Military veterans who misuse opioid painkillers are highly likely to begin using heroin as well, a 10-year study of nearly 3,400 US veterans shows.
“This study quantifies the issue of starting painkiller misuse and heroin use in a specific, high-risk population—veterans around the US,” says corresponding author Brandon Marshall, assistant professor in the Brown University School of Public Health. “Of the 500 participants who initiated heroin, 77 percent reported prior or concurrent non-medical prescription painkiller use.”
Even after statistically accounting for many other risks—such as race, income, use of other drugs, and PTSD or depression— researchers found that veterans who began misusing pinkillers were 5.4 times more likely than those who did not to begin using heroin.
Researchers studied a subset of participants in the Veterans Aging Cohort Study (VACS). In total, VACS has followed more than 7,000 HIV-infected and similar uninfected veterans engaged in care at nine Veterans Affairs facilities around the country. The overall study tracks how alcohol use, as well as concurrent medical and psychiatric disease, may affect clinical outcomes in HIV infection. As such, the study is a broad subset, but not a perfectly representative sample of all veterans.
A new analysis published in the journal Addiction focuses on 3,396 VACS participants who at the study’s beginning in 2002 said they had never used opioids for non-medical reasons or heroin. About 2,800 VACS participants had already misused painkillers or heroin when the study began, so they were not included in the analysis.
“Our findings demonstrate a pattern of transitioning from non-medical use of prescription opioids to heroin use that has only been demonstrated in select populations,” says study coauthor David Fiellin, a public health and medical professor at Yale University and director of the VACS study intervention group. “Our findings are unique in that our sample of individuals consisted of patients who were receiving routine medical care for common medical conditions.”
Though none of the veterans in the new analysis reported misusing opioids previously, a total of 1,416 had begun non-medical use of opioid painkillers by 2012. Of the 500 veterans in the study who began using heroin, 386 had also begun using prescription painkillers non-medically.
By far the best predictor in the data of who ended up using heroin was non-medical use of opioid painkillers. Other sociodemographic risk factors, controlling for all others, were being male (2.6-fold risk) or being black (2-fold risk). Abusing stimulant drugs (versus not doing so) was associated with a 2.1-fold risk of using heroin.
Receiving a short-term prescription for an opioid painkiller was associated with a less than 1.7-fold risk of starting heroin. A longer-term prescription was not significant as a risk factor at all.
Veterans clearly experience a “constellation of risks” for substance use, Marshall says. But among doctors who treat veterans, whether they are in the Veterans Affairs system or not, the findings suggest they should screen for painkiller misuse. As dangerous as that addiction can be, progression to heroin carries substantial additional dangers including contamination with other opioids like fentanyl, and injection-associated infections such as hepatitis C or HIV.
“This paper shows that, as a general clinical practice, particularly for this population which does experience a lot of chronic pain and other risks for substance use including PTSD, screening for non-medical painkiller use, whether you are prescribing an opioid or not, may be effective to prevent even more harmful transitions to heroin or other drugs,” Marshall says.
The data leaves some questions unanswered, regarding the source of the opioids that were used non-medically, why non-medical opioid painkiller use progresses to heroin use, and exactly what practices would prevent that.
The researchers are conducting several follow-up analyses, including one in which they are focusing on whether there is a significant progression from a short-term painkiller prescription to misuse to heroin—and another in which they are studying the significance of geography. Heroin prices vary widely around the country, meaning that it may not be much of a low-cost alternative to prescription painkillers in some areas of the country.
The National Institutes of Health and the US Department of Veterans Affairs supported the study.
Source: Brown University