Poster Number-55 - A Comparison of Definitive Urine Drug Test Results for Illicit Drugs in a Sample of People With Chronic Pain Prescribed Opioids to those Not Prescribed Opioids

A Comparison of Definitive Urine Drug Test Results for Illicit Drugs in a Sample of People With Chronic Pain Prescribed Opioids to those Not Prescribed Opioids 

Purpose:

Opioid prescribing has decreased dramatically over the past decade, and yet drug overdose deaths continue to climb.^1,2 Changing views about management of chronic pain with opioids have been reflected in shifting guidelines, policy and rules, and are driven by a desire to reckon with the societal problems of opioid misuse, addiction, diversion, overdose and death. In part, sparing people with chronic pain exposure to opioids is motivated by a desire to protect vulnerable people from the possibility of setting in motion misuse or unhealthy use of opioids and/or addiction. Whether these policies have been a success or failure is a matter of debate; in any event, the number of people with chronic pain treated with opioids has decreased to levels unseen since the early 1990s.¹

We set out to compare urine drug test (UDT) results from people with chronic pain not prescribed opioids to those prescribed opioids. We examined a large sample of people treated in pain management practices who underwent UDT with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology. We eliminated sub-groups of subjects who, it may be argued, might be best treated without opioids, while safer alternatives are trialed (e.g. patients with a history of substance use disorder), to drill down to the group in whom the reasons for foregoing opioids may be less obvious and more a reflection of present policy. Describing the influence of opioid prescribing on the frequency of UDT findings for illicit drugs may help those interested in understanding whether present policies are indeed protecting people with chronic pain from opioid misuse or whether it is resulting in dangerous self-treatment at a time when the drug supply of illicit and counterfeit opioids are tainted with lethal fentanyl, fentanyl analogues, and other excipients that can cause harm. People who think they are purchasing a legal opioid with which they are familiar from an illicit source might well be purchasing a lethal dose of fentanyl.

Methods:

This retrospective study of UDT results examined specimens obtained between January 1, 2019, - September 30, 2021, from patients receiving treatment in pain management practices. The study used a sample of 231,932 unique specimens, from Millennium Health’s proprietary UDT database. Specimens included in the study had been tested using LC-MS/MS for each analyte ordered based on clinician determination of medical necessity. The study protocol was approved by the Aspire Independent Review Board and includes a waiver of consent for the use of deidentified data. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.

We first determined those in the population who were reported to be prescribed opioids, using eight commonly prescribed opioids.  Out of the 231,932 total urine specimens, 170,992  (73.7%) were from patients who were prescribed at least one of the following drugs at the time of the sampling: fentanyl, codeine, hydrocodone, hydromorphone, oxymorphone, morphine, oxycodone, and tramadol.

We then evaluated positivity in the 231,932 specimens for four illicit substances; these were chosen because they are the four drugs known to contribute most to overdose deaths².  The following drugs and/or drug classes were tested based on the ordering clinician’s determination of medical necessity (drug and metabolites tested in parentheses): cocaine (benzoylecgonine), fentanyl (fentanyl, norfentanyl), heroin (6-monoacetylmorphine), and methamphetamine. If any parent analyte or metabolite was detected, the drug of interest was considered positive for that specimen. We excluded positive results for medications that contained these active ingredients that were reported by clinicians to be currently prescribed to patients (ie, if Desoxyn® was prescribed, we did not count them for methamphetamine positivity).

Additional characteristics for each specimen included the patient’s sex, age, diagnosis code, collection year and county of health care provider were also collected. The source of payment for the UDT was also included as a covariate in regression models.

We examined the crude prevalence of illicit drug positivity for the first collected specimen for each patient in each study year. Clopper-Pearson 95% binomial confidence intervals, Fisher’s exact test, and Poisson generalized estimating equations were used to further analyze the sample.

Results:

60,000 patients contributed the 231,932 total specimens, a mean of 3.9 specimens per patient. The population was mostly female (58.6%). The median patient age was 57 years old at collection and 58.3% were 55 years or older. The specimens were relatively evenly distributed for each collection year (31.0%-38.1%). 61.7% of patient specimens were collected in the East North Central, South Atlantic or Mountain divisions. 73.7% of patients were reported to be prescribed at least one of the eight opioids at the time of their first specimen, most commonly hydrocodone (31.5%) and oxycodone (32.5%).  ICD-10 diagnosis codes associated with Substance Use Disorders (SUD) were found in 11.4% of the patients.  A Fisher’s exact test demonstrated a significant negative association between SUD codes and opioid prescribing (OR=0.52[0.51-0.53], p< 2.2e-22) suggesting that opioid prescribing is reduced in the pain clinic population with an SUD diagnosis. Methadone (2.2%) and buprenorphine (7.5%) were found in the medication listings provided by the ordering physician. SUD diagnosis codes were positively associated with both methadone (OR=1.88[1.75-2.02], p< 2.2e-06) and buprenorphine (OR=3.39[3.27-3.51], p< 2.2e-06).

From 2019 to 2021, illicit positivity rates for heroin, fentanyl, cocaine and methamphetamine were lower in the population prescribed an opioid compared to those not prescribed an opioid. When patients with SUD and patients prescribed buprenorphine or methadone were removed from the analysis, those prescribed an opioid were 47% less likely to be positive for illicit fentanyl, 52% less likely to be positive for heroin, 63% less likely to be positive for methamphetamine, and 32% less likely to be positive for cocaine (all significant at p< 0.001).

Conclusion:

The results of this study suggest that people with chronic pain who are not prescribed opioid medications are more likely to have UDT results positive for illicit drugs, than were those prescribed opioid medications. It is unclear what the actual clinical circumstances and motives of people with pain who use illegally obtained drugs are from a database such as this one. Is their use of these drugs the result of desperation to relieve pain and other symptoms?  Or is their unsanctioned use a manifestation of a substance use disorder? Based on our analysis, avoiding opioid prescribing does not automatically translate to less drug use on the part of people with chronic pain – at a time when self-medication using street opioids has perhaps never been more dangerous. Instead, safe opioid prescribing processes might be preferred wherein the hope would be that adequate comfort and pain management with needed safeguards might help a subset of people with chronic pain avoid desperate and dangerous attempts to self-treat.

References: 1. American Medical Association. 2021 Overdose Epidemic Report: Physicians’ actions to help end the nation’s drug-related overdose and death epidemic —and what still needs to be done. Available at: https://www.ama-assn.org/system/files/ama-overdose-epidemic-report.pdf. Accessed July 2022.
2. Provisional Drug Overdose Death Counts. National Center for Health Statistics. Centers for Disease Control and Prevention Website. https://www.cdc.gov/nchs/nvss/vsrr/drug-overdose-data.htm. Accessed November 2021.