cells, in more than 3,200 Dallas Heart Study participants ages 30 to 65. The Dallas Heart Study was a groundbreaking investigation of cardiovascular disease that first involved more than 6,100 Dallas County residents who provided blood samples and underwent blood vessel scans with magnetic resonance imaging and computerized tomography.

The researchers found that smokers who had higher levels of SP-B also had more buildup of dangerous plaque in the aorta – the largest artery in the body, with branches leading to the abdomen, pelvis and legs.

The test is still being evaluated and is not available for commercial use. The next step, said Dr. Rohatgi, is to investigate whether SP-B causes atherosclerosis or is simply a marker of the disease, and to determine whether decreasing levels of SP-B will improve heart disease outcomes.

Other UT Southwestern researchers involved in the study were co-lead author Dr. Ann Nguyen, resident in internal medicine; Dr. Christine Garcia, assistant professor in the Eugene McDermott Center for Human Growth and Development and in internal medicine; Colby Ayers, faculty associate in clinical sciences; Dr. Sandeep Das, assistant professor of internal medicine; Dr. Susan Lakoski, assistant professor of internal medicine; Dr. Jarett Berry, assistant professor of internal medicine; Dr. Amit Khera, associate professor of internal medicine; Dr. Darren McGuire, associate professor of internal medicine; and Dr. James de Lemos, professor of internal medicine.

The study was funded by the Donald W. Reynolds Foundation and the National Institutes of Health. Alere provided assay measurements.

Innovative UK technology is contributing to the development of a revolutionary digital stethoscope that could make it easier for GPs to spot the first signs of heart disease.

With Engineering and Physical Sciences Research Council (EPSRC) funding, a Queen Mary, University of London (QMUL) team has developed a computer-based technology that synchronises the various sounds collected by the new stethoscope and which make up a human heartbeat.

The sounds can then be analysed by an existing technique called ICA (independent component analysis), with data presented on a laptop or desktop computer in easy-to-understand graphs. These provide a visual representation of the heartbeat and any anomalies in it. Currently, such anomalies can be missed by doctors who aren’t experts in cardiac care.

ICA can only analyse heartbeats if all the different sounds that make up an individual’s heartbeat are brought together as one overall sound.

Like a conventional stethoscope, the new stethoscope captures four sounds one after another. The computer-based technology developed by the QMUL team then turns these separate sounds into one combined signal which ICA can then process. The QMUL synchronisation technology therefore plays a vital bridging role between the new stethoscope and ICA.

With conventional stethoscopes, the identification of a potential heart problem is completely reliant on the expertise and listening skills of the GP.

QMUL’s technology was unveiled on 25th May at the 36th International Conference on Acoustics, Speech and Signal Processing held in Prague in the Czech Republic.

The overall stethoscope development project is an international collaboration led by Portugal’s University of Porto and Centro Hospitalar Alto Ave, Guimarães.

“Heart disease is still the UK’s number-one killer”, says Professor Mark Plumbley, who has led the QMUL work. “Our work here is making a vital contribution to an invention that will help GPs identify heart problems before they become serious – even when patients come to surgery about a totally unrelated health matter. Early interventions not only help patients but also reduce the burden on healthcare resources.”

As well as being suitable for use in GP surgeries, the stethoscope – called the DigiScope – will be ideally suited to outpatient clinics, accident & emergency units and other hospital departments where doctors are not necessarily cardiac specialists.

The DigiScope is designed to be used by doctors in exactly the same way as they use a conventional stethoscope. They position the end piece, in turn, on four different places on the patient’s chest. However, with the DigiScope these four separate sounds are then transmitted wirelessly to a laptop or desktop and synchronised by the QMUL technology as if they were all transmitted simultaneously. They are then analysed using ICA.

With the new system, doctors can compare the visual graphs produced with ‘normal’ readings while the patient is there, or save the graphs and study them later. Or a second opinion on the data can be obtained, via the internet, from another doctor located miles away.

“It’s the multidisciplinary character of this exciting international collaboration that has enabled it to produce such a promising outcome,” says Professor Plumbley. “Two prototype DigiScopes are already in use to test their capabilities. The development will not remove the need for specialist cardiac units, it will simply make it easier to identify potential heart problems at an earlier stage.”

Notes for Editors

The overall DigiScope initiative is a three-year, £120,000 project funded by the Fundação para a Ciência e Tecnologia (the Portuguese equivalent of the EPSRC).

The project is benefiting from additional co-operation from Brazil’s Real Hospital Português in Recife.

The QMUL work has been undertaken as part of the 5-year ‘Machine Listening Using Sparse Representations’ project, which is receiving EPSRC funding of just over £1.2M.

