U.S. Food and Drug Administration
FDA Consumer magazine
September-October 2001
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A special review panel led by the National Institutes of Health has concluded after examining existing research that male latex condoms can effectively reduce transmission of HIV and gonorrhea. However, the panel's report also said that there isn't enough information from well-designed studies to determine how effective condoms are in preventing most other sexually transmitted diseases (STDs).
The report confirms that correct and consistent use of condoms can reduce the risk of HIV transmission. Epidemiological studies also indicate that condoms can prevent men from acquiring gonorrhea from a female partner, the report says. HIV is the virus that causes AIDS. The report, released on July 20, concluded that, because of limitations in study designs, epidemiological evidence currently is insufficient to "draw definite conclusions" about the effectiveness of condoms in preventing spread of chlamydial infection, syphilis, chancroid, trichomoniasis, genital herpes and human papillomavirus (HPV) infection.
The panel said that "the absence of definitive conclusions reflected inadequacies of the evidence available and should not be interpreted as proof of the adequacy or inadequacy of the condom to reduce the risk of STDs." The panel also recommended that more research be done.
The National Institutes of Health, the Centers for Disease Control and Prevention, the Food and Drug Administration, and the U.S. Agency for International Development organized a workshop in June 2000 to review the current research. Twenty-eight experts analyzed more than 138 peer-reviewed, published studies on the use of the male latex condom during penile-vaginal intercourse.
Analysis of combined data from several studies on related research questions showed an 85 percent decrease in risk of HIV transmission among consistent condom users versus non-users. These data provide compelling evidence that consistent use of the latex male condom is a highly effective method for preventing HIV transmission, the report said. Studies also show a 49 percent to100 percent reduction in risk of gonorrhea among men reporting condom use compared with non-users.
For HPV, the panel found there was no evidence that condom use reduced the risk of HPV infection, but study results suggested that condom use might afford some reduction in risk of HPV-associated diseases.
STDs, including HIV infection, affect more than 65 million people in the United States. Many STDs can cause infertility and problems with pregnancy, and can be passed from a mother to her infant. Long-term infection with HPV can cause cervical cancer if not diagnosed (through annual pap smears) and treated. In addition, most STDs increase the likelihood of transmitting HIV infection at least 2- to 5-fold. Most STDs can be treated successfully.
The workshop summary, "Scientific Evidence on Condom Effectiveness for Sexually Transmitted Disease (STD) Prevention," is available online at www.niaid.nih.gov/dmid/stds/condomreport.pdf.
Physicians have been advised against prescribing hormone replacement therapy (HRT) for the sole purpose of preventing heart attacks and strokes in women who already have cardiovascular disease. The recommendations were published in the July 24, 2001, issue of Circulation: Journal of the American Heart Association.
The new position is based on recent scientific studies about the role of HRT in reducing the risk of coronary heart disease in postmenopausal women. For postmenopausal women who have had a heart attack or stroke, the guidelines recommend that HRT not be initiated for secondary prevention. This recommendation is based, in part, on results of the Heart and Estrogen Replacement Study (HERS), a large-scale study that found no benefit of HRT among women with heart disease.
For preventing a first heart attack or stroke, the association recommends reducing risk factors such as high cholesterol and blood pressure through lifestyle changes and, if needed, with medications. Pending the results of ongoing studies, the guidelines recommend that the decision on HRT use be based primarily on non-heart related benefits and risks.
For women with diagnosed cardiovascular disease who are undergoing long-term hormone replacement therapy, the decision to continue or stop HRT should be based on established non-coronary benefits and risks, as well as patient preference.
Lori Mosca, M.D., Ph.D., lead author of the American Heart Association science advisory, titled "Hormone Replacement Therapy and Cardiovascular Disease," said that the established benefits of HRT for the treatment of menopausal symptoms, such as hot flashes and osteoporosis prevention, must be weighed against risks for blood clots, gallbladder disease, and a possible increased risk of breast cancer.
"The new guidelines recommend essentially taking HRT out of the risk-benefit equation for women who have already had a heart attack or stroke," Mosca said. "For postmenopausal women without heart disease, we do not suggest that HRT be taken completely out of the equation. We state that heart disease prevention should not be used as the sole purpose of therapy."
Cardiovascular diseases, which include heart attack and stroke, are the leading causes of death in women. After menopause, risk for these diseases rises sharply.
