 | What Your Doctor Is Reading | | |
Update From the Medical Journals: September 2009
September 30, 2009  By Mary Pickett, M.D.
Harvard Medical School What's the latest news in the medical journals this month? Find out what your doctor is reading. New Tests Diagnose Heart Attack More Quickly It can take 6 to 12 hours before doctors are certain whether a heart attack is occurring when it is not obvious from an electrocardiogram (EKG). If emergency department doctors could diagnose heart attacks faster, people could get treatment sooner — or be sent home if they didn't have a heart attack. Today, doctors most often rely on a blood test that looks for a protein called troponin. The sudden release of troponin into the bloodstream signals damage to the heart muscle. The August 27 issue of the New England Journal of Medicine describes the promising results from studies of four new blood tests — a new generation of "troponin" blood tests — that can identify heart attacks within three hours of their start. Two of the tests are approved for use in the United States. Researchers tested them on a total of 2,536 people who came into the emergency department with chest pains resembling a heart attack. The two tests were 94% to 96% accurate at predicting who did and who did not have a heart attack. Each test was checked against the blood tests that are commonly used now to verify a heart attack. This new, faster blood test for troponin will likely be in use soon in American hospitals. Troponin tests are an important tool, but they can't tell the whole story of a heart attack. Doctors will continue to use the patient's medical history, examination and EKG results as well to evaluate a heart attack victim. Back to top New Tests Diagnose Heart Attack More Quickly On September 10 we had some good news about H1N1 or so-called "swine" flu vaccine. A study published in the New England Journal of Medicine showed that after one dose — not two — the H1N1 shot protected against H1N1 flu. The 240 adults studied seemed to have a robust immune system response against the H1N1 flu within 8 to 10 days of getting the shot. In separate studies, researchers also showed that children older than 10 years could get adequate protection with one dose of vaccine. However, only about a third of children between the ages of 3 and 9 responded to the vaccine; this group might require a booster shot. Flu vaccine in a nose spray is also becoming available. The Centers for Disease Control and Prevention recommend that the following groups of people should get the new vaccine when it is available: - Pregnant women
- People who live with or care closely for one or more infants younger than 6 months
- Health care and emergency medical workers
- Everyone from 6 months through 24 years of age
- People ages 25 through 64 who have a chronic medical illness, such as an illness that suppresses the immune system, diabetes or lung disease
Back to top More News in Brief - Even a Small Amount of Smoking Provokes Heart Attacks. Twenty-three percent of adult Americans and 18% of youths smoke. These statistics include "light smokers." But is there any safe number of cigarettes you can light up in a day? On August 31, the journal Circulation: Journal of the American Heart Association released a study online. Researchers divided up smokers based on the number of cigarettes they smoked per day. Then they looked at the number of deaths from heart disease over 20 years for different levels of smoking. They collected health information from more than one million adults. Compared with non-smokers, people who smoked three or fewer cigarettes a day had more than one and one-half times the risk of death from heart disease — or a 64% increase in risk. People who smoked a half pack daily (8 to 12 cigarettes) had a 79% increased risk of death compared with non-smokers. Those who smoked a full pack per day doubled their risk for death — a 100% increase. People who were chronically exposed to high pollution or to second-hand smoke had a 20% to 30% higher risk than people who were not exposed. "Light" smoking is clearly a major risk factor for heart disease and death.
- Estrogen Now Blamed for Also Speeding Progression of Lung Cancer. Estrogen use after menopause has been associated with numerous health problems — cardiovascular disease, blood clots in the legs or the lungs, dementia, gallstone disease and breast cancer. The journal Lancet released an informative study on September 23 that linked estrogen use after menopause to yet another health problem — death from lung cancer. The study followed almost 17,000 women. The women were randomly assigned to take either estrogen plus progesterone or a placebo pill. After eight years of observing these women, researchers counted 73 deaths in the group receiving estrogen and progesterone, and only 40 in the group that took the placebo pill, despite roughly equal sizes of the two groups. Most of the extra deaths were from non-small-cell lung cancer. Experts are wondering if the estrogen stimulates some lung cancer cells to grow in a similar way to how it can stimulate cancer growth in the breast. Women who smoke should be aware of this special risk from post-menopausal estrogen treatment.
Back to top Mary Pickett, M.D. is an Associate professor at Oregon Health & Science University where she is a primary care doctor for adults. She supervises and educates residents in the field of Internal Medicine, for outpatient and hospital care. She is a Lecturer for Harvard Medical School and a Senior Medical Editor for Harvard Health Publications.
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