By Ed EdelsonHealthDay Reporter
Friday, May 9, 2008; 12:00 AM
THURSDAY, May 8 That unusual, harsh sound a doctor can hear when passing a stethoscope over a main artery to the brain could indicate an increased risk of heart attack and death from heart disease and stroke, a new study finds.
The sound -- called a carotid bruit (pronounced brew-ee) -- is caused by turbulent blood flow due to buildup of fatty deposits in one of the two arteries that carry blood to the front and middle part of the brain. It is usually regarded as a possible indicator of increased risk of stroke.
Now an analysis of 22 studies finds that people with carotid bruits are more than twice as likely to have heart attacks or to die of cardiovascular disease. "The presence of a carotid bruit should heighten clinician concern for coronary heart disease," said the report by physicians at Walter Reed Army Medical Center in Washington, D.C.
The studies included 17,295 people who were followed for an average of four years. "In the four studies in which direct comparison of patients with and without bruits were possible, the odds ratio for myocardial infarction [heart attack] was 2.15 and for cardiovascular death 2.27," the report said.
The findings are published in the May 10 issue ofThe Lancet.
Using the presence of a bruit as an indicator of cardiovascular risk could be helpful, but "there are some unresolved questions about the usefulness of carotid bruit and prognosis," said Dr. Victor Aboyans, a cardiologist at Dupuytren University Hospital in Limoges, France, and co-author of an accompanying editorial in the journal.
"First, many of the patients who were studied already had cardiovascular disease, so what is the additional value of carotid bruit in such a case?" Aboyans asked. "The second issue is that some patients who don't have carotid bruit may have other evidence of cardiovascular disease."
Several studies have shown that starting preventive measures for stroke on the basis of screening for carotid bruit aren't useful, Aboyans said. Nevertheless, presence of carotid bruit could prompt physicians to be more aggressive in recommending measures to reduce the risk of cardiovascular disease, such as cholesterol reduction, he said.
Dr. Deepak Bhatt, associate director of the Cleveland Clinic Cardiovascular Coordinating Center, said, "The [study authors'] recommendation that they be even more aggressive with risk modification, that is good clinical judgment."
Physicians routinely listen for possible carotid bruits when doing a physical examination of people who are middle-aged or older, Bhatt noted.
Studies have shown that there's a link between the risk of stroke and of coronary heart disease, Bhatt said. "The core knowledge already exists," he said. "This study helps put a number on how high the risk is."
But the study raises some practical issues, Bhatt added. "One is whether, if a carotid bruit is found, to go ahead and do an ultrasound examination," he said. "I would say yes, but it is controversial. The U.S. Preventive Task Force recommends against routine ultrasound in general."
The term anemia means an insufficient supply of red blood cells and hemoglobin, the protein in red blood cells that transports oxygen to cells throughout the body. Anemia can develop when red cells and hemoglobin are lost through bleeding, when the body has trouble producing them, or when they are somehow destroyed.
Because their cells aren't getting enough oxygen, people with anemia may feel fatigued, listless, dizzy and confused.
In iron-deficiency anemia, the type of anemia most common in women, low iron levels are the problem. Iron plays a crucial role in the production of red blood cells and hemoglobin, so if it's not available in sufficient amounts, red cell production drops.
There is a difference between iron deficiency and iron-deficiency anemia, says Craig S. Kitchens, M.D., professor of medicine at the University of Florida in Gainesville. It's possible to be iron-deficient without being anemic, he says. A woman who is iron-deficient has just enough iron to get by, while a woman who is anemic doesn't have enough iron to meet her body's needs, he says.
Other, less common forms of the disease include anemia of chronic disease, in which anemia signals a serious condition such as liver disease, rheumatoid arthritis, inflammatory bowel disease or lupus, a chronic inflammatory disease that affects the skin, joints, kidneys, nervous system and mucous membranes; megaloblastic anemia, due to a deficiency of vitamin B12 or folic acid; pernicious anemia, in which there's difficulty absorbing vitamin B12; and aplastic anemia, in which the bone marrow has difficulty producing red blood cells. These types of anemia occur with about the same frequency in women and men.
Women and Iron
One reason women are more susceptible to iron-deficiency anemia is that, besides losing the one to two milligrams of iron that's normally expelled from the body every day, women lose an additional one milligram a day during menstruation.
Pregnant women may develop anemia for two reasons. First, while the number of red blood cells increases during pregnancy, the amount of fluid, or plasma, containing the cells goes up even more. The result is that the ratio of red blood cells to plasma changes. Second, if a woman is low in iron before she conceives, having the fetus draw on her low stores will push her into anemia, says Dr. Kitchens. Iron deficiency during pregnancy has been associated with complications such as low birthweight, premature birth, abnormalities of the fetus and even fetal death.
Women also can lose iron during childbirth, when as much as 250 to 300 milligrams of iron may be lost through bleeding.
Eating habits may make any woman prone to iron-deficiency anemia, says Dr. Kitchens. At the top of the list are eating too little and not eating meat. "If you are a woman who has or is bordering on bulimia or anorexia nervosa, you are at much more risk," he says. And "if you are vegetarian, you're at much, much more risk."
Vegetarians are at higher risk because heme iron, the type used most readily by the body, comes from meat. Another type of iron, nonheme iron, is found in certain vegetables and nonmeat products, but it's not absorbed as well by the body.