Solitary Drug Use: Frequency, Motivations, and Overdose Prevention Strategies Employed by People Who Use Drugs

BACKGROUND: Solitary drug use increases risk for fatal overdoses by precluding bystander assistance. We must understand who uses drugs alone to tailor interventions. METHODS: We used data from 493 HIV-negative people who use drugs. Participants reported how often they used drugs alone (never, ≤half the time, >half the time) and associated motivations. We used multinomial logistic regression to identify correlates of using alone. RESULTS: 81% recently used drugs alone. High school/equivalent education (vs. <high school; relative risk ratio[RRR] = 2.90, 95% Confidence Interval[CI]:1.65-5.09), some college education or more (vs. <high school; RRR = 1.94, 95%CI:1.16-3.23), homelessness (vs. housed; RRR = 1.42, 95%CI:1.0-1.92), cocaine use (vs. no cocaine use; RRR = 3.51, 95%CI:1.13-10.86), and experiencing physical violence (vs. no violence; RRR = 2.19, 95%CI:1.02-4.71) were associated with using alone ≤ half the time versus never. Hispanic/multiracial/another racial identity (vs. Black; RRR = 2.45, 95%CI:1.34-4.50), high school/equivalent education (vs. <high school; RRR = 2.35, 95%CI:1.20-4.60), cocaine use (vs. no cocaine use; RRR = 3.51, 95%CI:1.13-10.86), and experiencing physical violence (vs. no violence; RRR = 1.79, 95%CI:1.22-2.62) were associated with using alone > half the time versus never. Common motivations were comfort, safety, and not having to share drugs. CONCLUSIONS: Interventions that promote comfort and safety for people who use drugs may increase willingness to engage in harm reduction strategies while using alone.