News in brief - April 17, 2006

Too much, too little sleep linked to type 2 diabetes - FDA panel advises against black-box warning for ADHD drugs - Oral antibiotics for swimmer's ear get thumbs down - Avian flu vaccine elicits immune system response - Analysis finds scant evidence of omega 3 health benefits - New source found for key Tamiflu ingredient

Too much, too little sleep linked to type 2 diabetes

Men who sleep more than eight hours a night have three times the risk of developing type 2 diabetes than those who sleep about seven hours. Those who sleep only five or six hours a night have double the risk, according to a study published in the March issue of Diabetes Care.

Researchers with Yale University School of Medicine in Connecticut analyzed data from more than 1,700 men enrolled in the Massachusetts Male Aging Study from 1987 to 2004. Even after controlling for age, hypertension, tobacco use, self-rated health status, education and waist circumference, the risk remained.

Studies have linked short-term sleep deprivation to significant changes in metabolic and endocrine function, and the authors suggest sleep duration might be an independent risk factor for this disease over the long term.

"Although lifestyle changes such as weight loss and increasing physical activity are the cornerstone of diabetes prevention, efforts are needed to better understand other determinants of the disease and to develop additional prevention strategies," the authors wrote.

FDA panel advises against black-box warning for ADHD drugs

A Food and Drug Administration advisory panel decided March 22 against recommending that a black-box warning be placed on labels for several stimulant drugs often prescribed for children and adults with attention-deficit/hyperactivity disorder. Although certain adverse events were identified by the committee, most notably hallucinations and psychotic episodes, the risk level did not rise to the need for a black-box warning, said Robert Nelson, MD, PhD, chair of the Pediatric Advisory Committee and attending intensivist at Children's Hospital of Philadelphia.

The FDA's Drug Safety and Risk Management Advisory Committee had recommended in February that a black-box warning for cardiovascular risk be placed on such drugs as Adderall, Ritalin and Concerta. While a warning of possible heart risks posed by the medications was considered, the pediatric committee ultimately decided stimulants pose a lower risk for most younger patients than for adults.

Because the FDA is changing the way medication labels are organized to highlight important safety considerations, necessary precautions could likely be taken care of in the re-ordered labels, said Dr. Nelson.

A guide to help parents understand the risks posed by the drugs likely will be forthcoming, said Robert Temple, MD, director of FDA's drug evaluation center's Office of Medical Policy. The FDA will determine whether a black-box warning is appropriate.

Oral antibiotics for swimmer's ear get thumbs down

Topical antibiotics should be used for diffuse acute otitis externa, also known as swimmer's ear, but physicians should avoid using systemic antimicrobials unless the infection goes beyond the ear canal or there are other specific factors that indicate the need for these drugs. These recommendations are in guidelines issued by a panel of specialists and primary care doctors convened by the American Academy of Otolaryngology -- Head and Neck Surgery Foundation.

In addition, pain associated with the infection should be assessed and treated with appropriate analgesics. These are the first guidelines for the care of this type of ear infection.

"Orally administered antibiotics have significant adverse effects. ... Societal consequences include direct transmission of resistant bacterial pathogens in homes and child care centers," the authors wrote.

Avian flu vaccine elicits immune system response

A vaccine created from an inactivated H5N1 avian influenza virus might provide effective protection against this bug, according to a study paid for by the National Institute of Allergy and Infectious Diseases and published in the New England Journal of Medicine March 30.

Researchers randomized more than 400 healthy adults to receive either two doses of this vaccine in varying amounts or a placebo. Those who received two shots of 90 micrograms of vaccine, the highest dosage, had the most robust immune system response. Mild pain at the injection site was the most common adverse event. No severe reactions were reported.

Authors suggested lower doses of vaccine might be sufficient to generate a response capable of defending against this virus and that dose-sparing approaches should be pursued aggressively. In the case of a pandemic, it might not be possible to produce enough vaccine for everyone to receive large amounts of vaccine.

"We are working hard to address the many challenges that remain with regard to the development of an H5N1 vaccine," said NIAID Director Anthony S. Fauci, MD. "We are investigating other options that may allow us to reduce the dosage ... so we can achieve a more practical immunization strategy."

Analysis finds scant evidence of omega 3 health benefits

Little evidence of the importance of omega 3 fats to health was uncovered during an analysis of 89 studies by British researchers. Their findings were published online March 25 in the British Medical Journal. While the findings do not rule out the beneficial effects of the fats, the evidence should be reviewed regularly, they caution.

Consumption of long-chain omega 3 fatty acids found in oily fish and a shorter-chain omega 3 found in some plant oils is thought to protect against heart disease. But pooling the results of many studies produced no strong evidence that omega 3 fats have an effect on total mortality or combined cardiovascular events, said the researchers.

Despite their findings, the researchers recommend the continuation of guidelines advising the consumption of fish, because other studies have found benefits to omega 3 fats.

New source found for key Tamiflu ingredient

Scientists have found another source of shikimic acid, an important material for the production of Tamiflu (oseltamivir phosphate), taking the pressure off the Chinese star anise, from which most of the ingredient had been derived and which was fast disappearing in nature. The seeds of the sweet gum tree, which grows widely throughout the United States, also contains abundant amounts of shikimic acid, according to findings to be released April 9 at the American Chemical Society's annual meeting.

There is a skyrocketing demand for Tamiflu throughout the world as nations stockpile the antiviral drug to help treat people if a pandemic flu should occur.