Unrelieved pain and risk of opioid use disorder or overdose in older adults prescribed opioids

It is unclear to what extent unrelieved pain, the most common motive for prescription opioid misuse, is associated with risks of opioid use disorder (OUD) and opioid overdose (OD) among older adults with prescribed opioids. This retrospective cohort study was conducted among Health and Retirement Study (HRS) participants with linked Medicare claims data between 2006 and 2021. Participants aged 65 years or older with chronic pain who had received at least 1 opioid prescription entered the cohort in an HRS-assessed pain assessment (index) between 2008 and 2020. We included 2 time-varying measures of HRS-assessed pain exposure: uncontrolled pain, defined as having moderate or severe pain, and high-impact pain, defined as having moderate to severe pain that impacted daily activities. Primary outcomes of incident OUD or OD diagnosis were analyzed using separate Cox regression models with marginal structural modeling. Of 3104 eligible participants identified, 1359 (43.8%) had uncontrolled pain and 1044 (33.6%) experienced high-impact pain in the index wave. In the marginal structural modeling-adjusted Cox regression model, patients with uncontrolled (vs controlled) pain had higher risks of OUD (adjusted hazard ratio [AHR] 9.70; 95% confidence interval [CI], 4.56-20.63) and OD (AHR 2.46; 95% CI 1.30-4.66). The AHR for OUD was 6.74 (95% CI 3.76-12.08) and for OD was 1.96 (95% CI 1.07-3.60) times higher for patients with vs without high-impact pain. Our findings underscore the importance of regular assessment and modification of pain management for older patients whose pain remains unrelieved after opioid treatment, to lower the risk of OUD and OD.