What Urine Drug Tests Reveal During Opioid Therapy for Chronic Pain: A Study Summary
Urine drug testing (UDT) is a common safety step for patients who take opioids for chronic pain. It can show whether a prescribed medicine is present and whether other substances are present. But how often do results raise real concern? A study in the Journal of General Internal Medicine looked at this question.
This summary is based on the published abstract; the full paper may include additional detail. Read the abstract on PubMed: https://pubmed.ncbi.nlm.nih.gov/34405344/
What was studied
UDT is recommended as a way to lower risk during opioid therapy, but the authors note that evidence that it helps identify substance misuse is limited. They set out to measure how often UDT results might point to misuse, including diversion (a prescribed medicine not being taken by the patient).
How it was done
This was a retrospective cohort study of 638 patients receiving opioids for chronic pain who had at least one UDT over one year. Each sample was checked for up to eight substances. Experts then reviewed the results and rated each one as not concerning, uncertain, or concerning.
About half of the patients were women, and about half were over age 55. Patients had a median of three tests during the year.
Key findings
- Concerning results were common. 37% of patients had at least one concerning result. Another 35% had at least one uncertain result.
- Two main patterns. 24% of patients had a concerning result because a prescribed medicine was not detected. 23% had a concerning result because a non-prescribed substance was detected.
- Who was more likely to have a concerning result: patients aged 18 to 34, compared with those over 65 (adjusted odds ratio 4.8); patients with a mental health diagnosis (adjusted odds ratio 1.6); and patients with a substance use diagnosis (adjusted odds ratio 2.3).
Limitations
- The study was retrospective and looked back at existing records.
- Concern was judged by expert review, not by confirmed outcomes.
- The study did not show whether testing changed care or improved patient outcomes. The authors call for more research on this.
Safety takeaways
- Unexpected results are not rare. Clinicians who prescribe long-term opioids should expect some results that need follow-up.
- A missing prescribed medicine is a red flag worth discussing. It may have several explanations, and a calm, direct conversation is the first step.
- A non-prescribed substance changes the risk picture. Combining opioids with other substances can raise the risk of serious harm.
- Context matters. Younger age and mental health or substance use diagnoses were linked to concerning results, so these patients may benefit from closer support.
- Interpret, don't just test. Results should be reviewed carefully, confirmed when needed, and discussed openly with the patient.
- Document the plan. Recording results, the conversation, and next steps supports safe, consistent care.
Reference
- Larochelle MR, Cruz R, Kosakowski S, Gourlay DL, Alford DP, Xuan Z, et al. Do Urine Drug Tests Reveal Substance Misuse Among Patients Prescribed Opioids for Chronic Pain? J Gen Intern Med. 2022;37(10):2365-2372. DOI: 10.1007/s11606-021-07095-8. PMID: 34405344. Abstract: https://pubmed.ncbi.nlm.nih.gov/34405344/
Related: Opioid Prescribing Cases
This article is educational information, not legal or medical advice.
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