West Nile virus was recognized in the Western Hemisphere for the first time in 1999, when it caused an epidemic of encephalitis and meningitis in New York City. Intensive hospital-based, public health surveillance registered seven deaths in the region from meningoencephalitis (inflammation of the brain and spinal cord).
A detailed analysis of the New York City outbreak suggests that a substantial--and previously undiagnosed--number of West Nile fever cases accompanied the 59 cases of potentially deadly West Nile meningoencephalitis seen during the outbreak, researchers say.
West Nile virus was first isolated in the West Nile District of Uganda in 1937. According to the Centers for Disease Control and Prevention (CDC), most infections are mild with symptoms such as fever, headache, and body aches. People older than 50 are at highest risk of severe disease, which may result in a number of symptoms, including high fever, disorientation, muscle weakness, and, rarely, death.
The New York City Department of Health and the CDC conducted a household-based survey in October 1999, about six weeks after the outbreak in New York. Investigators used a representative sample of households in an area surrounding the center of the outbreak. Blood samples were taken and tested for antibodies specific for the West Nile virus.
The study, published in the July 28, 2001, issue of The Lancet, concluded that for every diagnosed case of meningoencephalitis, there were likely to be 140 other infections, including 30 individuals with an influenza-like illness.
Six hundred and seventy-seven individuals from 459 households took part in the survey. Nineteen (2.6 percent) were seropositive, which means they had the virus confirmed by blood test; about a third of these individuals (31 percent) reported a recent febrile illness, compared with 70 of 648 (11 percent) who were seronegative. A febrile syndrome with fatigue, headache, muscle pain, and painful joints was highly associated with the virus.
The investigators conservatively estimated that the New York outbreak consisted of about 8,200 (range 3,500-13,000) West Nile viral infections, including about 1,700 febrile infections. The risk of severe illness was higher among older people, with one case for every 50 infections in those aged 65 years and over, compared with one case for every 300 infections in people younger than 65.
Use of DEET-containing mosquito repellent was protective of infection in those who spent two or more hours outdoors between dusk and dawn, the peak biting period for West Nile virus-carrying Culex mosquitoes. But 70 percent of residents reported never using mosquito repellent even after the outbreak was recognized.
The CDC recommends eliminating standing water from around your home to avoid mosquito bites and reduce the risk of contracting West Nile virus.
Healthy men are being sought for the largest-ever prostate cancer prevention study. The National Cancer Institute (NCI) and the Southwest Oncology Group (SWOG) have launched the Selenium and Vitamin E Cancer Prevention Trial, known as SELECT. The goal of the research is to determine if selenium and vitamin E can protect against prostate cancer, the most common form of cancer in men after skin cancer. More than 400 sites in the United States, Puerto Rico, and Canada are recruiting participants for SELECT, which will include 32,400 men and take up to 12 years to complete.
It's the first study designed to look specifically at the effects of vitamin E and selenium, both separately and together, in preventing prostate cancer. Previous research on other kinds of cancer suggests these nutrients might prevent prostate cancer. Selenium and vitamin E, both naturally occurring nutrients, are antioxidants. They are capable of neutralizing toxins known as "free radicals" that might otherwise damage the genetic material of cells and possibly lead to cancer.
During 2001, prostate cancer will be diagnosed in about 198,100 Americans, and more than 31,500 men are expected to die of the disease. Risk factors for the disease include being older than 55, African American, or having a father or brother with prostate cancer.
According to the NCI, it is crucial for men of all races and ethnic backgrounds to participate in SELECT. African American men, who have the highest incidence of prostate cancer in the world, are especially encouraged to join the trial. Prostate cancer also strikes African Americans at a younger age, so they are eligible to enroll in the study at age 50 rather than the age 55 minimum set for men of other racial and ethnic backgrounds. There is no upper age limit for participation in SELECT. In addition, SELECT participants must have never had prostate cancer or any other cancer--except non-melanoma skin cancer--in the last five years, and must be in generally good health.
For more information on SELECT and participating centers, call the NCI's Cancer Information Service at 1-800-422-6237 (English and Spanish). Callers with TTY equipment may call 1-800-332-8615. When calling from Canada, contact the Canadian Cancer Society's Cancer Information Service at 1-888-939-3333 (English or French). Visit the NCI's Web site at http://cancer.gov/select/ or SWOG's Web site at http://swog.org and choose SELECT.
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2001-AUG-27.