Men and women who inject drugs live with different risks of acquiring infections such as HIV, yet research that assesses gender-specific risks has historically been scarce. Understanding these differences is key to reducing the harms of injection drug use and facilitating effective interventions.
For example, compared to men, women are more likely to share needles and injection equipment. Reasons for this include more women than men begin injecting drugs in social settings like in romantic relationships or friend groups. Women also have higher rates of some underlying mental health conditions, such as depression, anxiety, and post-traumatic stress disorder (PTSD), that are linked to increased needle sharing. This makes women who use drugs particularly vulnerable to infection and disease.
Meanwhile, men have higher overall rates of substance use disorders and are more likely to overdose or need emergency care.
Understanding gender-based differences in injection drug behavior is critical. Especially now during the COVID-19 pandemic, overdose deaths in the United States increased to 100,000 people between April 2020 to April 2021 — a 30 percent increase from the twelve months prior. Studying the differences in injection drug risk behaviors between men and women can guide targeted public health responses.
A new study in the Journal of Addiction Medicine used data collected from an urban safety net hospital on injection drug behaviors among men and women to assess associated risks.
The study’s authors are Breanne Bondi, MPH, a researcher at Boston University School of Public Health (BUSPH) Department of Health Law, Policy, and Management (HLPM), Brad Anderson, PhD, from Butler Hospital, Kristina Philips, PhD, from Kaiser Permanente Center for Integrated Health Care Research, and Michael Stein, MD, from BUSPH HLPM.
Participants (n = 252) were recruited from 2014 to 2018 for a randomized trial aimed at reducing infections for people who inject drugs. Patients self-identified their gender, and all data were collected via interview. The study assessed behaviors such as sharing needles or injection equipment, employment and caregiver status, substance use disorder severity, opioid use disorder treatment, mental health history, and engagement in transactional sex.
The main analyses of the study used the Risk Assessment Battery (RAB) drug score, which quantifies drug-related HIV risk behaviors and the number of times in the past three months that participants injected with a previously used needle. The RAB is an eight-question assessment with a total score of 0 to 22, with higher scores indicating greater occurrence of the behaviors. Additionally, researchers asked participants to specify how often they used needles previously used by someone else to confirm directionality.
These variables were measured against independent variables such as age, race, homelessness, caregiver status, and injection partners. (“Injection partners” was categorized as the number of times the participant injected alone, with romantic partners, or with non-romantic partners.)
Multiple linear regression models were used to analyze the RAB score against injection partners and other covariates. A negative binomial regression (a generalization of the Poisson regression) measured the association between the number of times the participant injected with a used needle, injection partners, and other covariates. Separate models were run for men and women to observe gender-based differences.
Women had significantly higher RAB drug risk scores than men and were more likely to inject with a previously used needle. Compared to men, women were less likely to inject alone and more likely to inject with a sexual partner. Both men and women who reported injecting with a sexual partner were more likely to report injecting with used needles compared to participants who injected alone.
Women in this study also had higher rates of PTSD (which aligns with previous research), depression, opioid dependence, and were more likely to report transactional sex than men. Men were more likely to experience homelessness. Employment impacted drug injection behaviors slightly differently among men and women. Women who were employed were less likely to inject with a previously used needle. Men who were employed shared fewer needles and equipment with others; thus, employment among men who inject drugs may be protective to other people in their network.
The study has some limitations. Participants were recruited from an urban safety-net hospital, and the results may not be generalizable to other populations. Additionally, the sample size and self-reported nature of the study may impact reliability. Notwithstanding these limitations, this study supports previous evidence that men and women exhibit different risks behaviors related to injection drug use.
These findings upheld that injecting drugs in a relationship setting is especially concerning for women. Women who inject in the context of a relationship are especially likely to share needles, and thus are more prone to injection-related infections. This implies that targeting dyads who inject drugs is important for reducing needle sharing behavior, particularly for women. Needle exchanges and other harm-reduction services should prioritize these dyads for additional education and support.
People who inject drugs face many barriers to obtaining and maintaining employment such as stigma, decreased productivity, and institutionalized abstinence-only policies (“drug-free workplaces”). This study highlights how increasing stable employment for men and women who inject drugs is linked to fewer risk behaviors. Specifically, employment was associated with women using fewer previously used needles and with reductions in men sharing needles or equipment with others. These findings demonstrate how stable employment can be a powerful protective and mitigating factor, suggesting policymakers should lean into employment as a harm reduction strategy.
Fleshing out gender-based risk behaviors among people who inject drugs can inform tailored harm-reduction interventions. This may lead to better engagement with services, which is critical to addressing the current overdose and addiction crisis.