Opioid Use Disorder: A Qualitative Exploratory Analysis of Potential Misunderstandings in Patients with Chronic Non-Cancer Pain

Purpose: Substance use disorders (SUD) are a challenging comorbidity in patients with chronic non-cancer pain (CNCP) as they complicate diagnosis and therapy, especially when opioids are part of the therapeutic regimen. A definite diagnosis of opioid use disorder (OUD) in patients with CNCP on long-term opioid therapy (LTOT) is a prerequisite for effective and targeted therapy but may be complicated as some criteria of OUD might be attributed to the desire of the patient to relieve the pain. For instance, the desire to increase the dose can be based on both a SUD as well as inadequate pain therapy. Many scientific studies use standardized questions. Therefore, potential misunderstandings due to possible diagnostic overlaps often cannot be clarified. Methods: 14 qualitative guided interviews were conducted and analyzed (Kuckartz content analysis), with the intention to verify if patient's initial response to simple questions based on the wording of the DSM-5, as commonly used in research and practice, were consistent with the results of a more in-depth inquiry. Results: The results suggest that without in-depth investigation, there is a particular risk of false-positive assessment of the DSM-5 criteria for OUD when opioids are prescribed, especially when the questions are considered independently of chronic pain. The risk of a false-negative assessment has also been shown in isolated cases. Conclusion: Only after asking for and describing specific situations it was possible to determine whether the patient's positive or negative answers were based on a misunderstanding of the question. To avoid misdiagnosis, staff conducting DSM-5 interviews should be trained in pain-specific follow-up questions that may help to uncover diagnostic confounding.