Background: Back pain is a common complaint in the ED. While opioids offer effective pain relief, there are concerns that opioid exposure in the ED may increase the risk of developing future aberrant prescription opioid use (AOU). The objective of this study is to measure the association between opioid administration in the ED and future AOU among opioid naïve (no prescription in prior 6 months) patients with back pain
Methods: This is a retrospective observational study of opioid naïve ED patients discharged after treatment for back pain (10/2013 to 9/2015). Patients in a university affiliated healthcare system (5 hospital EDs and 8 freestanding EDs) with an ICD 9 code for back pain were included. Electronic health records clinical data was merged with state prescription drug-monitoring program (PDMP) data. AOU was defined as opioid prescriptions from five or more different prescribers and/or pharmacies (according to PDMP) in the six months after ED visit. The association between oral and parenteral opioid administration in the ED and future AOU was estimated using logistic regression with a log link function. Relative Risks were adjusted for race, ESI, insurance, gender, and whether the patient filled an opioid prescription within 7 days of the ED visit. Patients receiving no opioids in the ED were used the reference.
Results: Of 28,835 opioid naïve patients in the study period: median age 38 (IQR:28-53); 15,929 (55%) female; 16,686 (59%)Caucasian, 11,562 (41%) had public insurance and 11,300 (39%)had commercial insurance and, overall, 5% had aberrant use after their ED visit. Opioids given in the ED: 19,622 (68%) none, 3,626 (13%)parenteral, 4,834 (17%) oral and 753 (3%) received both oral and parenteral. 13,420(47%) received an opioid prescription at discharge. The risk of AOU (vs. no opioids) for patients treated with parenteral and oral opioids in the ED was 1.55 (95%CI, 1.20-2.00) and 1.45 (95%CI, 1.15-1.82) respectively.
Conclusions: Administration of parenteral or oral opioids to ED patients with back pain is associated with a modest increased risk of future aberrant opioid use. While the study is limited by the potential of residual confounding, our finding suggest opioid exposure in the ED may trigger future opioid abuse.