Chronic pain among patients with opioid use disorder: Results from electronic health records data.

Opioid use disorder (OUD) is associated with excess mortality, morbidities, and other adverse health and social conditions. OUD is common among individuals with chronic pain conditions, and chronic pain is common among individuals with OUD. The relationship between chronic pain and OUD and the time course of the two is complex and other physical and mental health problems often co-occur with them both as well. The goal of this study was to examine chronic pain among patients with OUD, as well as to examine other substance use disorders, health, mental health, and treatment for health and mental health among patients in medical settings using electronic health records (EHRs).

Using an EHR database from 2006-2015, the study assessed 5307 adult patients with OUD in a large healthcare system (University of California, Los Angeles, CTN Pacific Region Node), separating them into four categories: no chronic pain (No Pain, 35.6%), OUD prior to pain (OUD First, 9.7%), OUD and pain at the same time (Same Time, 14.9%), and pain condition prior to OUD (Pain First, 39.8%).

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% 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 (28.2%) among the four groups. Pain First patients had the highest rates of mental disorder (81.7%), heart disease (72%), 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.