1148 — Identifying predictors of pain intensity following discontinuation of long-term opioid therapy among patients with and without substance use disorders

Lead/Presenter: Travis Lovejoy,  COIN - Portland
All Authors: Lovejoy TI (Center to Improve Veteran Involvement in Care, VA Portland Health Care System), Smith CL (Washington State University, School of Medicine), Morasco BJ (Center to Improve Veteran Involvement in Care, VA Portland Health Care System) Dobscha SK (Center to Improve Veteran Involvement in Care, VA Portland Health Care System) Holloway J (Center to Improve Veteran Involvement in Care, VA Portland Health Care System) McPherson S (Washington State University, School of Medicine)

Objectives:
Recent empirical findings indicate that among chronic pain patients with and without substance use disorders (SUDs), pain intensity does not change on average following discontinuation of long-term opioid therapy (LTOT). Furthermore, patients fall into one of four discrete groups characterized by no, mild, moderate, or severe pain intensity in the year following opioid discontinuation. The objective of this study was to characterize differences between patients with different levels of pain following discontinuation of LTOT.

Methods:
Retrospective electronic health record data were obtained from a national sample of N = 600 U.S. Department of Veterans Affairs (VA) patients who discontinued LTOT in 2012. Data included demographic and clinical characteristics of the sample, and pain intensity ratings (using a 0-10 numeric rating scale) obtained during routine outpatient clinical encounters in the year preceding and following opioid discontinuation.

Results:
Growth mixture models identified four groups of pain intensity trajectories: subclinical pain (30% of the sample; average pain at discontinuation = 0.05), mild clinically-significant pain (17%; average pain = 3.59), moderate clinically-significant pain (27%; average pain = 5.97), and severe clinically-significant pain (26%; average pain = 7.83). Pain trajectories in each of the four groups were characterized by statistically significant, but non-clinically meaningful, reductions in pain over time. Ordinal logistic regression analyses demonstrated that variables significantly associated with a greater likelihood of higher pain intensity group membership were having an alcohol or other SUD, excluding nicotine (OR = 1.38, 95% CI = 1.00-1.92), higher average pain intensity prior to discontinuation (OR = 1.27, 95% CI = 1.19-1.37), and being discontinued from LTOT by a treating clinician versus discontinuing of one's own volition (OR = 1.64, 95% CI = 1.05-2.56).

Implications:
Patients with co-occurring SUD, higher pain intensity, and those forced to discontinue LTOT by treating clinicians were more likely to experience higher and persistent pain following discontinuation of LTOT.

Impacts:
Overall opioid prescribing across the U.S. and in VA has declined year-over-year since 2012, yet mortality rates due to opioid overdose continued to rise. This study's findings point toward groups of patients that may be targeted for additional integrated pain treatment options during and after prescription opioid discontinuation to prevent possible transitions to high-risk illicit use of heroin and fentanyl.