More than 7 percent of elderly Americans are heavy drinkers and about 9 percent of elderly drinkers are frequent binge drinkers, according to a national survey released yesterday. More than 4 percent of elderly drinkers say they consume at a binge level -- five or more alcoholic beverages -- every time they drink.

While those rates are lower than ones in recent surveys of college students, they may be even more dangerous.

That's because the elderly are more vulnerable to alcohol-induced conditions ranging from delirium to low blood pressure, and they are more likely to be taking drugs that can be harmful when mixed with alcohol.

"More older people than you ever could conceive of are drinking at levels that may be hazardous to their health," says Dr. Alison A. Moore, assistant professor of medicine at the University of California at Los Angeles and lead author of the report in this month's Journal of the American Geriatrics Society.

"People should realize that drinking gets more problematic when you're older, particularly when you're taking medications for things like high blood pressure and arthritis."

Dr. Tom Delbanco, former director of the Commonwealth/Harvard Alcohol Education and Research Program, says the new study should set off alarms: "The person who drank three to four drinks a day and never showed anything can break his hip after a glass of wine when he is old and infirmed."

The UCLA report, the most comprehensive ever on alcohol use among the elderly, was based on a national survey of 3,448 people 65 and older who took part in the first phase of the National Health and Nutrition Examination Survey.

While those figures date back to 1982, this is the first time results on elderly drinking have been published. Surveys since then suggest habits have remained consistent in the intervening years.

Among current drinkers, 77 percent drank at least once a month and 25 percent reported drinking daily, the survey found.

Nine percent of elderly drinkers said they had consumed five drinks at a sitting -- the definition of binge drinking -- at least 12 times over the last year. And more than 4 percent of elderly drinkers said they had five or more drinks every time they consumed alcohol.

Moore and her colleagues used a level of more than one drink a day to define heavy drinking for elderly women, whereas it was more than two a day for men, because women tend to have lower body weight and face a greater risk of ailments such as cirrhosis at low levels of alcohol consumption.