Drug Used to Fight One Type of Cancer Linked to Risk of Another
A new study suggests that long-term use of tamoxifen to prevent breast cancer may increase the risk of developing endometrial cancer.
Researchers are aware that tamoxifen, an effective treatment for breast cancer thought to be useful in prevention, can also increase the risk of endometrial cancer. But scientists had believed the endometrial cancer associated with tamoxifen use to be a less malignant, more readily curable form. For that reason, they viewed the risk of not using tamoxifen as greater than the risk of using it.
But the new study by Dr. Flora van Leeuwen and her colleagues at the Netherlands Cancer Institute in Amsterdam questions that belief. The Dutch researchers studied 309 women who had suffered breast cancer followed by endometrial cancer, and another 860 similar women (controls) who had suffered only breast cancer. They obtained information about tamoxifen use and other risk factors for endometrial cancer, and analyzed tissue samples to determine the nature of the endometrial tumors.
They reported in the Sept. 9 Lancet (https://www.thelancet.com) that tamoxifen had been used by 36% of the endometrial cancer patients, but only 28.5% of the controls. The risk of endometrial cancer rose the longer that tamoxifen was used, they found. Women who used it for two to five years had double the normal risk of developing endometrial cancer, while those using it for five years or longer had seven times the normal risk. Advanced--and more deadly--tumors appeared in women who had used the drug for longer periods.
Even with these new findings, the benefits of tamoxifen for breast cancer patients far outweigh any risks, they concluded. But the results should give pause to physicians considering prescribing it as a preventive measure, they cautioned.
Longtime Joggers Keep Death on the Run
Long-term jogging significantly reduces the risk of death from cardiovascular disease, according to a new Danish study. Dr. Peter Schnohr and his colleagues at University Hospital in Copenhagen studied 4,658 men age 20 to 79 who did not suffer from cardiovascular disease. They were examined from 1976 to 1978, and again five years later. They were monitored until the end of 1988.
The team reported in the Sept. 9 British Medical Journal (https://www.bmj.com) that, controlling for other risk factors, the men who reported being joggers at both examinations had only 37% the risk of dying as those who did not jog or who jogged at only one of the examinations.
Prednisone Tests Well for Children’s Asthma
Children with a sudden, severe asthma attack respond better to an oral dose of the steroid prednisone than they do to the inhaled drug fluticasone, according to Canadian doctors. They recommended prednisone for asthmatic children in the emergency room.
Dr. Gerard Canny and his colleagues at the Hospital for Sick Children in Toronto studied 100 children age 5 and older who came to the hospital’s emergency room with a severe asthma attack. All received conventional bronchodilator therapy. Half also received oral prednisone and half received fluticasone, which is sold under the brand name Flovent.
They reported in the Sept. 7 New England Journal of Medicine (https://www.nejm.com) that 27% of those receiving prednisone had an excellent response to the drug, nearly three times as many as responded to fluticasone. None of the prednisone patients experienced a worsening of their breathing problems, but 25% of the fluticasone patients did. And finally, 31% of those receiving fluticasone had to be hospitalized, compared with only 10% of those receiving prednisone.
The team speculated that the inhaled drug was less effective in this study because mucus in the airways might prevent it from being efficiently absorbed. And they cautioned that the results might be different for children suffering less severe attacks.
Parkinson’s Can Affect the Heart, Study Says
Parkinson’s disease affects the heart as well as the brain, according to government researchers, a finding that suggests the disease may affect the entire nervous system. Neurologists have long known that Parkinson’s is associated with the death of specific types of cells in the brain, but a new study is the first to show the death of related nerve cells in the heart.
Dr. David S. Goldstein and his colleagues at the National Institute of Neurological Diseases and Stroke used a specialized imaging technique called positron emission tomography to examine the activity of nerve cells in the heart that control its beat rate. All 29 Parkinson’s patients, they report in the Sept. 5 Annals of Internal Medicine (https://www.annals.org/issues/current/toc.html), had decreased numbers of nerve cells that produce the stimulant norepinephrine. It did not matter whether the patients had taken drugs to control their disease, indicating that the cell loss was associated with the disease itself.
The findings, they said, may explain why many Parkinson’s patients suffer dizziness associated with hypotension (low blood pressure) when they stand up suddenly.
Cholesterol Type Linked to Heart Disease Risk
An obscure form of cholesterol in the bloodstream has been linked to heart disease, but researchers do not yet have good tests to measure its concentration routinely or drugs to reduce its concentration. The cholesterol is called lipoprotein a [Lp(a)], and high levels in the blood are associated with a 70% increase in heart attack risk, according to British researchers.
Epidemiologist John Danesh and his associates at Oxford University combined the results from 27 small studies of Lp(a) that included more than 5,200 individuals who had heart disease or who had survived a heart attack. They reported in the Sept. 4 Circulation: Journal of the American Heart Assn. (https://www.amhrt.org) that people with the highest Lp(a) levels had a 70% higher risk of heart attack over the 10 years of the study.
Lp(a) consists of two components: a molecule of low-density lipoprotein, the so-called bad cholesterol, and a large protein resembling plasminogen, which aids the blood’s natural clot-preventing activity. Scientists do not yet know its normal function or how it increases heart attack risk.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.