About the DigiScope: in the ears of an experienced physician, a stethoscope yields important clinical information which can help an initial assessment of a patient’s clinical condition and guide the subsequent need for more specialised examinations. This is particularly true in chest medicine (i.e. cardiology and pneumology), which is the reason why stethoscopes still maintain a key position in medicine in the modern era. However, auscultation (listening to internal sounds within the body via a stethoscope) is a hard skill to master. Heart sounds are of low frequency and the intervals between events are in the order of milliseconds, requiring significant practice for a human ear to distinguish the subtle changes between a normal and a pathological heart sound. The use of a digitally enhanced stethoscope, to train physicians to improve their basic skills in diagnosing and treating heart conditions, or as a tool for worldwide screening of specific heart pathologies, is an example of how state-of-the-art technology can be used to benefit people whatever socio-economic group they belong to and wherever they live. This drives the key objective of the DigiScope project: to develop the prototype of a digitally enhanced stethoscope, capable of automatically extracting clinical features from the collected data as well as providing a clinical second opinion on specific heart pathologies. The Principal Investigator is Miguel Tavares Coimbra, Assistant Professor in the Faculty of Science at the University of Porto. For more information see www.digiscope.up.pt

New research published on bmj.com today adds to mounting evidence that calcium supplements increase the risk of cardiovascular events, particularly heart attacks, in older women.

The findings suggest that their use in managing osteoporosis should be re-assessed.

Calcium supplements are often prescribed to older (postmenopausal) women to maintain bone health. Sometimes they are combined with vitamin D, but it’s still unclear whether taking calcium supplements, with or without vitamin D, can affect the heart.

The Women’s Health Initiative (WHI) study – a seven-year trial of over 36,000 women – found no cardiovascular effect of taking combined calcium and vitamin D supplements, but the majority of participants were already taking personal calcium supplements, which may have obscured any adverse effects.

So a team of researchers, led by Professor Ian Reid at the University of Auckland, re-analysed the WHI results to provide the best current estimate of the effects of calcium supplements, with or without vitamin D, on the risk of cardiovascular events.

They analysed data from 16,718 women who were not taking personal calcium supplements at the start of the trial and found that those allocated to combined calcium and vitamin D supplements were at an increased risk of cardiovascular events, especially heart attack.

By contrast, in women who were taking personal calcium supplements at the start of the trial, combined calcium and vitamin D supplements did not alter their cardiovascular risk.

The authors suspect that the abrupt change in blood calcium levels after taking a supplement causes the adverse effect, rather than it being related to the total amount of calcium consumed. High blood calcium levels are linked to calcification (hardening) of the arteries, which may also help to explain these results.

Further analyses – adding data from 13 other trials, involving 29,000 people altogether – also found consistent increases in the risk of heart attack and stroke associated with taking calcium supplements, with or without vitamin D, leading the authors to conclude that these data justify a reassessment of the use of calcium supplements in older people.

But in an accompanying editorial, Professors Bo Abrahamsen and Opinder Sahota argue that there is insufficient evidence available to support or refute the association.

Because of study limitations, they say “it is not possible to provide reassurance that calcium supplements given with vitamin D do not cause adverse cardiovascular events or to link them with certainty to increased cardiovascular risk. Clearly further studies are needed and the debate remains ongoing.”

AURORA, Colo. (March 25, 2011) – In one of the most comprehensive studies of its kind, researchers at the University of Colorado School of Medicine in partnership with the Harvard School of Global Health have found that people living at higher altitudes have a lower chance of dying from ischemic heart disease and tend to live longer than others.

“If living in a lower oxygen environment such as in our Colorado mountains helps reduce the risk of dying from heart disease it could help us develop new clinical treatments for those conditions,” said Benjamin Honigman, MD, professor of Emergency Medicine at the CU School of Medicine and director of the Altitude Medicine Clinic. “Lower oxygen levels turn on certain genes and we think those genes may change the way heart muscles function. They may also produce new blood vessels that create new highways for blood flow into the heart.”

Another explanation, he said, could be that increased solar radiation at altitude helps the body better synthesize vitamin D which has also been shown to have beneficial effects on the heart and some kinds of cancer.

The study was recently published in the Journal of Epidemiology and Community Health.

At the same time, the research showed that altitudes above 4,900 feet were detrimental to those suffering from chronic obstructive pulmonary disease.

“Even modestly lower oxygen levels in people with already impaired breathing and gas exchange may exacerbate hypoxia and pulmonary hypertension [leading to death],” the study said.

