Am Fam Physician. 2000;62(4):885-887
ACSM Statement on Creatine Supplements
Interest in the effects of creatine use by a number of American athletes has led to numerous studies. Many of these studies have produced conflicting findings. The American College of Sports Medicine (ACSM) has published a consensus statement from their scientific roundtable titled “The Physiological and Health Effects of Oral Creatine Supplementation.” The statement appears in the March 2000 issue of Medicine & Science in Sports & Exercise.
The statement, which references hundreds of scientific studies, includes findings that show creatine use enhances exercise performance involving short periods of extremely powerful anaerobic activity and strength gains during strength training programs. According to the statement, the use of creatine does not enhance aerobic exercise performance or increase maximal isometric strength. The panel found that a dosage of 20 g per day is unnecessary; 3 g per day will achieve the same increase in phosphocreatine given time. Also, within the first few days, use of creatine can lead to weight gain, likely caused by water retention related to creatine uptake in the muscle. The panel found that changes in the muscle with the use of creatine do not mimic adaptive changes; therefore, creatine use cannot replace weight training.
The panel members agreed that there is no definitive evidence that creatine supplementation causes gastrointestinal, renal and/or muscle cramping complications. Creatine should not be used immediately before exercise, and should not be used by children or by women who are pregnant or lactating.
Monograph on Anxiety Disorders in Children
The Anxiety Disorders Association of America (ADAA) and the National Institute of Mental Health (NIMH) have published a new monograph on the treatment of anxiety disorders in children and adolescents. “Conference on Treating Anxiety Disorders in Youth: Current Problems and Future Solutions” was the result of a working conference held in October 1998 that was cosponsored by the ADAA and NIMH.
The monograph highlights the following areas for future research: improve diagnostic categories to better capture the clinical picture of anxiety disorders in children; expand the number and type of study designs for research on behavioral and pharmacologic treatments; refine measures of effectiveness of treatment to include behavioral observation, laboratory and performance-based measures; and conduct research on risk factors (such as family history, child's temperament, parenting behavior, and academic or social failure experiences) and on the existence and role of protective factors.
The text of the monograph is posted on the ADAA Web site at http://www.adaa.org. For more information, contact the ADAA by mail at 11900 Parklawn Dr., Ste. 100, Rockville, MD 20852-2624 or by calling 301-231-9350.
Use of Human Growth Hormone in Children
The Health Technology Advisory Committee (HTAC) has published a report on the use of recombinant human growth hormone (rhGH) in children with idiopathic short stature. HTAC was established in 1992 by the Minnesota state legislature. It is an independent, nonpartisan advisory body that evaluates new and emerging health care technologies based on existing scientific research and technology assessments.
According to the report, idiopathic short stature results when children are short, compared with others in their age group, for unknown or hereditary reasons. The use of rhGH to treat children with idiopathic short stature appears to have little risk of serious short-term harm, but long-term risks are not yet known. HTAC reports that the benefits of rhGH use in these children have not been determined. While therapy with rhGH appears to increase the growth rate of such children, its effect on final adult height is unclear. Also, it has not been decided whether final height or accelerated growth should be used to measure the success of treatment with rhGH.
HTAC makes the following recommendations for the use of growth hormone to treat idiopathic short stature in children:
The long-term safety, efficacy and cost-effectiveness of the use of rhGH to treat this condition should be established through additional studies.
RhGH should be used to treat idiopathic short stature only in controlled settings that generate safety and efficacy data.
Health care professionals should help parents and children address the problems that stem from idiopathic short stature.
This report (document 000201) and others published by HTAC may be obtained by calling 651-282-6374 or by e-mail (htac@health.state.mn.us/). There is no charge for the reports. All reports are also available on the HTAC Web site at http://www.health.state.mn.us/htac/index./htm.
Phenylketonuria in Pregnant Women
The Committee on Genetics of the American College of Obstetricians and Gynecologists (ACOG) has issued a committee opinion on maternal phenylketonuria. ACOG Committee Opinion No. 230 appears in the January 2000 issue of Obstetrics and Gynecology.
According to the ACOG committee, phenylketonuria is an autosomal recessive disorder of phenylalanine metabolism. If left untreated, the condition can cause severe mental retardation. The committee reports that routine screening for phenylketonuria in newborns and early dietary therapy with a phenylalanine-restricted diet have reduced mental retardation in affected persons. Because of these advances in detection and treatment of the disorder, large numbers of young adults with phenylketonuria who received early dietary treatment have IQs in the normal or near-normal range.
