Perceived Severity of and Susceptibility to Overdose Among Injection Drug Users: Relationships With Overdose History.

Background: Overdose is relatively common among injection drug users (IDUs) yet little is known about how overdose-related health beliefs influence overdose experiences or risk reduction. Objectives: This study examines the association of perceived susceptibility to and perceived severity of nonfatal overdose with overdose history among IDUs attending needle exchange programs (NEPs) to inform prevention efforts. Methods: In 2009–2010, IDUs (N = 91) attending NEPs completed self-report surveys. Negative binomial regression modeled the association between demographics, age of injection initiation, length of time attending the NEP, perceived severity of overdose, and perceived susceptibility to overdose with lifetime history of nonfatal overdose. Results: Over half (55%) of participants reported lifetime overdose, with a mean of 2.9 overdoses. A multivariable negative binomial regression model revealed that younger current age, older age of first injection, non-Caucasian race, higher perceived severity of overdose, and lower perceived susceptibility to overdose were significantly correlated with fewer lifetime overdoses. Conclusions: Although our methodology precludes causal inferences, these findings are consistent with the hypothesis that perceived severity and perceived susceptibility are among several factors associated with IDUs' use of protective behaviors, which could influence the likelihood of overdose. Future prospective research to explore the impact of this and other health beliefs on risk behaviors and overdose could help improve the effectiveness of behavioral interventions. [ABSTRACT FROM AUTHOR]