Honigman, senior author of the study, along with researchers that included Robert Roach, PhD, director of the School of Medicine’s Altitude Research Center, Deborah Thomas, PhD, a geographer at the University of Colorado Denver and Majid Ezzati of the Harvard School of Global Health, spent four years analyzing death certificates from every county in the U.S. They examined cause-of-death, socio-economic factors and other issues in their research.

They found that of the top 20 counties with the highest life expectancy, eleven for men and five for women were located in Colorado and Utah. And each county was at a mean elevation of 5,967 feet above sea level. The men lived between 75.8 and 78.2 years, while women ranged from 80.5 to 82.5 years.

Compared to those living near sea-level, the men lived 1.2 to 3.6 years longer and women 0.5 to 2.5 years more.

Despite these numbers, the study showed that when socio-economic factors, solar radiation, smoking and pulmonary disease were taken into account, the net effect of altitude on overall life expectancy was negligible.

Still, Honigman said, altitude seems to offer protection against heart disease deaths and may also play a role in cancer development.

Colorado, the highest state in the nation, is also the leanest state, the fittest state, has the fewest deaths from heart disease and a lower incidence of colon and lung cancer compared to others.

“We want to now look at these diseases in a more focused way so we can see the mechanisms behind hypoxia and why they affect the body the way they do,” Honigman said. “This is a public health issue in Colorado and the mountain West. We have more than 700,000 people living at over 7,000 feet above sea level. Does living at altitude change the way a disease progresses? Does it have health effects that we should be investigating? Ultimately, we hope this research will help people lead healthier lives.”

Researchers say strategies do not consider ethnicity, a leading risk factor for heart disease

TORONTO, Ont., March 17, 2011 — Major clinical studies that evaluate prevention strategies for heart disease and stroke fail to consider a participant’s ethnicity, a factor that can more than double the rate of death in some groups, according to research led by St. Michael’s Dr. Joel Ray.

The study, published online in the Quarterly Journal of Medicine, reviewed 45 major clinical trials on prevention strategies. Researchers found that only 1 in 4 studies reported on the ethnicity of participants. None included information about whether a participant was an immigrant. When ethnicity is reported, it is often superficial in scope.

“On the one hand, some immigrant groups to Canada have lower rates of chronic diseases than Canadian-born residents,” Ray explains. “But, at the same time, some ethnic groups — like those from South Asia, including India and Pakistan — have dramatic early onset of heart disease and stroke. And, not all ethnic groups respond to preventive treatments in the same manner, such blood pressure medications among persons of Afro-Caribbean decent.”

In Canada, 17 per cent of citizens are of a visible minority. Heart disease costs accounts for 17 per cent of hospitalizations each year. Rates of heart disease and stroke are highest among South Asians, one of the largest and fastest growing ethnic groups in Canada, the USA and the U.K. South Asian immigrants have up to a four times higher risk of death from heart disease compared to native-born populations.

“This makes it important to consider ethnicity when conducting research studies so that we can better target prevention strategies to different ethnic groups,” says Ray.

The researchers say some ethnic groups may also be reluctant to enrol in clinical trials because consent forms tend to be in English and French. Others may shy away from committing to participating in research because of cultural norms, they add.

“Most of our scientific research on heart disease and prevention stems from studies conducted in the industrialized world, and among predominantly White populations,” Ray said. “Future studies must both recruit and report on ethnic and immigrant status of their study groups to ensure we are treating these patients in the best way possible. This must become a priority concept for researchers and funding agencies such as the Canadian Institutes of Health Research and the Heart and Stroke Foundation of Canada.”

HOUSTON, TX–(Marketwire – February 22, 2011) – SHAPE, The Society for Heart Attack Prevention and Eradication (http://www.shapesociety.org), a nonprofit organization that promotes early detection and preventive intervention to eradicate heart attacks, today issued a letter to the Circulation Journal and the New England Journal of Medicine expressing concerns about the 2011 update to the American Heart Association’s guideline for the prevention of cardiovascular disease (CVD) in women.

By arbitrarily lowering and deflating the cut-off point for the High Risk category from 20 percent to 10 percent and continuing to rely solely on traditional risk factors to measure an individual’s risk, the new guideline could result in massive overtreatment and undue “High Risk” labeling of many otherwise healthy women.

“The primary reason our existing national CVD prevention guidelines do not work in women is not because the guidelines have a high threshold but because they are based on less than precise measures of the disease,” said Dr. PK Shah, chairman of the SHAPE Scientific Board who is also a Professor of Medicine at UCLA and Director of Cardiology at Cedars-Sinai Heart Institute and Medical Center in Los Angeles. “Measuring traditional risk factors alone is not enough to characterize atherothrombotic risk especially in intermediate risk cohorts. Such patients could benefit from a more individualized risk assessment when measures of subclinical atherosclerosis are included in the risk prediction strategy.”

