CONCLUSION
Pain and OUD are complex clinical conditions with consequences that go beyond the biomedical into psychological and societal realms. When combined, the challenge of assessing and properly addressing pain in persons with OUD is magnified, as their pathophysiology, signs, and symptoms overlap and modify each other. In this review, we discussed how pain is a multidimensional biopsychosocial entity, adding nuance to the clinical presentation of OUD. Opioids are capable of modulating pain but can also produce phenomena that challenge their assessment such as hyperalgesia, tolerance, and withdrawal symptoms. For a substantial proportion of individuals with OUD, pain and opioid use become inexorably connected, thus, clinical, and experimental assessments of pain deserve special considerations. Pain inventories, scales, behavioral and physiological findings, as well as technology-based assessments have to be considered carefully, as opioid use and its phenomena reshape traditional assessment of pain in patients without OUD.
Unfortunately, research considering how pain and OUD are interconnected and how these assessments can be clinically used remains relatively undeveloped. For many of the pain assessment methods discussed in this review, there are few clinical trials exploring their applications for persons with OUD. Furthermore, an upstream deficit exists in medical education and multidisciplinary clinical approaches for the co-management of pain and addiction, with very few programs in the country discussing these combined issues. The ongoing opioid crisis demands more than passive acknowledgment; it calls for proactive, informed action. Beyond serving as a review of the available literature on the topic, we present this paper as a call-to-action, as the gaps in knowledge regarding pain assessment in patients with OUD are alarming. As research linking these two areas evolves, considering the needs of diverse populations with complex psychosocial backgrounds, and understanding the role that such psychosocial variables may play in the worsening of pain and OUD, we will be better equipped to reduce these gaps. Given the profound overlap between chronic pain and OUD—and the fact that the opioid epidemic’s initial surge is closely tied to inadequate treatment of chronic pain—it becomes clear: our united commitment is essential. Together, pain and addiction clinicians and scientists must strive to improve the assessment of pain in persons with OUD, an important step to curtail the spiraling opioid crisis.
TABLE 1. Methods of pain assessment and considerations in patients with opioid use disorder: an overview.