A study from the New York Department of Mental Health and Hygiene reports that 25 percent of sexually active gay men in New York City engage in binge drinking, and that this behavior may be responsible for more H.I.V. transmission than drug use, the New York Times reported Jan. 5.

Approximately 15 percent of adults in New York City binge drink -- defined as having five or more drinks on one occasion -- at least once a month. The report, titled "Alcohol Use and Risky Sex in New York City," said that binge drinkers were 50 percent more likely than non-binge drinkers -- and three times more likely than non-drinkers -- to have two to four sexual partners in the past year.

Moreover, 40 percent of sexually active gay men who engage in binge drinking said they had five or more sex partners in the past year, compared with 21 percent of gay men who do not binge drink.

"Heavy drinkers are more likely to have multiple partners," said Thomas Frieden, the New York City Health commissioner, "increasing their risk of H.I.V., other STDs, and unplanned pregnancy."

The study also investigated binge drinking in the teenage population, reporting that 14 percent of teenagers engaged in binge drinking in the past 30 days (65 percent said they did not drink at all). The report noted that teenagers who used alcohol in any amount were more likely to have multiple sex partners and to have caused a pregnancy, and were less likely to use condoms.