A Descriptive analysis of urine drug screen results in patients with opioid use disorder managed in a primary care setting.

BACKGROUND: Urine drug screening (UDS) is commonly used as part of treatment for opioid use disorder (OUD), including treatment with buprenorphine-naloxone for OUD in a primary care setting. Very little is known about the value of UDS, the optimum screening frequency in general, or its specific use for buprenorphine treatment in primary care. To address this question, we thought that in a stable population receiving buprenorphine-naloxone in the primary care setting it would be useful to know how often UDS yielded expected and unexpected results. METHODS: We present a descriptive analysis of UDS results in patients treated with buprenorphine-naloxone for OUD in a primary care setting over a two-year period. An unexpected test result is: 1. A negative test for buprenorphine and/or 2. A positive test for opioids, methadone, cocaine and/or heroin. RESULTS: A total of 161 patients received care during the study period and a total of 2588 test results were analyzed from this population. We found that 64.4% of the patient population (n = 104 patients) demonstrated both treatment adherence (as measured by buprenorphine positive test results) and no apparent unexpected test findings, as defined by negative tests for opioids, methadone, cocaine and heroin. Of the 161 patients, 20 results were positive for opioids, 5 for methadone, 39 for heroin and 2 for cocaine. Analysis at the UDS level demonstrated that, of the 2588 test results, 38 (1.5%) results did not have buprenorphine. Of the 2588, 28 (1.1%) test results were positive for opioids, 8 (0.3%) were positive for methadone, 39 (1.5%) for cocaine and 2 (0.1%) for heroin. CONCLUSION: Given that the majority of patients in our study had expected urine results, it may be reasonable for less frequent urine testing in certain patients.

Urinary Buprenorphine, Norbuprenorphine and Naloxone Concentrations and Ratios: Review and Potential Clinical Implications.

OBJECTIVES: Treatment with medications for opioid use disorder such as buprenorphine improves patient morbidity and mortality as well as treatment adherence, an important component of patient care. Buprenorphine is combined with naloxone to reduce misuse; and, when taken sublingually, naloxone is poorly absorbed. Urine testing for buprenorphine is a common way to monitor adherence. Some patients who want to appear adherent may directly tamper with their urine by adding buprenorphine to their urine to allow for the detection without ingestion. Practitioners may rely upon the concentration of buprenorphine and the metabolite, norbuprenorphine, and utilize the ratio of metabolite to parent compound (norbuprenorphine:buprenorphine - N:B ratio) to discern possible evidence of tampering; however, there remains debate as to what specific ratio may signify this practice. Testing for naloxone may also help determine if urine tampering occurred as only low naloxone concentrations are found in the urine when taken by a sublingual route. METHODS: To determine a reliable N:B ratio that may be used to identify possible urine tampering by adding parent drug directly to urine, we examined 136,605 urine samples for quantitative concentrations of buprenorphine and norbuprenorphine by LC-MS/MS performed at a commercial laboratory. After identifying abnormal ratios (<0.02), we then compared them with naloxone concentrations and specimen validity testing, other markers that may coincide with specimen tampering of this type. RESULTS: Correlating urinary buprenorphine and norbuprenorphine concentrations, we found 2 distinct patient populations, which could be distinguished by N:B ratios ranging from 0.01 to 0.2. In addition, while the distribution of urine naloxone concentrations itself did not demonstrate distinct populations, naloxone was able to further flag potential tampered specimens when combined with N:B ratios. Abnormal specimen validity testing was additionally found more commonly in cases with N:B ratios <0.02. CONCLUSIONS: This comprehensive study compared N:B ratios with naloxone concentrations and specimen validity testing. This study suggests that a N:B ratio of <0.02 in concert with high naloxone concentrations (>1000 ng/ml) can help to identify potential cases of tampered urine samples.

Use of urinary naloxone levels in a single provider practice: a case study.

BACKGROUND: Urine drug monitoring for medications for opioid use disorder (MOUD) such as buprenorphine can help to support treatment adherence. The practice of introducing unconsumed medication directly into urine (known as "spiking" samples) has been increasingly recognized as a potential means to simulate treatment adherence. In the laboratory, examination of the ratios of buprenorphine and its metabolite, norbuprenorphine, has been identified as a mechanism to identify "spiked" samples. Urine levels of naloxone may also be a novel marker in cases where the combination buprenorphine-naloxone product has been administered. This case study, which encompasses one provider's practice spanning two sites, represents a preliminary report on the utility of using urinary naloxone as an indicator of "spiked" urine toxicology samples. Though only a case study, this represents the largest published evaluation of patients' naloxone levels to date. CASE PRESENTATION: Over a 3-month period across two practice sites, we identified 1,223 patient samples with recorded naloxone levels, spanning a range of 0 to 12,161 ng/ml. The average naloxone level was 633.65 ng/ml with the majority (54%) of samples < 300 ng/ml. 8.0% of samples demonstrated extreme values of naloxone (> 2000 ng/ml). One practice site, which had increased evidence of specimen tampering at collections, had a greater percent of extreme naloxone levels (>  2000 ng/ml) at 9.3% and higher average naloxone level (686.8 ng/ml), in contrast to a second site (570.9 ng/ml; 6.4% at > 2000 ng/ml) that did not have known reports of specimen tampering. CONCLUSIONS: We postulate that naloxone may serve as an additional flag to identify patient "spiking" of urine samples with use of the combination product of buprenorphine-naloxone.

Driving Access to Care: Use of Mobile Units for Urine Specimen Collection During the Coronavirus Disease-19 (COVID-19) Pandemic.

Patients with substance use disorders (SUD) are at increased risk of both coronavirus disease-19 complications as well as exacerbations of their current conditions due to social distancing and isolation. Innovations that provide increased access to support substance use disorder patients may mitigate long-term sequelae associated with continued or renewed drug use. To improve patient access during the coronavirus disease-19 pandemic, we deployed a mobile unit to enable access to urine drug testing where needed for patients suffering from substance use disorder. Over a 3-week pilot program, 54 patients received urine drug testing across 5 providers and 8 zip codes. The mobile unit was cost-effective, demonstrating a volume-dependent 19% lower cost compared to pre-coronavirus disease-19 patient service centers in a similar geographic region. The mobile unit was well-received by patients and providers with an average of 9 out of 10 satisfaction scores and allowed for access to urine drug testing for 67% patients who would not have received testing during this time frame. No statistically significant differences were found in substance use positivity rates in comparison to pre-coronavirus disease findings; however, some shifts in use included higher rates of fentanyl and opioid positivity and reductions in tetrahydrocannabinol and cocaine use in the mobile collections setting. Deployment of mobile collection services during the coronavirus disease-19 pandemic has shown to be an effective mechanism for supporting patients suffering from substance use disorder, allowing for access to care of this often stigmatized, vulnerable population.