Existing guidelines inexplicably hesitate to exploit the full benefit of testing for subclinical atherosclerosis in the primary prevention of CVD. This is the missing piece.

“To prevent massive overtreatment and undue ‘high risk’ labeling of healthy women, SHAPE is urging the new AHA guideline be amended to incorporate the responsible use of scientifically proven noninvasive tests for subclinical atherosclerosis,” said Erling Falk, M.D., Ph.D., chief of the SHAPE Task Force II Editorial Committee, who is also Professor of Cardiovascular Pathology at Aarhus University Hospital in Denmark.

The SHAPE Task Force encourages physicians to use either coronary artery calcification scoring (CACS) by a CT scan or carotid artery intima-media thickness (CIMT) and plaque scanning by ultrasound. By implementing screening for asymptomatic atherosclerosis in women age 55 and older who have a Framingham Risk Score of six percent or greater, physicians can significantly improve their risk assessment and take appropriate preventive measures.

By relying solely on traditional risk factors, the new guideline also contradicts the recommendations in the “2010 ACCF/AHA Guideline for Assessment of Cardiovascular Risk in Asymptomatic Adults,” in which testing for subclinical atherosclerosis through CACS or CIMT received a strong evidence-based (Level IIa) recommendation.

“While we laud the intentions of the revised AHA guideline, SHAPE believes that the best way to accurately determine an individual’s risk for atherosclerotic cardiovascular events is to encourage them to have an atherosclerosis test,” said Mathew Budoff, M.D., Professor of Medicine at the David Geffen School of Medicine at UCLA.

About SHAPE
Based in Houston, the Society for Heart Attack Prevention and Eradication (SHAPE) is a non-profit organization that promotes research and education for early detection and treatment of healthy-looking individuals who are at risk of a future heart attack or stroke. SHAPE is committed to raising public awareness about revolutionary discoveries that are opening exciting avenues to prevent, treat and ultimately eliminate atherosclerotic cardiovascular disease. SHAPE’s mission is to eradicate heart attacks in the 21st century. Additional information is available on the organization’s website at www.shapesociety.org

Older patients are willing to take medications for cardiovascular disease prevention, but only if the drug has much more benefit than risk, according to a report published online first by the Archives of Internal Medicine, one of the JAMA/Archives journals. The paper will be published in the June 27, 2011 print issue of the journal.

“Quality-assurance and pay-for-performance initiatives increasingly encourage adherence to evidence-based guidelines for the prevention or management of particular diseases,” the authors provide as background information in the article. “However, guideline-directed therapy may be at odds with the preferences of the patients who are targeted by the guidelines.” The authors note that many older patients have multiple risk factors for chronic disease and may not value the guidelines in the same way as clinicians when they consider benefits and harms of medications.

Terri R. Fried, M.D., of Yale University School of Medicine, New Haven, Conn., and the VA Connecticut Healthcare System, and colleagues examined the willingness of older adults to take medications for primary cardiovascular disease prevention according to benefits and harms. For this study, 356 in-person interviews were performed with community-living older persons (average age, 76). The participants were asked about their willingness to take medication for primary prevention of heart attack (myocardial infarction). The medication was described as reducing the participant’s risk of having a heart attack over the next five years, but with various types and severity of adverse effects, including fatigue, dizziness, nausea and fuzzy or slowed thinking.

Most participants (88 percent) indicated they would take the medication if it had no adverse effects, providing an absolute benefit of six fewer persons with heart attack out of 100, approximating the average risk reduction of currently available medications. “As the absolute benefit offered by the medication increased, so did the proportion willing to take the medication,” the authors note. “In contrast, large proportions (48 percent to 69 percent) were unwilling or uncertain about taking medication with average benefit causing mild fatigue, nausea, or fuzzy thinking, and only 3 percent would take medication with adverse effects severe enough to affect functioning.”

“The central finding of this study was the large influence exerted by the presence of adverse effects on older persons’ decisions about whether to take a medication,” the authors write. “These results suggest that clinical guidelines and decisions about prescribing these medications to older persons need to place emphasis on both benefits and harms,” they conclude.

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Editor’s Note: This study was supported by a grant from the Robert Wood Johnson Foundation and by the Claude D. Pepper Older Americans Independence Center at Yale University School of Medicine. Dr. Fried is supported by a grant from the National Institutes of Health/National Institute on Aging.

