176 Emergency Department Utilization after Emergency Department-Initiated Buprenorphine

Abstract

Concerns about increased emergency department (ED) utilization after ED-initiated buprenorphine (EDBI) is often cited as a concern when starting ED buprenorphine programs, but to our knowledge there has been no literature supporting this idea. In response, we aimed to answer the following questions: 1. Do patients who undergo (EDIB) have a change in their number of ED visits before and after EDIB? 2. Do patients who undergo EDIB have a change in their number of opioid-related ED visits before and after EDIB? We enrolled patients who received ED-initiated buprenorphine to treat opioid use disorder who presented to our urban, academic ED between December 11th, 2017 and October 10th 2018. Consenting patients were followed prospectively and our electronic medical record (EMR) was queried for the number of ED visits in the 30 days before and 30 days after EDIB, excluding the ED visit during which buprenorphine was given. Additionally, our electronic health information exchange, which includes all hospitals in our tri-county area, was also queried for ED visits in the same time period. The reason for ED visits was then classified as opioid-related (OR) or non-opioid related (NOR) based on the primary ICD-10 diagnosis code. OR diagnosis codes included polysubstance abuse, opioid use disorder, opioid dependence, heroin abuse, accidental drug overdose, withdrawal from opioids, opiate withdrawal, opioid withdrawal, opiate abuse, IV drug abuse, and drug addiction. The number of all-cause ED visits and OR ED visits was calculated both 30 days before and 30 days after EDBI. Additionally, nominal data collection occurred by assessing if each patient had at least 1 visit in the pre or post period for all-cause and opioid-related ED visits. McNemar’s exact test was used to compare groups. During the study period there were a total of 43 patients who underwent EDBI. 58% of patients were female, and the mean age was 33.4 years. Overall, 65% of patients were still in treatment at 30 days. The mean number of ED visits and opioid related ED visits decreased post-induction (0.35 ED visits/patient inducted to 0.14 and 0.21 ED visits/patient inducted to 0.02, respectively). There were 23 patients who did not have ED visits in either the 30-day pre or post EDBI period, 14 patients who only had ED visits in the pre period, 5 patients who only had visits in the post period, and 1 patient who had visits in both the pre and post periods for all-cause ED visits and 33,9,1 and 0 patients respectively for the OUD-related ED visits. An exact McNemar’s test determined that there was a statistically significant decrease in the proportion of patients utilizing the ED for opioid-related causes following EDIB (p=0.021) but no statistically significant difference for all cause ED visits (p=0.064). There was a significant reduction in the proportion of patients utilizing the ED for opioid-related visits for patients undergoing EDIB. There was also a reduction in the proportion of patients utilizing the ED for all-cause visits post EDBI, but the result was not statistically significant. This may be due to low power (N=43) and/or appropriate ED utilization for non-opioid related visits.