Prescription Opioids, Brain Structure, and Cognition in Older Adults With Chronic Pain

The purpose of this study is to determine whether exposure to prescription opioids is associated with brain structural changes on magnetic resonance imaging (MRI), with the primary outcome of white matter integrity as measured by fractional anisotropy of the corpus callosum.

The investigators will recruit 200 adults aged 65 years and older with chronic pain of the knee or shoulder. Each will receive an individualized multimodal pain treatment pathway for 6-weeks - for half of participants this will include a prescription opioid; the other half will receive an identical placebo. After 6 weeks, participants will undergo opioid/placebo taper. The investigators will obtain neuroimaging (MRI), psychometric/cognitive testing, pain scores, and several exploratory patient-reported outcomes at several time-points: before the intervention (all tests), at 6 weeks (all tests except MRI), 6-month phone call (only phone based patient reported outcomes- no MRI), and at 1 year (all tests).