Alcohol problems affect almost 33 million American adults and most have never sought treatment, according to a government survey that suggests rates have increased in recent years.

The study is the first national estimate based on a new term, “alcohol use disorder,” in a widely used psychiatric handbook. It defines problem drinkers or those with the disorder as people with at least two of 11 symptoms, including drinking that harms performance at work, school or home, frequent hangovers, failed attempts to limit drinking and cravings.

Researchers from the National Institute on Alcohol Abuse and Alcoholism asked 36,000 adults during 2012 and 2013 about lifetime drinking habits. About 14 percent were current or recent problem drinkers, or nearly 33 million nationally, and 30 percent — almost 69 million — had been problem drinkers at some point in their lives.

Nearly 40 percent of adults surveyed said they had engaged in binge drinking — downing at least five drinks in a day at least once in the past year, up from 31 percent in the earlier survey. Drinking that was even heavier also increased but was less common.

Drinking problems were most prevalent among men, whites and Native Americans. Low-income adults, those younger than 30 and those who had never married also had relatively high rates. Problem drinking also was more common among city dwellers than those in rural areas, while the West and Midwest had higher rates than other regions.

George Koob, director of the federal agency that did the survey, said it’s unclear why problem drinking has increased but that many people underestimate the dangers of excessive alcohol. Many won’t seek help because of “stigma and denial,” he said, and many don’t realize that medications and behavior treatments can help.

“There’s a lore that there’s only Alcoholics Anonymous out there, and that’s not true,” he said.