By Brian MacQuarrie GLOBE STAFF MAY 16, 2015

Nearly three-quarters of Massachusetts adults believe heroin use is an extreme or very serious problem in the state, and almost four in 10 adults know someone who has abused prescription painkillers in the last five years, according to a survey by The Boston Globe and the Harvard T.H. Chan School of Public Health.

The poll also found that Massachusetts residents are more worried about opioid abuse than are Americans generally, and that more adults here believe prescription drug abuse is getting worse.

Despite increased awareness of the problem, just 36 percent of adults in Massachusetts said they have been warned by doctors about the risk of painkillers prescribed to them, the survey found. Nationwide, 61 percent of respondents said they had been cautioned.

The surveys, conducted separately in Massachusetts and nationwide between April 7 and 19, are believed to be among the first to gauge public perceptions of opioid abuse, said Robert J. Blendon, a Harvard School of Public Health professor who codirected the poll.