Am Fam Physician. 1999;59(6):1690-1697
Report on Treatment of Prostate Cancer
A technology assessment report from the Agency for Health Care Policy and Research (AHCPR) concludes that several testosterone-suppressing drugs used in the treatment of advanced prostate cancer have similar outcomes. The drugs, known as luteinizing hormone-releasing hormone (LHRH) agonists, produce similar survival rates and have roughly the same side effects. According to the AHCPR, costs of the LHRH agonists vary substantially.
The study was conducted by the Blue Cross and Blue Shield Association Technology Evaluation Center, an AHCPR evidence-based practice center. The three key issues addressed in the report are (1) the relative effectiveness of the methods available for monotherapy (orchiectomy, LHRH agonists and antiandrogens), (2) the effectiveness of combined androgen blockade compared with monotherapy and (3) the effectiveness of early compared with deferred androgen suppression treatment. The AHCPR believes that because of the trend toward earlier diagnosis of prostate cancer, it is important to understand the relative effectiveness and cost-effectiveness of alternative treatment strategies. Currently, approximately 185,000 new cases of prostate cancer, the second leading cause of cancer deaths in American men, are diagnosed annually.
The report found that combined androgen blockade, a more aggressive form of therapy, only marginally increases survival rates and causes more severe side effects. Evidence does not support the belief that certain subpopulations of patients who have a good prognosis may benefit from more aggressive treatment. There is also insufficient evidence to determine whether survival is improved by initiating therapy as soon as prostate cancer is detected.
A summary of “Relative Effectiveness and Cost-Effectiveness of Methods of Androgen Suppression in the Treatment of Advanced Prostatic Cancer” (AHCPR 99-EO11) is available on the AHCPR Web site at http://www.ahcpr.gov. Copies are available free of charge from the AHCPR Publications Clearinghouse, P.O. Box 8547, Silver Spring, MD 20907; telephone: 800-358-9295.
Pain Relief for Osteoarthritis of the Knee
The U.S. Food and Drug Administration has approved hylan G-F 20 (Synvisc) for the treatment of knee pain caused by osteoarthritis. Synvisc is a nonpharmacologic therapy derived from natural hyaluronan and was developed to have physical properties comparable with those of healthy synovial fluid. This new technology is called “viscosupplementation,” a procedure in which osteoarthritic synovial fluid is replaced and supplemented with Synvisc.
Synvisc is a sterile, viscous and elastic mixture of two new biopolymers—hylan A fluid and hylan B gel dissolved in saline. It is injected into the knee joint during a two-week period. A course of treatment is three injections given over 15 days.
In clinical trials, adverse reactions included mild to moderate transient local pain, swelling and effusion. Systemic adverse events were rare. The manufacturer emphasizes the need for strict adherence to aseptic technique during administration of Synvisc to minimize the risk for joint infection.
CDC Report on Physical Inactivity
Physical inactivity is prevalent throughout the United States, but particularly in rural areas, according to a report from the Centers for Disease Control and Prevention (CDC) published in the December 25, 1998, issue of Morbidity and Mortality Weekly Report. Overall, no leisure-time physical activity was reported in 28.7 percent of adults surveyed in 1992 and in 29.4 percent of those surveyed in 1994. Data for the report were taken from the 1996 Behavioral Risk Factor Surveillance System.
The prevalence of leisure-time physical inactivity was lowest (27.4 percent) in metropolitan areas (identified as having 1 million or more population) and highest (36.6 percent) in rural areas (less than 2,500 persons). Differences in physical activity between people living in metropolitan areas and those living in rural areas were greater for men (25.1 percent and 37.1 percent, respectively) than for women (29.5 percent and 36.2 percent, respectively). The overall prevalence of physical inactivity was lowest for respondents in the western United States (21.1 percent).
Because physical inactivity accounts for as many as 23 percent of all deaths from major chronic diseases, the CDC report recommends interventions to increase physical activity in all areas of the country and in all areas of the population to help decrease premature deaths.
Combination Product for Hepatitis C Treatment
The U.S. Food and Drug Administration (FDA) has approved another indication for Rebetron combination therapy. The combination therapy can now be used in patients with chronic hepatitis C who have not been treated with alpha interferon therapy. Previously, the product was approved only for use in patients who had relapsed following treatment with interferon alone. Rebetron is a combination of interferon alfa-2b recombinant for injection (Intron A) and ribavirin (Rebetol) capsules.
The FDA reports that clinical studies of treatment with the combination therapy over a course of 24 or 48 weeks resulted in higher virologic responses, compared with treatment with interferon alone. However, the same studies found that patients who had not responded to the combination therapy by week 24 were unlikely to benefit from further treatment.
The use of the combination therapy may cause serious adverse reactions, and the FDA emphasizes that the duration of the product's use be individually tailored to the patient's baseline characteristics, virologic response at week 24 and tolerability of the regimen. Female patients and female partners of male patients must not become pregnant while receiving this therapy and for six months after completing therapy.
