Addressing multiple overdoses: opportunities for prevention and innovation

Fatal and nonfatal drug overdose (NFOD) is common and increasing globally (Fact Sheet: Opioid Overdose, 2020). Preliminary data from the United States show that against the backdrop of the global Covid pandemic, there is likely to be an even greater surge in the time to come (Ahmad et al., 2021; Friedman & Akre, 2021). Globally, more than 70% of fatal drug overdose deaths involve opioids. One of the most significant risk factors for fatal overdose is prior nonfatal opioid overdose (Krawczyk et al., 2020; Olfson et al., 2018). Nonfatal opioid overdose provides an opportunity for identification and interventions such as naloxone and medications for opioid use disorder (buprenorphine and methadone) to mitigate future risk and provide protection against both opioid-related and all-cause mortality (Larochelle et al., 2018; Walley et al., 2013).

In this issue of International Journal of Drug Policy, Geddes et al. examined the prevalence of and risk factors for multiple NFOD among individuals who participated in the 2019 Australian Needle and Syringe Program Survey. Eligible participants reported a NFOD in the prior 12 months and injection of an opioid at the most recent NFOD. In a cohort of 222 individuals, 59% were male, 39% were under 39 years-old, 23% were Indigenous, 73% had used heroin at the last NFOD, and 48% had multiple NFOD (median 3, IQR 1–6). In adjusted analyses, the authors found that public injecting and benzodiazepine use in the 12 hours prior to NFOD were risk factors for multiple NFOD compared to individuals with a single nonfatal opioid overdose in the prior 12 months.

These findings have important implications for how to address recurrent NFOD and reduce mortality. First, there is an urgent need to continue to expand access evidence-based and life-saving interventions, such as low barrier access to medications for opioid use disorder and naloxone. However, there are other significant opportunities to reduce overdose risk identified by Geddes et al. The authors found that public injection was a risk factor for multiple overdose in this study; however, only 7% of the sample reported using at a safer injection facility (SIF). SIFs are associated with reduced overdose death rates but have faced challenges in widespread implementation (Burris et al., 2020). For example, after implementation of Canada’s first SIF in Vancouver, the surrounding overdose death rate decreased 35% relative to elsewhere in the city (Marshall et al., 2011). Future expansion and uptake of this critical overdose prevention intervention is needed globally. The authors also found that benzodiazepine use in the prior 12 hours was also a risk factor for multiple overdoses. Training for people who use drugs to reduce overdose risk includes advice to minimize polysubstance use. Although this is reasonable advice, for some people it may not be possible and so additional recommendations such as using with other people, testing small amounts of a drug first, and calling emergency services in the setting of an overdose are critical.

Other interventions that can reduce first-time and recurrent overdoses include safer supply policies and enhanced access to drug checking and fentanyl test strips (FTS). Safer supply is the legal, regulated supply of drugs usually only attainable through an illicit market, where the risk of contamination is high and drug doses are unpredictable (Fleming et al., 2020). In this sample, 8% of respondents believed that their most recent overdose was the result of a contaminated supply. Safer supply would provide a reliable, known product to people who use drugs. In addition, drug checking is a harm reduction tool that provides information to people about the dose and ingredients of drugs, the testing and analysis is done at stationary testing locations. Although drug checking has the potential to provide valuable data that could reduce harms, there are concerns about the implementation of these services depending on local drug laws(Wallace et al., 2020). Finally, FTS are a form of drug checking that an individual can do on their ow. FTS can detect fentanyl in drug samples diluted in water. They have been found to be feasible and acceptable to people who use drugs, although also remain poorly implemented(Peiper et al., 2019).

In addition to improving implementation of overdose reduction intervention, tailoring them based on gender, race, and ethnicity is critical. Collins et al. recently highlighted the importance of moving beyond “gender neutral approaches” to the overdose crisis(Collins et al., 2019). They highlight that cisgender, two spirit, and transgender women face differential impact of drug related harms. Harm reduction services should therefore seek to mitigate that impact and address barriers such as stigma, trauma, and violence(Collins et al., 2019). Similarly, to reduce health inequities, it is critical that future studies and incorporate race and ethnicity to ensure a focus on the needs of Indigenous people and people of color. Indigenous people and people of color should be centrally involved in all phases of harm reduction services development, including planning, rollout, evaluation, and improvement.

Finally, other medical consequences of opioid overdose are also important to consider. A recent scoping review by Zibbell et al.(Zibbell et al., 2019) identified health consequences of NFOD that can have a significant impact on morbidity and mortality. These include overdose-induced hypoxic injury resulting in kidney failure, cardiac complications, and stroke, among others. Such sequalae highlight the importance of cross-collaboration across healthcare settings. Providers in all fields must be prepared and trained to intervene at the time of a NFOD or when treating the sequalae of NFOD.

NFOD continues to have a major impact globally. This study by Geddes et al. contributes to our understanding patterns of recurrent overdose and associated risk factors. This is a key step in offering interventions to people to reduce the morbidity and mortality from opioids.