UCLA

Purpose

To examine the prevalence of comorbid chronic pain among patients with opioid use disorder (OUD) and to compare other comorbidities (substance use disorder (SUD), mental health disorders, health/disease conditions) among patients in four categories: no chronic pain (No Pain), OUD prior to pain (OUD First), OUD and pain at the same time (Same Time), or pain condition prior to OUD (Pain First).

Methods

Using an electronic health record (EHR) database from 2006-2015, the study assessed 5307 adult patients with OUD in a large healthcare system; 35.6% were No Pain, 9.7% were OUD First, 14.9% were Same Time, and 39.8% were Pain First.

Results

Most OUD patients (64.4%) had chronic pain conditions, and among them 61.8% had chronic pain before their first OUD diagnosis. Other SUDs occurred more frequently among OUD First patients than among other groups in terms of alcohol (33.4% vs. 25.4% for No Pain, 20.7% for Same Time, and 20.3% for Pain First), cocaine (19.0%, vs. 13.8%, 9.4%, 7.1%), and alcohol or drug-induced disorders. OUD First patients also had the highest rates of HIV (4.7%) and hepatitis C virus (HCV; 28.2%) among the four groups. Pain First patients had the highest rates of mental disorder (81.7%), heart disease (72.0%), respiratory disease (68.4%), sleep disorder (41.8%), cancer (23.4%), and diabetes (19.3%).

Conclusions

The alarming high rates of chronic pain conditions occurring before OUD and the associated severe mental health and physical health conditions require better models of assessment and coordinated care plans to address these complex medical conditions.