Chronic Pain Reported in Nearly Half of Recipients of Opioid Substitution Treatment

Authors of a systematic review and meta-analysis published in The Journal of Pain reported that nearly half of patients receiving opioid substitution treatment for opioid use disorder (OUD) have chronic pain.

Investigators from Université Clermont Auvergne in France searched publication databases for studies about the prevalence of chronic pain among patients receiving opioid substitution treatment for OUD published between 2000 and 2020.

A total of 23 cross-sectional studies were included in this analysis. The studies were conducted in the United States (n=15), Israel (n=4), France (n=2), the United Kingdom (n=1), and Australia (n=1) in the setting of primary care (n=9), specialty care (n=9), both primary and specialty care (n=3), and national healthcare databases (n=2).

The mean age of the patients recruited to participate in these studies was 40.2 (range, 26.9-45.9) years, and on average 62.6% of the patients were men. Two studies recruited specialty populations of people living with HIV and women with a history of sexual abuse. The opioid substitution treatment regimens included methadone (n=16), methadone or buprenorphine (n=5), and buprenorphine (n=2), and duration of treatment was at least 6 months (n=11), at least 3 months (n=10), and at least 12 months (n=2).

In the meta-analysis, the overall prevalence of chronic pain among recipients of opioid substitution treatment for OUD was 45.3% (95% CI, 38.7%-52.1%; I², 99.8%). Stratified by individual studies, the proportion of patients with chronic pain ranged from 12.7% to 67.6%.

In studies conducted in medical clinics, the proportion of patients with chronic pain was 54.6% (95% CI, 47.4%-61.8%; I², 90.6%) and ranged from 35.9% to 67.6% in individual studies. In the primary care setting, the overall proportion of patients with chronic pain was 46.8% (95% CI, 40.4%-53.3%; I², 84.0%) and ranged from 36.1% to 63.2%.

In a sensitivity analysis that excluded 2 studies because they represented 94.9% of the total study population, the prevalence of chronic pain among patients receiving opioid substitution treatment for OUD was 48.9% (95% CI, 44.2%-53.7%; I², 94.6%) and ranged from 33.0% to 67.6%.

A major limitation of this study was the substantial and significant heterogeneity observed in all analyses.

These data indicate that chronic pain is common among patients receiving opioid substitution treatment for OUD. The study authors conclude, “Thus, the urgent challenge in [opioid substitution treatment] patients is to pay systematic attention to [chronic pain] diagnosis, along with the implementation of a multidisciplinary patient-focused approach for an appropriate management of [chronic pain].”