Heroin users are much more likely to be older, whiter and suburban compared with 50 years ago, a new study concludes.
They are almost evenly split between men and women, The Washington Post reports.
Fifty years ago, 83 percent of those seeking treatment for heroin use were men.
In 2010, three-quarters of people who used heroin did so after abusing prescription opioids, the researchers wrote in JAMA Psychiatry.
In the 1960s, more than 80 percent of people seeking treatment said heroin was the first opioid they had used. The findings come from a survey of patients in 150 treatment programs around the nation.
The study found 90 percent of people seeking treatment for heroin use in 2010 were white, compared with just over 40 percent in the 1960s. The average age increased from 16.5 years old 50 years ago, to 22.9 years old in 2010.
Among those who said they started with an opioid painkiller and switched to heroin, 98 percent said they preferred the high heroin gave them, and 94 percent said heroin was cheaper and easier to get.
"In the past, heroin was a drug that introduced people to narcotics," lead researcher Theodore J. Cicero, PhD, of Washington University School of Medicine in St. Louis said in a news release. "But what we're seeing now is that most people using heroin begin with prescription painkillers such as OxyContin, Percocet or Vicodin, and only switch to heroin when their prescription drug habits get too expensive."
OxyContin was reformulated in 2010 to make it more difficult to crush or dissolve, leading some people to switch from abusing the drug to heroin, Cicero said. "If you make abuse-deterrent formulations of these drugs and make it harder to get high, these people aren't just going to stop using drugs," he noted. "As we made it more difficult to use one drug, people simply migrated to another. Policymakers weren't ready for that, and we certainly didn't anticipate a shift to heroin."