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 The Latest In . . . ALTERNATIVES TO ANIMAL TESTING Tests Don’t Prevent Drug Risks Although animal testing is required by law for all new drugs, it does not make them safe. An April 15, 1998, JAMA study shows how frighteningly common unexpected drug reactions are. In 1994, 2.2 million hospitalized patients had serious adverse reactions, including 106,000 fatalities, making pharmaceuticals one of the top causes of hospital deaths. These were not prescribing errors but rather were due to side effects of the drugs themselves. More Drugs Pulled from the Market Roche Laboratories pulled its drug Posicor off the market in June. The drug had been found to harm the liver’s ability to eliminate other drugs, allowing them to accumulate to dangerous levels in the body. Posicor was in use by 400,000 people for high blood pressure or angina. Given the plethora of antihypertensives already available, it is unclear why Posicor was approved at all. Exercise and vegetarian diets are also effective for both hypertension and angina. The popular new painkiller Duract was also discontinued in June after four users died and eight more needed liver transplants. This was bad news for drugmaker Wyeth-Ayerst, which also pulled weight-loss drugs Redux and Pondimin off the market in September 1997. New Drug Testing Software Replaces Some Animal Tests It is now possible to predict the results of some animal tests, based on past results with similar compounds. A combined effort of Multicase, Inc., the University of Pittsburgh, and the Food and Drug Administration has produced software that puts this new technology to work so that manufacturers can forego many such tests. The first programs predict which compounds cause birth defects and fertility problems. The new software entails a one-time cost of $56,000 to $100,000 but is far cheaper than the cost of even a single animal test, not to mention the benefits to animals and efficiency for manufacturers. Multicase, Inc., is a spin-off of Case Western Reserve University in Cleveland. Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in hospitalized patients. JAMA 1990;279:1200-5. HEART DISEASE Risk Begins in Childhood A study in the New England Journal of Medicine found that in autopsy studies of 204 children and young adults, aged 2 to 39, virtually all had fatty streaks in their aortas, a sign of early atherosclerotic changes. Half of those below age 15 and 85 percent of those 21 to 39 years had fatty streaks in their coronary arteries. The study found that the same risk factors that encourage heart disease in older folks—high cholesterol levels, overweight, high blood pressure, and smoking—do the same in the young. Berenson GS, Srinivasan SR, Bao W, et al. Association between multiple cardiovascular risk factors and atherosclerosis in children and young adults. N Engl J Med 1998;338:1650-6. CANCER More on Milk’s Cancer Link Premenopausal women with even small increases in blood levels of insulin-like growth factor I (IGF-I) have up to seven times the breast cancer risk of women with lower levels, according to a report in The Lancet. IGF-I is a potent stimulus for cancer cell growth. It is produced in the body and is also found in dairy products. It is especially concentrated in milk from cows treated with bovine growth hormone. IGF-I has also been linked to prostate cancer. Exercise Helps Recovery About 70 percent of people undergoing cancer treatment experience a debilitating loss of energy that can persist long after surgery, radiation, or chemotherapy. Reports in Cancer, May 1, 1997, and the Quarterly Journal of Strength and Conditioning Research, January-March 1998, show that both aerobic exercise and weight training can improve their energy levels and hemoglobin concentrations. Exercise also significantly reduces pain. When Tests Give False Results Women who have regular mammograms and breast exams are surprisingly likely to be told they have a test result suspicious of cancer when in fact they do not have cancer at all, according to a new report in the New England Journal of Medicine. Such false positive findings occur in about one-third of women during any given ten-year period. Hankinson SE, Willett WC, Colditz GA, et al. Circulating concentrations of
