The newer wave of injection drug users (IDUs) are more likely to have first abused prescription opioid pills, or painkillers, than those who have been injecting drugs longer. And although a recent study found that IDUs who were initially addicted to painkillers have a lower HIV rate than those who were not, the newer IDUs are nonetheless at high risk for the virus.

Centers for Disease Control and Prevention (CDC) researchers analyzed data from the 2015 National HIV Behavioral Surveillance study, looking at survey responses from adult IDUs who injected opioids, including heroin.

The CDC’s Dita Broz, PhD, MPH, presented findings from the study at the 2017 Conference on Retroviruses and Opportunistic Infections (CROI) in Seattle.

Dita Broz of the CDC at CROI 2017 in SeattleBen Ryan

Of the 7,454 IDUs in the study, 2,208 (30 percent) said they used prescription painkillers before they began to inject drugs. The IDUs who began injecting more recently were more likely to have been hooked on painkillers first, including 12 percent, 27 percent, 39 percent, 51 percent and 49 percent of those who started injecting before 1995, between 1995 and 1999, between 2000 and 2004, between 2005 and 2009, and between 2010 and 2015, respectively.

After controlling the data for age, race and ethnicity, the researchers found that compared with those who were not first prescription pill abusers, those IDUs who were initially hooked on prescription opioids were 2.5 times more likely to have started injecting drugs in 2000 or after than those starting before that year, 1.1 times more likely to be female, 1.7 times more likely to be white than those who were nonwhite, 1.2 times more likely to have been homeless during the previous year and 40 percent less likely to be HIV positive. (A respective 2 percent and 6.3 percent of those who were first hooked on painkillers and those who were not tested positive for the virus.)

Among those who used prescription opioids prior to injecting drugs, 30.5 percent first obtained them with a physician’s prescription; 20.1 percent obtained them from friends without money changing hands; and 19.7 percent purchased them from friends, family or others.

The average time between the first use of prescription opioids and the first use of injection drugs was 5.4 years.

Among those who used prescription painkillers prior to injecting drugs, the first injected drug was heroin for 76.3 percent, prescription opioids for 10.1 percent, cocaine or a speedball (a combination of cocaine and heroin or cocaine and morphine) for 8.1 percent and methamphetamine for 4.3 percent.

To read a POZ feature on the uncertain future of syringe services programs under Trump, click here.