Purpose: Despite the rise in opioid-related hospitalizations, there has been little research regarding opioid-related healthcare utilization. The objective of this study was to estimate the mean adjusted hospital costs, payments, and length of stay (LOS) for opioid-related visits for the nation and each of the nine US census regions.
Methods: An observational study of retrospective claims data from the Vizient health system database was conducted. Eligible visits had a principal diagnosis of opioid use or dependence defined by ICD, ninth and tenth revision (ICD-9/10), and occurred between January 2014 and June 2017. Separate regression models for inpatient and outpatient visits were generated to estimate the adjusted costs, payments, and LOS for opioid-related visits.
Results: A total of 193,614 (32,713 inpatient and 160,901 outpatient) visits met the inclusion criteria. The overall adjusted mean cost, payment, and LOS for an inpatient opioid-related visit were $4,383 (range between regions: $2,894–$5,835), $6,689 (range between regions: $4,038–$9,001), and 4.35 days (range between regions: 3.8–5.7 days), respectively. The overall adjusted mean cost and payment for an outpatient opioid-related visit were $533 (range between regions: $395–$802) and $374 (range between regions: $187–$574), respectively. Opioid-related hospital costs, payments, and LOS varied across the US. Data on the regional variation and national averages are necessary for hospitals to benchmark their services and more effectively manage this population. 
Conclusion: Future research should examine intraregion utilization to understand the effect of prices and level of services.
Keywords: opioid use disorder, healthcare utilization, geographic variation, administrative claims