insulin-like growth factor-I and risk of breast cancer. Lancet 1998;351:1393-6. FOODBORNE ILLNESS Thank Your Meat-Eating Friends Salmonella bacteria are getting harder and harder to treat. A strain resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline infects between 68,000 and 340,000 people annually, according to the Centers for Disease Control and Prevention, and some strains are gaining resistance to the remaining antibiotics. Dr. M. Kathleen Glynn pointed out that resistance emerges on farms, where nearly half of the 50 million pounds of antibiotics produced each year in the U.S. are used, mainly as growth-promoters. Once resistance is developed it can be passed on to other bacteria. Salmonella bacteria are found in the feces of chickens and other animals and contaminate their flesh and any other products they touch. Food Poisonings Continue A two-year-old child died this summer from complications of E. coli O157:H7 poisoning, apparently contracted from another child who passed the illness along to over two dozen others who shared a chlorinated wading pool at Atlanta’s White Water Park. Several children became seriously ill, including the three-year-old son of Atlanta Braves shortstop Walt Weiss. The child who eventually died was a vegetarian, leading investigators to suspect the swimming pool rather than food sources. The pool hurriedly required all children to wear plastic sealed pants. Later investigation found that the pool bacteria genetically matched samples from beef recalled by Bauer Meat, a Florida meat processor which distributed hamburger in Georgia. The tragedy continued when the owner of the processing company committed suicide after the Department of Agriculture shut down his plant. This summer was a bad one for foodborne illness. A Maine woman died and at least 21 people became ill after eating E. coli O157:H7-contaminated hamburger later recalled by 124 New England stores. E.coli in cheese curds sickened 28 people—hospitalizing a dozen—in Wisconsin. A milder form of E. coli afflicted 4,500 people who ate tainted potato salad from a Chicago deli. And the Malt-O-Meal Company recalled more than 2 million pounds of toasted oat cereal after several consumers became ill from salmonella. E. coli and salmonella reside in the intestinal tracts of animals and are transmitted to meat-eaters, who may pass them to others through personal contact or contamination of foods, utensils, or kitchen surfaces. Silver Bullet Tarnished A spray designed to stop the spread of salmonella is no silver bullet, according to industry officials. PREEMPT was gushingly unveiled in March by Agriculture Secretary Dan Glickman, but Travis Cigainero, D.V.M., the corporate veterinarian for Pilgrim’s Pride, said, “There’s a media blitz, but there’s nothing behind it.” Similar products have been used since the 1950s with little success. “[They] have a bad track record over a 40-year period,” said Lester Crawford, former head of the Department of Agriculture’s food safety division. “It isn’t going to work long.” USDA Puts Sunny Side Up on Egg-Related Deaths The U.S. Department of Agriculture revealed that salmonella-tainted eggs sicken 661,000 people each year and kill 390. Believe it or not, that’s good news, says USDA. The Department had originally put the figure at 883,000 before taking another look at their count. Salmonella contamination is believed to occur in 2.3 million of 46.8 billion eggs produced each year. Glynn MK, Bopp C, Dewitt W, Dabney P, Mokhtar M, Angulo FJ. Emergence of multidrug-resistant salmonella enterica serotype typhimurium DT104 infections in the United States. N Engl J Med 1998;338:1333-8. NEW RESEARCH METHODS Researchers Probe Brain Abnormalities Human brain studies are helping to clarify the causes of autism and dementia. Using magnetic resonance imaging, Dr. Wendy Kates and her colleagues at the Johns Hopkins University in Baltimore compared a seven-year-old autistic boy with his twin brother. Certain parts of the brain were smaller in the autistic boy than in his twin, while other brain areas were smaller in both boys compared to children from other families. The results not only indicate the neurological basis for autism but also suggest that milder abnormalities may be found in the families of autistic children. A follow-up study is planned with ten twin pairs. In a second report, researchers at the University of Washington found a mutation in the tau gene on chromosome 17 in two families with a hereditary form of dementia. The mutation appears to lead to microscopic abnormalities, called neurofibrillary tangles, in the brain tissue. The same tangles are found in Alzheimer’s disease, leading the researchers to suggest a hunt for the same genetic factors in Alzheimer’s disease. Both reports were published in the June 1998 issue of the Annals of Neurology. |
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