Low Knowledge of HIV PrEP Among Injection Drug Users

HIV infects and destroys the immune system after being spread through contact with HIV-infected bodily fluids. In the United States, it most commonly spreads by anal or vaginal sex or by sharing drug injection equipment.¹

When thinking about ways to reduce the risk of HIV infection, what often comes to mind is to engage in safe sex practices and never share drug injection equipment.¹ However, many patients aren’t aware of another prevention option: pre-exposure prophylaxis (PrEP).

PrEP involves taking emtricitabine/tenofovir (Truvada or Descovy) to prevent high-risk individuals from contracting HIV. When taken as indicated, PrEP is highly effective, reducing the HIV risk from sex by 99% and from injecting drugs by at least 74%.² 

In a study published in the January 2022 issue of Open Forum Infectious Diseases, a team of researchers from the Division of Infectious Diseases at Washington University School of Medicine evaluated baseline knowledge, opinions, and interest in PrEP among persons who inject drugs (PWID). More specifically, they interviewed 30 PWID hospitalized for serious injection-related infections (e.g., endocarditis, osteomyelitis).³

Researchers found low overall awareness of PrEP. Only 2 study participants were already on PrEP and only 5 had heard about it previously.

Participants didn’t view HIV as a significant threat. They associated injection drug use (IDU) with a minimal risk of HIV transmission, perceiving it to be primarily a sexually transmitted infection (STI) that mostly affects men who have sex with men (MSM).

Researchers educated participants about HIV risk from IDU and PrEP as a valuable prevention method. However, participants expressed no interest in PrEP.

Many believed PrEP was exclusive to MSM. They mentioned other methods, such as abstaining from IDU or using clean needles, were more effective in lowering their HIV risk. Notably, all participants had access to opioid use disorder treatments and needle exchange programs, which may have skewed their overall perception.

Despite high knowledge of harm reduction techniques with needle use, participants had a high STI rate (17%). This suggests that not all STIs among PWID are directly related to injecting but could be related to sexual behaviors and impaired judgement. None of the participants made the connection that a prior STI increases their risk of HIV infection.

Conclusion

This study found PWID had low baseline knowledge of PrEP, high stigma with PrEP, and little interest in starting PrEP even after education. This highlights the need to incorporate PrEP education more effectively in PWID. Pharmacists are well-positioned to address questions, concerns, and misconceptions that patients have about PrEP.

About the Author

Natalie Espeso is a 2022 PharmD candidate at the University of Connecticut.

References

1. HIV and AIDS: The Basics. HIVinfo.NIH.gov. Updated August 16, 2021. Accessed January 13, 2022. https://hivinfo.nih.gov/understanding-hiv/fact-sheets/hiv-and-aids-basics
2. Pre-Exposure Prophylaxis. HIV.gov. Updated January 07, 2022. Accessed January 13, 2022. https://www.hiv.gov/hiv-basics/hiv-prevention/using-hiv-medication-to-reduce-risk/pre-exposure-prophylaxis
3. Sayood S, Marks LR, Patel R, Nolan NS, Liang SY, Durkin MJ. Low Knowledge of HIV PrEP Within a Midwestern US Cohort of Persons who Inject Drugs. Open Forum Infect Dis. 2022;9(1):ofab541. doi:10.1093/ofid/ofab541