head lice

Combing may outperform over-the -counter chemicals.

* THE QUESTION Mere mention of head lice can make parents of young children squirm and then sigh, aware of the effort it will take to get rid of the varmints. With the tiny insects showing increasing resistance to commonly used insecticides, might special combs be an effective alternative?

* THIS STUDY randomly assigned 133 children with lice to have their heads treated with an over-the-counter insecticide (malathion or permethrin, mixed with water) or to have a fine-toothed comb methodically pulled through their wet hair after conditioner had been applied. Combing was done four times in about two weeks. A single dose of the chemical mixture was used, as recommended by the manufacturer. After treatment, head lice had disappeared from 57 percent of the combing group and 13 percent of those treated with an insecticide.

* WHO MAY BE AFFECTED BY THESE FINDINGS? Anyone who comes in close contact with someone who has head lice because the tiny, wingless, parasitic insects are highly contagious. Children are affected most often, through child care, school, sports and even slumber parties. Head lice do not indicate uncleanliness or poor hygiene.

* CAVEATS Use of a different type comb may yield different results; those used in the study were from a British "Bug Buster" kit available via the Internet. The authors noted that a double dose of insecticide most likely would kill lice that emerged from eggs not killed by the first dose, but that is considered an unlicensed use of the chemical in England, where the study was conducted. Although four times more effective than insecticides, the two-week combing process still did not eliminate lice from 43 percent of its users.

* FIND THIS STUDY Aug. 5 online edition of BMJ; abstract available at www.bmj.com (click "Online first").

* LEARN MORE ABOUT head lice at www.kidshealth.org and www.cdc.gov.

osteoporosis

Sequential treatments appear to extend initial drugs' gains.

* THE QUESTION One way to treat the thinning and increasing fragility of bones from osteoporosis is with injections of parathyroid hormone, which stimulates new bone growth. Because this hormone can be taken for no more than two years, might subsequent treatment with a drug that slows bone loss help maintain the gains made?

* THIS STUDY randomly assigned 238 post-menopausal women with osteoporosis who had taken parathyroid hormone for one year to take either alendronate (Fosamax) or a placebo for an additional year. Participants also took calcium and vitamin D supplements daily. In the second year, the alendronate group recorded increases in bone density at the spine and hip (about 5 percent and 4 percent, respectively), whereas the placebo group recorded a 2 percent decrease at the spine and no change in the hip measurement. For the two-year period, the cumulative increase for spine density was 31 percent when parathyroid hormone was followed by alendronate vs. 14 percent when it was followed by a placebo.

* WHO MAY BE AFFECTED BY THESE FINDINGS? Post-menopausal women, about half of whom are likely to have an osteoporosis-related fracture at some point in their lives.

* CAVEATS The study did not assess the effect on fractures. Whether the findings apply to other drugs in the same class as alendronate (bisphosphonates) remains unclear. The study was funded in part by Merck, which also supplied the alendronate; NPS Pharmaceuticals provided the parathyroid hormone. Six of the nine main authors have received fees from these companies.

* FIND THIS STUDY Aug. 11 issue of the New England Journal of Medicine; abstract available online at www.nejm.org.

* LEARN MORE ABOUT osteoporosis at www.osteo.org and www.nih.gov/news/WordonHealth (click "Previous Issues," then "December 2003").

breast cancer

Switching from tamoxifen may help prevent relapses.

* THE QUESTION Tamoxifen has become a standard treatment for breast cancer in its early stages, prized for its ability to stem the recurrence of tumors. However, the risk of developing uterine or endometrial cancer and blood clots increases the longer it's used. Might switching to a similar drug after two years prove as effective without the complications?

* THIS STUDY analyzed data from two studies involving 3,224 women with breast cancer who had taken tamoxifen daily for two years. They were randomly assigned to continue tamoxifen or switch to anastrozole. Two years later, cancer had returned or spread in 40 percent fewer of the women who had changed drugs than those who had continued on tamoxifen (67 vs. 110). Bone pain, fractures and nausea were more common in the anastrozole group; blood clots were more common among those who took tamoxifen the whole time.

* WHO MAY BE AFFECTED BY THESE FINDINGS? Women with breast cancer who have been treated with tamoxifen. About one of every seven women can expect to develop breast cancer in their lifetime.

* CAVEATS Whether switching drugs after a different time period or switching to an aromatase inhibitor other than anastrozole would alter the results was not determined. The study was not long enough to reveal any differences in survival. AstraZeneca partially funded the study and provided the medications.

* FIND THIS STUDY Aug. 6 issue of The Lancet; abstract available online at www.thelancet.com.

* LEARN MORE ABOUT breast cancer at www.cancer.org and www.cancer.gov.

-- Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.