Researchers uncover factors that lead prescription opioid misusers to heroin

The connection between misuse of prescription opioids and eventual transition to heroin use remains controversial, with federal leaders recently trying to deflect the widely held notion that governments' crackdown on prescription access caused a surge in heroin use. Yet an important question for research involves whether certain factors can predict the likelihood that a non-medical user of opioids will turn to heroin.

In the first of two planned papers, researchers at Wright State University report that in a group of young-adult prescription opioid users with no dependence history, factors such as early first use and use to get high (as opposed to self-medicating) were associated with greater risk of transtioning to heroin. The strongest risk factor that was identified, however, was non-oral administration of prescription opioids, says the study's lead author.

“This illustrates some targets for intervention,” says Robert G. Carlson, PhD, director of the Center for Interventions, Treatment and Addictions Research at Wright State's Boonshoft School of Medicine. “One message would be, 'If you find yourself having come to the point where you've started snorting your pills, you've really crossed the threshold.'”

The paper on transition to heroin use has been published online in Drug and Alcohol Dependence. A second paper, on the variables that lead non-medical opioid users to opioid dependence, will follow.

Study parameters

The 36-month study involved nearly 400 young adults ages 18 to 23 in the Columbus, Ohio area; all were non-medical users of pharmaceutical opioids but were not opioid-dependent and had no history of heroin use. Carlson says about three-quarters of the population reported using prescription opioids two or fewer days a week. Questionnaires were administered to participants at baseline and every six months for 36 months, with a primary focus on the outcome of the time from initiation of illicit opioid use to initiation of heroin use.

In a surprising finding, while only around half of the study sample was white, all participants who transitioned to heroin use were white; there were no African-American heroin users in the study.

Carlson says this finding bears more thorough analysis in the future—why there was such an imbalance remains unclear. The paper does state, however, “When asked why there are comparatively lower levels of heroin use among non-whites, a treatment provider in Columbus … suggested that a long history of heroin use in African-American communities may have engendered negative views about heroin use among younger generations.”

Factors that most all or heroin users in the study had in common included OxyContin use at some point in their lifetime, non-medical use of opioids to get high, and non-oral administration of pharmaceutical opioids (sniffing or snorting).

Carlson says that the findings contribute numerous science-based ideas that should inform prevention efforts. As the study paper states, “Our results suggest that preventing transition to non-oral pharmaceutical opioid use, preventing transition to opioid dependence, … and educating [pharmaceutical opioid] users about the risks involved in reasons for use among those non-opioid dependent are important intervention targets.”