News in brief - Jan. 26, 2004

FDA says no to silicone gel implants - Vitamin D could decrease risk of multiple sclerosis - Western medicine studies Eastern herbal remedy for jaundice - Adult-onset asthma may be different from child-onset asthma

FDA says no to silicone gel implants

The Food and Drug Administration effectively barred silicone gel breast implants from re-entering the marketplace until additional data are gathered by the manufacturer. The agency took this action in a Jan. 8 draft guidance despite a recommendation last fall by one of its advisory panels that the agency approve the sale of implants for widespread use.

Since 1992, the silicone implants have only been used for breast cancer patients participating in clinical trials because of concerns that silicone leaking from implants caused serious health problems.

The FDA is recommending that testing be done to determine how long silicone implants will last before rupturing in the body and that modes and causes of rupture be addressed.

Implants filled with saline, which is considered more safe than silicone gel, continue to be available.

Vitamin D could decrease risk of multiple sclerosis

Women who take a multivitamin containing vitamin D were less likely to develop multiple sclerosis than women who did not take the supplements, according to a study published in the Jan. 13 Neurology, the scientific journal of the American Academy of Neurology.

"Because the number of cases of MS increases the farther you get from the equator, one hypothesis has been that sunlight exposure and high levels of vitamin D may reduce the risk of MS," said Harvard School of Public Health researcher Kassandra Munger. "This is the first prospective study to look at this question."

Although the findings await confirmation through additional research, "It's exciting to think that something as simple as taking a multivitamin could reduce your risk of developing MS," she said.

The researchers examined data from the 20-year Nurses' Health Study and the 10-year Nurses' Health Study II. Women's diets and use of multivitamin supplements were assessed as the studies began and then again every four years. There were 187,563 women in the study. Of those, 173 developed MS during the course of the study.

Western medicine studies Eastern herbal remedy for jaundice

Jaundice in infants is common and, in Western nations, is usually treated with exposure to light. But a study in the Jan. 1 Journal of Clinical Investigation suggests that a drug therapy could be on the horizon.

Researchers from Baylor College of Medicine in Texas, demonstrated that a Chinese herbal tea remedy for jaundice, called yin zhi huang, activates a liver receptor that enhances the clearance of bilirubin. YZH was "boiled down" to one component: 6,7-dimethylesculetin, which binds to and activates the hepatic nuclear receptor CAR and its target genes, leading to increased clearance of bilirubin.

"This is a wonderful example of knowledge gained by applying the Western scientific method to an Eastern herbal remedy," said Mitchell Lazar, MD, PhD, chief of the Division of Endocrinology, Diabetes and Metabolism at the University of Pennsylvania School of Medicine, Philadelphia, in an accompanying commentary. "It will be very exciting if a pure compound emerges from the tea leaves as a pharmacological therapy for neonatal jaundice that is complementary to the current Western practice of phototherapy."

Adult-onset asthma may be different from child-onset asthma

Allergies are more common in asthmatics whose disease starts in childhood but those who develop the condition when they are older lose lung function faster, according to a paper published in the January Journal of Allergy and Clinical Immunology.

Researchers at National Jewish Medical and Research Center in Denver studied 80 patients with severe asthma for allergen sensitivity and lung function. Those who developed the disease before age 12 were more likely to wheeze when exposed to dust and pollen and were more likely to have had a history of eczema. Those who developed the disease after age 12 had worse lung function despite being asthmatic for a shorter period.

Authors of the paper suggested that differentiating among forms of asthma may lead to better treatment options.

"Asthma has traditionally been very broadly defined in terms of symptoms rather than underlying biological processes," said Sally Wenzel, MD, lead investigator and a pulmonologist at the center. "Our research helped divide these severe asthma patients into four subsets. We believe these subsets represent different biological processes."