Association of Opioid Use Disorder Diagnosis with Management of Acute Low Back Pain: A Medicare Retrospective Cohort Analysis

Abstract

Background: Practice guidelines recommend nonpharmacologic and nonopioid therapies as first-line pain treatment for acute pain. However, little is known about their utilization generally and among individuals with opioid use disorder (OUD) for whom opioid and other pharmacologic therapies carry greater risk of harm.

Objective: To determine the association between a pre-existing OUD diagnosis and treatment of acute low back pain (aLBP).

Design: Retrospective cohort study using 2016-2019 Medicare data.

Participants: Fee-for-service Medicare beneficiaries with a new episode of aLBP.

Main measures: The main independent variable was OUD diagnosis measured prior to the first LBP claim (i.e., index date). Using multivariable logistic regressions, we assessed the following outcomes measured within 30 days of the index date: (1) nonpharmacologic therapies (physical therapy and/or chiropractic care), and (2) prescription opioids. Among opioid recipients, we further assessed opioid dose and co-prescription of gabapentin. Analyses were conducted overall and stratified by receipt of physical therapy, chiropractic care, opioid fills, or gabapentin fills during the 6 months before the index date.

Key results: We identified 1,263,188 beneficiaries with aLBP, of whom 3.0% had OUD. Two-thirds (65.8%) did not receive pain treatments of interest at baseline. Overall, nonpharmacologic therapy receipt was less prevalent and opioid and nonopioid pharmacologic therapies were more common among beneficiaries with OUD than those without OUD. Beneficiaries with OUD had lower odds of receiving nonpharmacologic therapies (aOR = 0.62, 99%CI = 0.58-0.65) and higher odds of prescription opioid receipt (aOR = 2.24, 99%CI = 2.17-2.32). OUD also was significantly associated with increased odds of opioid doses ≥ 90 morphine milligram equivalents/day (aOR = 2.43, 99%CI = 2.30-2.56) and co-prescription of gabapentin (aOR = 1.15, 99%CI = 1.09-1.22). Similar associations were observed in stratified groups though magnitudes differed.

Conclusions: Medicare beneficiaries with aLBP and OUD underutilized nonpharmacologic pain therapies and commonly received opioids at high doses and with gabapentin. Complementing the promulgation of practice guidelines with implementation science could improve the uptake of evidence-based nonpharmacologic therapies for aLBP.

Keywords: Medicare.; acute pain; chiropractic; gabapentin; opioid prescribing; physical therapy.