What Your Legs Could Be Telling You About Your Heart Health

Approximately nine million Americans over the age of 50 are living with a disease that affects their legs and raises their risk of having a heart attack. Unfortunately, many with the disease do not even know they have it. February is Heart Month, and the Vascular Disease Foundation and its P.A.D. Coalition are urging Americans to listen to their legs and be alert to the signs of peripheral arterial disease, or P.A.D.

P.A.D. occurs when arteries in the legs become narrowed or clogged with fatty deposits, reducing blood flow to the legs. This can result in leg muscle pain when walking, disability, amputation, and poor quality of life.  If you have blocked arteries somewhere in the body, you are likely to have them elsewhere. Thus, P.A.D. is a red flag that other arteries, including those in the heart, are likely affected – increasing the risk of a heart disease, heart attack and even death.

In many, P.A.D. is a silent disease, causing no recognizable symptoms. People with P.A.D. may have one or more of the following symptoms:

* “Claudication” – fatigue, heaviness, tiredness or cramping in the leg muscles (calf, thigh or buttocks) that occurs during activity such as walking and goes away with rest.
* Foot or toe pain at rest that often disturbs sleep
* Skin wounds or ulcers on the feet or toes that are slow to heal (or that do not heal for 8 to 12 weeks).

“Often, people think leg discomfort or slow healing sores are just a part of aging, yet they can be signs of a serious disease,” stated Joseph Caporusso, DPM, Chair of the P.A.D. Coalition. “Through early detection and proper treatment, we can reduce the devastating consequences of P.A.D. and improve the nation’s cardiovascular health.”

Everyone over age 50 is at risk for P.A.D., and your risk increases if you:

Smoke, or used to smoke

Have diabetes

Have high blood pressure

Have abnormal blood cholesterol

Are African American

Have a personal history of coronary heart disease or stroke

The screening test for P.A.D. is called the ankle-brachial index, a painless, non-invasive test that compares the blood pressure in the ankles with the blood pressure in the arms. National medical guidelines recommend that certain individuals be tested for P.A.D., including:

Adults under 50 years of age with diabetes and at least one other risk factor such as a history of smoking, abnormal cholesterol or high blood pressure

Adults aged 50 years or older with diabetes or a history of smoking

Adults aged 70 years or older

Adults with one or more symptoms of P.A.D.

If you fit into any of the above groups, talk to your health care provider about being tested for P.A.D.

Drinking Diet Soda Daily Linked to Heart Disease

FOR IMMEDIATE RELEASE

PRLog (Press Release) – Feb 23, 2011 – Diet soda sweetened with artificial sweeteners has been under the gun lately. Some say they are bad for you; others that they are harmless. One company says that diet soda could help you to lose weight by cutting out sugar. Then a report comes out that says these same products are likely to increase your appetite and cause you to gain weight. It seems scientists still haven’t reached a consensus about how beneficial (or harmful) diet soda may be. More proof for the naysayers has just arrived, however. According to a new study, drinking lots of diet soda can up your risk for heart disease.

Researchers at the University of Miami Miller School of Medicine discovered that there was a significant increased heart disease risk among those who drank diet soda daily — but not with those who drank regular soda.

The research team evaluated the soda habits of 2,564 people enrolled in the large Northern Manhattan Study (NOMAS) to see if there was an association, if any, with stroke. The participants were 69 years of age, on average, and completed food questionnaires about the type of soda they drank and how often.

During the average nine-year follow-up, 559 vascular events occurred, including strokes caused by hemorrhage and those caused by clots, known as “ischemic strokes.”

The researchers were careful to account for such factors as age, gender, ethnicity, physical activity, calorie intake, smoking and alcohol drinking habits, but still came up with the same results: those who drank diet soda daily were 61% more likely to have a heart event.

The researchers even went one step further. They checked for the presence of metabolic syndrome, vascular disease in the limbs, and heart disease history. The link between diet soda and heart disease still held, albeit at a somewhat lower 48%.

The researchers were unable to determine why diet soda was linked to heart disease. Previous research by others has suggested that those who drank more than one soft drink a day, whether regular or diet, were more likely than non-drinkers to have metabolic syndrome. Metabolic syndrome, in turn, raises the risk of diabetes and cardiovascular disease, experts agree.

So what can you do if diet soda seems the better alternative to regular soda when it comes to calories? Just remember that diet soda, like most things, should be drunk in moderation. Try substituting water if you find yourself reaching for a can more than once or twice a day. And if water doesn’t do the trick, try green or black tea, fruit juice, or sparkling water with a little lemon or lime added. You might just be protecting your heart.