Steroids Could Harm Heart's Pumping Ability
TUESDAY, April 27 (HealthDay News) -- Long-term use of anabolic steroids weakens the heart more than had been thought, a new study of weight lifters shows.
The study provides what might be the first clear evidence that these muscle-building drugs, used widely by bodybuilders and athletes, can damage heart function, said Dr. Aaron L. Baggish, an assistant in medicine at Massachusetts General Hospital, and lead author of a report on the study published online April 27 in Circulation: Heart Failure.
"There have been mixed assumptions but very little direct scientific study of what happens to the heart when it is exposed to an anabolic steroid, and none of what happens with chronic use," Baggish said.
Anabolic steroids, which mimic the muscle-building effects of the male hormone testosterone, have been used by athletes in various sports. Among professional baseball players, Mark McGwire recently acknowledged using them off and on for nearly a decade, including 1998, when he hit 73 home runs to set a new major league single-season record. New York Yankees third baseman Alex Rodriguez has acknowledged using the drugs, and allegations have linked other big-name players, including Barry Bonds and Roger Clemens, with their use.
For the study, Baggish and his colleagues at Harvard Medical School and McLean Hospital enlisted 19 male weight lifters, including 12 who reported taking, on average, about 675 milligrams of steroids a week for nine years and nine who said they never used steroids. The researchers used Doppler echocardiography, which uses ultrasound to generate moving pictures of the heart's size and function, to study the function of the each weight lifter's left ventricle, which is the blood-pumping chamber.
"The common myth is that steroids make the heart grow massively large," Baggish said. "We didn't see that."
What they did see was that the hearts of the steroid users did not contract as vigorously and relax as efficiently as those of the nonusers.
The ejection fraction of the steroids users -- which is the volume of blood expelled with each beat -- was below normal in 10 of the users but only one of the nonusers. A healthy left ventricle has an ejection fraction of 55 to 70 percent but only two steroid users met that standard, the study found. Also, the measure of relaxation efficiency, which reflects the rate at which blood refills the left ventricle, was reduced by almost half in the steroid users.
"The number of persons in the study was small, and this needs to be studied in larger trials, but the data from this pilot study suggest that steroid use predisposes people to heart failure," Baggish said.
Heart failure, progressive loss of the ability to pump blood, is a leading cause of cardiac deaths.
However, it's not clear from the study how long steroids must be used to cause such heart damage, Baggish said. "Several small studies of shorter duration find damage only with heart relaxation, not contraction," he said. "As use continues, toxicity develops."
And he noted that there have been, "numerous case reports of horrific vascular events from short-term use."
Baggish said he hopes to repeat the study with a larger group of participants to confirm the findings. Meanwhile, he said, "when you add up all of the organ systems that steroids do damage to, and the heart is just one important organ, the logical recommendation is that steroid use is a no-no, for cosmetic or athletic purposes."
The U.S. National Institute on Drug Abuse has more on the dangers of steroids.
Calcium Scan Improves Heart Risk Prediction
TUESDAY, April 27 (HealthDay News) -- Adding a computed tomography test to measure calcium in coronary arteries improves predictions of future heart disease, a new study finds, but no one knows yet whether it's worth the cost and risk due to radiation exposure.
"This kind of evidence gives encouragement to go on and do additional testing, but it shouldn't convince us that this test should be done routinely," said Dr. Philip Greenland, a professor of preventive medicine at Northwestern University Feinberg School of Medicine, and a member of the team reporting the study in the April 28 issue of the Journal of the American Medical Association.
Computed tomography uses X-rays to get a detailed picture of heart structure. Its use in diagnosing existing heart disease has become controversial because X-ray exposure increases the risk of cancer. The new study of nearly 6,000 healthy Americans was done to see whether the technique could improve the predictive power of existing cardiac risk factors such as high blood pressure, high cholesterol and obesity.
The study began in July 2000 and ran through May 2008. It used two models to predict the five-year risk of a heart attack, resuscitated cardiac arrest or death from coronary heart disease: the traditional risk factors; or those risk factors plus the coronary artery calcium score.
At 5.8 years, the participants had experienced 209 coronary heart disease problems and 122 "major events" -- that is, heart attacks, deaths from coronary heart disease, or cardiac arrest followed by a resuscitation.
The second model, which used the regular risk factors plus the calcium scan, was able to predict an additional 23 percent of the participants who would go on to experience a harmful cardiovascular event. In addition, 13 percent the model reclassified as low-risk did not experience an adverse event.
But does that added predictive power make a difference in terms of saving lives and reducing unnecessary treatment?
"We didn't look at that," Greenland said. "What we can say here is that additional testing looks like it improves prediction. Whether it improves clinical outcome requires a different kind of study."
The first steps toward such a study have been taken. "We are in discussions with the National Heart, Lung, and Blood Institute and have been encouraged to submit a proposal," Greenland said.
Such a study might involve tens of thousands of participants and cost over $100 million, said Dr. Andrew J. Einstein, director of cardiac computed tomography research at Columbia University Medical Center in New York City.
The study would aim at determining whether more intensive treatment of traditional risk factors would improve survival of people classified as high-risk by the coronary artery calcium score. "No study has compared patients who had intensive preventive therapy with those who didn't and see if it makes a difference in terms of the number of heart attacks people have," Einstein said. "That study would be the ideal."
