Long-term naturalistic follow-up of chronic pain in adults with prescription opioid use disorder.

BACKGROUND:Chronic pain is common in patients with prescription opioid use disorder (OUD), and pain severity has been shown to predict opioid use for those with chronic pain. However, recent research suggests that focusing on pain status (i.e., the presence or absence of chronic pain) at treatment initiation may not reflect the clinical significance of pain over the long-term course of OUD. Reports of variability in chronic pain and its clinical significance over time have yet to be investigated in patients with prescription OUD. The present study examined variability in chronic pain status from entry into prescription OUD treatment through 3.5-year follow-up. Additionally, we examined the association between concurrent chronic pain and opioid use at three follow-up time points. METHODS:This secondary analysis (N = 309) of a national, randomized, controlled trial of prescription OUD treatment used generalized estimating equations to assess variability in the prevalence of chronic pain from study entry to 3.5-year follow-up, and the association between chronic pain status and concurrent opioid use. RESULTS:Fifty-three percent of participants reported variability in chronic pain status over time. The prevalence of chronic pain decreased from study entry through follow-up (aOR = 0.47, p < 0.001). Chronic pain was associated with increased opioid use at each follow-up assessment (aOR = 3.56, p < 0.001). CONCLUSIONS:Chronic pain status may vary over time in those with prescription OUD, and chronic pain appears to be associated with concurrent opioid use. The present findings highlight the importance of assessing chronic pain throughout the course of prescription OUD.