A study published in the medical journal Pediatrics reported that boys treated with medication for attention-deficit/hyperactivity disorder (ADHD) had an 85 percent reduced risk of a substance abuse disorder 4 years later. Many parents and doctors have questioned whether stimulant drugs such as Ritalin that are used to treat ADHD in children could set the stage for substance abuse later in life. Their worries are based on the fact that these drugs can be addictive to teenagers and adults.

The researchers, funded by the National Institute on Drug Abuse (NIDA) and the National Institute of Mental Health (NIMH), drew their conclusions from boys over 15 years old. The scientists found that 75 percent of the boys with ADHD who were not medicated for the disorder later abused alcohol, marijuana, or other drugs. But only 25 percent of the medicated boys with ADHD had such problems at the 4 year follow-up, compared to 18 percent of a control group of boys without ADHD.

ADHD is a disorder characterized by inattention, hyperactivity, or impulsiveness. People who continuously have a hard time keeping their mind on one thing, who can’t sit still, or can’t discipline themselves to think before they act may be diagnosed as having ADHD. No one knows what causes the disorder. Mother’s use of drugs during pregnancy, exposure to lead, and genes may be possible factors. Counseling and medications like Ritalin or Dexedrine can help to control the symptoms.

Why would potentially addictive drugs help prevent future substance abuse? Stimulants help 9 out of 10 children to focus and be more successful at school, home, and play. Avoiding negative experiences early in life may help to prevent addictions and other emotional problems later.

For more information on this research, call NIDA at 301-443-6245 or visit <http://www.nida.nih.gov/>. For more information on ADHD, call NIMH at 301-443-4513 or visit <http://www.nimh.nih.gov/publicat/adhdmenu.cfm>—a report from the NIH Word on Health, October 1999.

A new report from the National Institute of Environmental Health Sciences (NIEHS) concludes that the evidence for health risks from electric and magnetic fields (EMFs) is “weak”. Attention was first called to the health effects of using electricity in the late 1970’s when a study reported an association between childhood cancer mortality and the proximity of homes to power distribution lines. Fear has grown ever since that the weak EMFs produced by the generation, transmission, and use of electrical energy may cause cancer, reproductive problems or other illnesses.

The report does caution that EMF exposure “cannot be recognized as entirely safe”. There is “a fairly consistent pattern of a small increased risk with increasing exposure” for two diseases: childhood leukemia and chronic lymphocytic leukemia in adults such as electric utility workers who have occupational exposure to EMFs.

Still, the magnitude of the increased risk was found to be weak. The report says, “some other factor or common source of error could explain these findings.” Homes near power lines tend to be older, closer together, and situated near busy streets. Some pollutant, for example, may be responsible for the higher rates of childhood leukemia.

No mechanism for how EMFs might cause human disease is currently recognized. Exposure to external electric and magnetic fields induces current in the body. But the current produced in the body by, say, an appliance’s magnetic field would typically be 1,000 times less than the currents produced on the surface of the body by the body’s own nerve impulses. Adverse effects on cells in a laboratory can only be induced by EMFs 1,000 to 100,000 times stronger than typical residential EMF fields.

Nevertheless, the report says that the evidence of health risks, while weak, is still sufficient to warrant concern. It urges the National Institute for Occupational Safety and Health and the Occupational Safety and Health Administration to review the report’s findings and evaluate if current occupational exposure standards are adequate. In the home, many electric utility companies can measure EMFs and identify sources of high fields, often caused by improper wiring. The report also urges manufacturers of household and office appliances to consider low cost measures to reduce magnetic fields from their products.

For printed copies of the report, contact NIEHS by phone: 919-541-7534, fax: 919-541-0144 or e-mail: emf-rapid@niehs.nih.gov. The report can also be found at <http://www.niehs.nih.gov/emfrapid/>. The EMF “Infoline” number is 1-800-363-2383.—a report from the NIH Word on Health, October 1999.

Fatal degenerative brain conditions that include “mad cow disease”, scrapie in sheep and goats, and Creutzfeldt-Jakob disease and kuru in humans are associated with abnormally folded proteins called prions. Infected brains look like sponges upon death. Scientists have had little clue how to combat prions before, but now researchers have honed in on a peptide–a piece of the prion itself–that inhibits the prion from converting into its more damaging form.

Scientists from the National Institute of Allergy and Infectious Diseases (NIAID) and their colleagues in Europe report in the Journal of Virology that the peptide blocked both mouse and hamster prion proteins from misfolding into their damaging forms, and also inhibited the conversion in scrapie-infected mouse cells. Scientists hope that the approach of inhibiting prion misfolding will be useful in combating these diseases–called transmissible spongiform encephalopathies (TSEs)–in a broad range of different species, including humans.

For more information on this finding, call NIAID at 301-496-5717 or visit <http://www.niaid.nih.gov/newsroom/prion.htm>.

For more information on Creutzfeldt-Jakob disease, call the National Institute of Neurological Disorders and Stroke (NINDS) at 301-496-5751 or visit <http://www.ninds.nih.gov/patients/disorder/creutjab/cjd.htm>.—a report from the NIH Word on Health, October 1999.

People who carry mutations of the BRCA2 gene are known to have higher risks of breast and ovarian cancers. Now, a report by scientists partially supported by the National Cancer Institute (NCI) published in the Journal of the National Cancer Institute also associates BRCA2 mutations with increased risks of several other cancers: prostate cancer, pancreatic cancer, gallbladder cancer, bile duct cancer, stomach cancer and malignant melanoma.

The genes BRCA1 and BRCA2 are especially important in suppressing the uncontrolled cell multiplication that results in cancer tumors. Mutations in these genes can frustrate their tumor suppressing abilities. Since BRCA2 was identified in 1995, more than 100 distinct disease-causing mutations in the gene have been found. These mutations may be inherited or can arise spontaneously. Some of the mutations may be detected with genetic tests, but genetic testing has advantages and disadvantages that must be carefully considered. For more information on these topics, call the NCI’s Cancer Information Service at 1-800-4-CANCER or visit <http://www.nci.nih.gov/>.—a report from the NIH Word on Health, October 1999.

For more information on Research Capsules, contact:
Harrison Wein, Ph.D.
Writer and Editor, NIH
Phone: 301-435-7489
Fax: 301-402-1485
E-Mail: weinh@od.nih.gov