Such a trial needn't be as expensive as Einstein estimates, Greenland said. He puts the cost at "between $29 million and $50 million" and notes that the U.S. Institute of Medicine lists that kind of trial among the top 100 that should be done using funds provided for comparative effectiveness research in the newly approved health care program.
Cancer risk and cost are also parts of the equation. A well-controlled computed tomography scan gives about twice the radiation exposure as a mammogram, Greenland said. A new large-scale trial could show whether the added risk is justified by the number of lives saved, and the same is true of the cost, estimated to run between $200 and $600 per scan.
"Concern about radiation for any individual is minimal, and the cancer issue is 20 years down the line," said Dr. Joseph Ladapo, a clinical fellow in medicine at Harvard Medical School and Beth Israel Deaconess Medical Center in Boston. Incidental findings of a scan, such as possible lung problems, can also help justify its widespread use, Ladapo said.
But the time for widespread use has not arrived, Greenland noted. The new study results "are not an endorsement for screening," he said.
The why and how of a coronary calcium scan is described by the U.S. National Heart, Lung, and Blood Institute.
Nearly Half of U.S. Adults Have Heart Risk Factors
MONDAY, April 26 (HealthDay News) -- Nearly half of all American adults have either high blood pressure, high cholesterol or diabetes, each a major risk factor for heart disease, stroke and other cardiovascular problems, a new government survey finds.
The latest report on the U.S. National Health and Nutrition Examination Survey (NHANES) 1999-2006 shows that 45 percent of those questioned in the survey had at least one of the three risk factors: 30.5 percent with high blood pressure, 26 percent with high blood cholesterol levels and 9.9 percent with diabetes.
About one in eight adults -- 13 percent -- had two of the conditions and 3 percent had all three, the survey found. These rates were consistently higher among blacks.
What's even more alarming is that "15 percent of the population is unaware that they have one or more of these conditions," said survey author Cheryl D. Fryar, a health statistician with the U.S. Centers for Disease Control and Prevention.
That report is the latest in a nonstop pulse-taking effort by the CDC, which has adults answer a questionnaire about their health status and then performs physical examinations and blood tests.
The latest NHANES results were not particularly surprising, Fryar said. While the new report doesn't give trends over time, other work shows that blood cholesterol levels actually have dropped slightly because of the introduction of cholesterol-lowering drugs such as statins, she noted.
"For hypertension [high blood pressure], there has been no significant change from 1999 to 2006, and the prevalence of diabetes has increased slightly," Fryar said.
Blacks had a particularly high incidence of hypertension, 42.5 percent, compared to 29.1 percent of non-Hispanic whites and 26.1 percent of Mexican-Americans. High blood cholesterol was more common among non-Hispanic whites (26.9 percent) than among blacks (21.5 percent) and Mexican-Americans (21.8 percent), while diabetes was more common among blacks (14.6 percent) and Mexican-Americans (15.3 percent) than among non-Hispanic whites (8.3 percent), according to the report.
The percentage of people who had one or more risk factors and were unaware of it was consistent across the three ethnic categories, the survey found.
The CDC survey doesn't attempt to learn the reason why the incidence of these major risk factors is so high, Fryar said.
Dr. Clyde W. Yancy, medical director of the Baylor Heart and Vascular Institute at Baylor University Medical Center, and president of the American Heart Association, thinks he knows the reason: obesity.
"The burden of risk is directly related to the burden of obesity," Yancy said. "Obesity is directly related to high blood pressure, directly related to diabetes, directly related to an abnormal lipid profile."
And with 60 percent of adult Americans and 30 percent of younger Americans overweight or obese, the burden threatens to become worse, he said.
While the message about obesity and what causes it -- lack of exercise, poor diet, overeating -- is sent repeatedly, "people don't get it," Yancy said. "They are putting us at the risk of having a generation of Americans that has worse health than the previous generation, which has never happened before," he said.
The CDC report is "a call to arms," Yancy said. "Targeting obesity should now be on the top of the radar screen for everybody."
Hypertension, high cholesterol and diabetes are among the cardiovascular risk factors listed by the American Heart Association.
Brown Rice Tied to Better Heart Health in Study
MONDAY, April 26 (HealthDay News) -- Two kinds of rice -- brown and half-milled rice -- may reduce the risk of heart disease and high blood pressure by interfering with a protein linked to those conditions, research suggests.
In a new study, researchers report that the findings could indicate that brown rice is better than white rice when it comes to protecting the body from high blood pressure and artherosclerosis (hardening of the arteries).
"Our research suggests that there is a potential ingredient in rice that may be a good starting point for looking into preventive medicine for cardiovascular diseases," said researcher Satoru Eguchi, an associate professor of physiology at Temple University School of Medicine in Philadelphia.
Eguchi and colleagues said their experiments show that an ingredient in brown rice appears to combat a protein known as angiotensin II that contributes to high blood pressure and clogged arteries.
The ingredient is in a layer of rice that is stripped away when brown rice is converted to white rice. But the layer can be preserved in half-milled (Haigamai) and incompletely milled (Kinmemai) rice, which are popular in Japan.
The study is slated to be released at the Experimental Biology annual conference, April 24-28, in Anaheim, Calif.
The U.S. National Library of Medicine has details on nutrition.