Young blood

Red-cell rescue Blood transfusions could save the lives of thousands of elderly heart-attack patients each year. A Yale University study found that new blood could lower the risk of death for even mild heart-attack victims by one-quarter during the first month of recovery. Anemia is common among older patients. Doctors often check for it by measuring the percentage of oxygen-carrying red cells in the blood. Yet there is no consensus among doctors about treatment. The Yale researchers concluded that one in 10 heart-attack patients should be given transfusions if red cells make up less than a third of their total blood. Currently, they are only given to the most severe cases. "This is the first study to highlight the important link between anemia, blood transfusion, and mortality among elderly patients hospitalized for a heart attack," said principal investigator Harlan M. Krumholz of Yale School of Medicine. The study, which was published in the New England Journal of Medicine and covered Medicare patients treated for heart attacks in 1994 and 1995, also warned against giving needless transfusions. It said transfusions may hurt patients with red-cell levels over 36 percent. An editorial in the Journal by Lawrence Goodnough and Richard Bach of Washington University concluded that a "substantial number of lives may be saved" by transfusion. Healthy people can usually tolerate anemia with few problems. During a heart attack, however, the heart loses oxygen-and doctors say having oxygen-poor blood makes the situation worse. Not "high," but risky "High-normal" blood pressure may be more high than normal. Two new studies say that millions of people who are considered "high-normal" and who score below the official threshold for hypertension are still at risk of heart attacks and strokes. About 13 percent of adults in the United States have high blood pressure, and 19 percent have high-normal blood pressure, according to Ramachandran S. Vasan of Boston University School of Medicine. He and other researchers found that those in the "high-normal" category are two to three times more likely than those with normal blood pressure to suffer a heart attack, stroke, or heart failure in 10 years. The other study, by Duke University researchers, found that a healthier lifestyle can reduce the chance that stress-related high blood pressure will lead to a heart attack or stroke. The six-month study looked at 112 overweight or obese men and women with an average age of 48 and blood pressure that was either high or high-normal. Researchers divided them into three groups. They gave one group an exercise regimen, another a diet-and-exercise regime. The control group received no instructions. The exercise-and-diet group had lower blood-pressure readings during high emotional stress, while the exercisers had more modest improvements. "If you think you are lowering your blood pressure by exercise, it's not going to be all that much," said the study's senior author, James A. Blumenthal. "Combining exercise with dietary changes is where you are going to see the change in daily life and under stress." Memory scans High-tech brain scans may help doctors determine whether patients with mild memory lapses have early signs of Alzheimer's disease. Research reported in the Journal of the American Medical Association found such scans accurate in 93 percent of cases. The report comes as fears increase that the number of Alzheimer's cases will skyrocket as baby boomers age. The Alzheimer's Association predicts that over 14 million people in that demographic group will have the disease by mid-century. That compares to the 4 million estimated to have it today. Alzheimer's victims live an average of eight years after the onset of the disease, according to the group, but some people live for 20 years or more. The study of 284 patients in the United States, Belgium, and Germany found great success for positron emission tomography, or PET scans, said Daniel Silverman of UCLA. Doctors analyze the scans' images, looking for blue or violet splotches in the back of the brain. These indicate low glucose levels in the areas where the processing of language and memories takes place. Since glucose is the main fuel for brain cells, Alzheimer's is suspected when such results appear. Some doctors are unenthusiastic about using PET scans. "I suspect that this single paper will not convert the whole Alzheimer's community," said Bill Thies, vice president of medical and scientific affairs at the Alzheimer's Association.