Brochure Highlights Medications for Epilepsy
A brochure published by the Epilepsy Foundation provides information on 21 epilepsy medications, including seven new drugs and drug formulations that have been offered since 1993. The new medications featured in the brochure are lorazepam (Ativan), felbamate (Felbatol), tiagabine (Gabitril), lamotrigine (Lamictal), gabapentin (Neurontin), topiramate (Topamax) and diazepam rectal gel (Diastat).
The brochure explains how physicians select a specific medication for a patient, discusses side effects of medications and explains how generic medications are used. In addition, the effects of medication on pregnant women, children and the elderly are discussed.
Single copies of the brochure are available from the Epilepsy Foundation free of charge by calling 800-332-1000. Additional copies can be purchased by calling 800-213-5821. The Epilepsy Foundation Web site can be found at http://www.efa.org.
AAP Annual Report on Vital Statistics
An all-time low national infant mortality rate (7.1 deaths per 1,000 live births) and other continuing positive health trends for America's children are reported in the “Annual Summary of Vital Statistics,” published by the American Academy of Pediatrics (AAP) in the December 1998 issue of Pediatrics. Data in the report include the previous year's birth and mortality rates and fertility rates, as well as statistics on prenatal care, births to teenage mothers and single mothers, multiple birth weights and low birth weights. It also reports the leading causes of death for adults and for children in various age groups. In general, the trends reflected in the report are positive. The lead author of the report was Bernard Guyer, M.D., M.P.H., Johns Hopkins School of Public Health and Hygiene.
A higher percentage of pregnant women sought prenatal care during their first trimester in 1997 (82.5 percent) than in the previous year (81.9 percent). The number of infants with low birth weight was at the highest level reported since 1973, but this increase was largely accounted for by a significant increase in multiple births. The rate of multiple births in 1996 (the latest year that data were available) increased 5 percent over the rate in 1995.
The AAP notes that the data in the report should be used to focus on areas where further improvement is needed, for example, preventable injuries as a cause of death. The data on injury deaths in this year's report are presented to focus more closely on how the injury occurred, thus showing how the injury could have been prevented.
Cancer Facts and Figures
The American Cancer Society (ACS) has released its annual publication on cancer trends in the United States. “Cancer Facts & Figures 1999” includes the latest statistics on cancer incidence, mortality rates and survival rates, as well as information on specific cancers, cancer prevention and research.
An estimated 1,221,800 new cancer cases and 561,100 deaths are expected to occur in 1999. Lung cancer remains the number one cause of cancer-related deaths in the United States, with 158,900 deaths predicted for 1999, accounting for 28 percent of all cancer deaths. An estimated 171,600 new cases of lung cancer will be diagnosed in 1999. The incidence rate is declining significantly in men, from a high of 86.5 cases per 100,000 men in 1984 to 73.4 cases per 100,000 men in 1995. In the 1990s, the rate of increase among women began to slow. In 1995, the incidence rate in women was 42.6 cases per 100,000. Since 1987, more women have died each year of lung cancer than breast cancer, which, for over 40 years, was the major cause of cancer-related deaths in women.
An estimated 179,300 new cases of prostate cancer are expected this year, and an estimated 37,000 men are expected to die of the disease, the second leading cause of cancer death in men. Prostate cancer incidence rates remain higher in black men than in white men. Between 1989 and 1992, prostate cancer incidence rates increased dramatically, probably reflecting earlier diagnosis in men without any symptoms, through increased use of prostate-specific antigen (PSA) blood test screening. Subsequently, prostate cancer incidence rates declined, primarily among white men.
A special section in the report on colorectal cancer provides in-depth information on incidence and mortality, survival, risk factors, disease control strategies and treatment.
A companion piece titled “Cancer Risk Report: Prevention and Control 1998” is also available. This report presents data from the nation and the states on tobacco use, nutrition, physical activity and cancer screening. Utah had the lowest prevalence of current cigarette smoking among high school students in 1996 (15.9 percent), and Kentucky had the highest (31.7 percent).
The two reports are available on the ACS Web site at http://www.cancer.org. Copies of the reports may also be obtained by calling 800-ACS-2345.
New Vaccine Against Lyme Disease
The first vaccine against Lyme disease (Lymerix) has been approved by the U.S. Food and Drug Administration (FDA). The FDA approved the vaccine with caution, pointing out that the vaccine is not 100 percent effective and cannot be given to children. It is indicated for use in persons 15 to 70 years of age who live or work in grassy or wooded areas where ticks that may be infected with Borrelia burgdorferi live. Lyme disease is transmitted to persons through the bites of ticks infected with this bacterium.
Studies have shown that three injections of the vaccine over one year provide 78 percent protection against Lyme disease, while two injections provide only a 50 percent protection. The manufacturer recommends that the first two doses be given one month apart with the third dose given 12 months following the first dose. It is not known how long protection lasts. The FDA continues to recommend the use of preventive measures against infection, including wearing protective clothing, using tick repellent and removing attached ticks, even for persons who have had the vaccine.
The vaccine given in the trials was generally well tolerated. Local injection site reactions, including redness, soreness and swelling, were common. Influenza-like symptoms and muscle and joint pain occurred less frequently than other symptoms and were considered to be mild to moderate. Full prescribing information can be obtained by calling 888-LYMERIX, ext. 500. The Web site address for information on the vaccine is http://www.lymerix.com.