However, a new public health challenge has emerged from young women with phenylketonuria who fail to adhere to dietary restrictions. Metabolically normal fetuses of women with phenylketonuria who are on an unrestricted diet may develop mental retardation (92 percent risk), microcephaly (73 percent risk), heart defects (12 percent risk) and low birth weight caused by maternal hyperphenylalaninemia.
The ACOG committee states, “It has been suggested that dietary control should be implemented at least three months prior to conception to help prevent fetal structural defects, including cardiac defects.” If phenylalanine levels are normalized by eight weeks of gestation, evidence suggests that a reduction in intrauterine growth restriction will result.
The ACOG committee makes the following recommendations regarding women with phenylketonuria:
All women with phenylketonuria should be strongly encouraged to receive family planning and preconception counseling.
Women with phenylketonuria should restrict dietary phenylalanine before conception.
Ideally, pregnant women with phenylketonuria should be managed in consultation with physicians from experienced phenylketonuria centers.
Brochure on the Prevention of Falls in the Elderly
The National Center for Injury Prevention and Control (NCIPC) of the Centers for Disease Control and Prevention (CDC) has published a new brochure on the prevention of falls in the elderly. “What You Can Do to Prevent Falls” was designed specifically for older adults to provide tips on fall prevention.
The brochure outlines four main tips: (1) begin a regular exercise program; (2) make your home safer; (3) have your health care professional review your medicines; and (4) have your vision checked. According to the brochure, exercise is important in the prevention of falls because it can improve balance, strength and coordination. Because one half of all falls happen at home, the brochure suggests that older persons remove objects that can be tripped over, install handrails and lights in staircases and bathrooms, and wear supportive, non-slip shoes. The NCIPC encourages older persons to work with physicians and pharmacists to examine their medications to be sure that they will not make the patient drowsy or light-headed. Finally, the brochure stresses that poor vision can increase the chances of falling; therefore, older patients should be checked for glaucoma, cataracts and the correct vision prescription.
For more information, write to the NCIPC at Division of Unintentional Injury Prevention, 4770 Buford Hwy., NE, Mailstop K-63, Atlanta, GA 30341, or visit the NCIPC Web site (http://www.cdc.gov/ncipc).
U.S. Outbreak of West Nile Virus Infection
The Centers for Disease Control and Prevention (CDC) and the U.S. Department of Agriculture (USDA) have cosponsored a meeting of experts in a wide range of disciplines to review the U.S. outbreak of West Nile virus and to provide input and guidance on programs that should be developed to monitor virus activity. The guidelines appear in the January 21, 2000 issue of Morbidity and Mortality Weekly Report.
The emergence of West Nile virus in the northeastern United States in 1999 raised the issue of preparedness of public health agencies to handle sporadic and outbreak-associated vectorborne diseases. It is not known whether the virus can last through the winter, whether it has or will spread to new geographic locations, and what the implications of this disease will be. Because of these concerns, proactive laboratory-based surveillance and prevention and control programs should be established to limit the impact of the virus in the United States.
The guidelines cover the priority of enhanced surveillance in states that are already affected by the virus or that have the potential for being affected, the laboratory diagnosis of the virus, control of mosquitos to prevent transmission, public health infrastructure, interjurisdictional data sharing and research priorities.
NCI Pilot Project to Speed Cancer Research
The National Cancer Institute (NCI) is conducting a new pilot project, the Expanded Participation Project (EPP), that will speed cancer research by enabling more patients and physicians to participate in clinical studies that advance cancer care.
According to the NCI, Phase III clinical trials are the most reliable way to improve cancer treatment, but relatively few patients have the chance to participate in these studies. Traditionally, only physicians who are members of the NCI Cooperative Groups have had the opportunity to place patients in large-scale clinical trials.
The Cooperative Group system was established in 1955. It enrolls about 20,000 patients in NCI-supported multi-institutional clinical trials each year. Together, the 12 Groups receive more than $140 million in funding annually from the NCI, conduct hundreds of clinical trials among their component institutions at any given time and are the foundation of clinical cancer research in the United States.
The EPP complements the Cooperative Group system by allowing other qualified oncologists to have the same clinical trials privileges. The EPP offers these physicians a variety of important studies with simplified administration and direct reimbursement for the added time and effort involved in enrolling patients and collecting research data.
One major impediment to the Cooperative Group is that members can only enroll patients in studies supported by their own group. The EPP allows physicians to enroll patients in a wide range of NCI-sponsored Cooperative Group studies.
Sixteen clinical studies for the most common cancers—breast, lung, prostate and colorectal—are currently open to EPP physician members. More studies will be available later this year.
For more information, visit the EPP Web site at http://www.light.emmes.com/epp/. For more information on cancer, visit the NCI Web site at http://www.cancer.gov.