This retrospective study examined factors associated with nonmedical opioid use among 208 heroin-abusing research volunteers in the metropolitan Detroit area. Drug and medical history data were obtained from structured questionnaires administered during screening for behavioral pharmacology research studies. Analyses included demographic data (gender and race), history of drug use (prescribed, nonmedical, and route of use), and potentially relevant medical conditions (e.g., pain). All volunteers (mean age=43 years) reported chronic heroin use (mean duration=21 years), with 66% currently injecting heroin. Two multiple logistic regression analyses were used to identify factors related to lifetime and current nonmedical opioid use (predicted variables). Odds ratios (ORs) from logistic regression--which predicted membership in lifetime heroin use only (n=52) versus heroin plus nonmedical opioid use (n=156) groups--indicated that nonmedical opioid use was significantly associated with legitimate prescription opioid use (OR=10.5), having ever sought treatment for heroin use (OR=4.21), and a history of lung problems (OR=3.66) and dental pain (OR=2.58). The finding of a significant positive association (R(2)=.83) between lifetime rates of medical and nonmedical use of specific opioids in this study is consistent with previous observations that prescription opioid use or availability is a prominent risk factor for nonmedical opioid use. A limitation of this study is that age-of-onset data were not originally collected; thus, the relative (predictive) order of pain conditions, medical use, and nonmedical use of opioids cannot be determined retrospectively.
