Older adults just as likely to drink to excess

ALCOHOLISM

Alcohol is the most commonly abused substance in the United States, with nearly 10 percent of Americans drinking to excess - and a new study finds the problem is just as prevalent among older people. Although screening for alcohol abuse is a routine practice at the doctor's office, drinking problems in the elderly are frequently missed, often because clinicians are less likely to suspect alcohol abuse in this population. To examine just how common unhealthy drinking is in older adults, lead author Elizabeth Merrick from the Heller School for Social Policy and Management at Brandeis University studied data from the Medicare Current Beneficiary Survey, which provided self-reported information on alcohol use by adults aged 65 and older from across the nation. Researchers used federal guidelines to define unhealthy drinking in older adults as more than 30 drinks per month or more than four drinks on any given day. They found that 9 percent of the elderly were unhealthy drinkers, while about two-thirds of the aging population didn't drink at all. "This brings to light the issue that its not unusual for the elderly to exceed drinking guidelines," said Merrick, suggesting a renewed focus is warranted in screening for alcohol use in older adults.

BOTTOM LINE: Unhealthy alcohol consumption is more common among older Americans than previously thought. Screening for alcohol abuse will be especially important in this population, given a higher susceptibility to illness and interactions of alcohol with medications.

CAUTIONS: Survey participants tend to under-report alcohol use, so these data could underestimate actual drinking rates.

WHAT'S NEXT: Researchers plan on studying whether the drinking problems of older adults are overlooked by their doctors.

WHERE TO FIND IT: The Journal of the American Geriatrics Society, Feb.

SUSHRUT JANGI

ENTOMOLOGY

Researchers may finally be on the way to discovering how DEET works to repel mosquitoes and other insects. DEET, a small synthetic, organic compound, was discovered 50 years ago by US Army-funded researchers looking for a repellent to protect overseas soldiers from malaria and other insect-borne diseases. Researchers guessed that the chemical somehow disrupted an insect's ability to smell human beings, but they never understood exactly how it worked. Now, scientists, supervised by Mathias Ditzen at The Rockefeller University in New York, have pretty much figured it out: DEET apparently blocks a mosquito's ability to smell human odor. Mosquitoes hunt down humans by sensing carbon dioxide in breath and body odor through special sensory organs located on their heads. Researchers first tested the electrophysical activity of a cell in the organ that senses CO{-2} in breath and found that the level of activity remained the same in the presence of DEET. Then, they measured the level of activity in the cells that sense human odor and recorded less activity in the presence of DEET - suggesting that this is the mechanism by which the chemical stops mosquitoes. Researchers further found that when they tested flies that lacked the smell gene OR83b - a gene found in all insects - the DEET was no longer effective.

BOTTOM LINE: "We now know that DEET does not exactly repel mosquitoes and other insects because it smells bad," said Leslie Vosshall, the study's lead author. "Rather, the chemical deters insects by disrupting their ability to smell body odor by somehow blocking the smell gene."

CAUTIONS: The paper does not explain exactly how DEET blocks the function of the OR83b gene.

WHAT'S NEXT: The researchers want to find new compounds that work like DEET and are safer to use.

WHERE TO FIND IT: Science, March 13

SENA DESAI GOPAL