Characterization of drug-drug interactions in patients whose substance intake was objectively identified by detection in urine.

BACKGROUND: Identification of drug-drug interactions (DDIs) typically relies on patient medication lists which are prone to inaccuracies. This study describes use of a mass spectrometry test to detect recently ingested substances in urine with subsequent identification of DDIs. RESEARCH DESIGN AND METHODS: This was a retrospective analysis of the prevalence of DDIs identified in patients with chronic pain, addiction and/or behavioral health conditions in the U.S. Relationships between patient demographics, polypharmacy and the occurrence of DDIs were also described. RESULTS: Of 15,004 patients, 2964 (20%) had a DDI identified. There was a positive association between the number of substances detected in urine and the number of interactions identified (r = 0.5033, p-value = 0.0001). Of patients with polypharmacy, 15.6% had contraindicated or severe interactions identified compared to only 3.2% of those without polypharmacy. For polypharmacy patients, the youngest population studied had a much higher likelihood of having one or more DDIs identified compared to the other age groups (p-value = 0.0002). CONCLUSIONS: By utilizing a mass spectrometry test to objectively detect recently ingested substances followed by identification of DDIs, healthcare providers may be able to better characterize the true incidence of DDIs. Study findings may not be generalizable to healthcare populations outside of pain management, addiction treatment, and behavioral health.

Presence of Parent Cocaine in the Absence of Benzoylecgonine in Urine.

Cocaine (COC) is widely abused and associated with significant adverse effects. Forensic and clinical laboratories often test for COC intake through detection of the primary metabolite, benzoylecgonine (BZE) in urine. Testing for BZE alone may result in false-negative determinations in situations where COC is recently administered or metabolism is impaired. To our knowledge, no data have been provided demonstrating the utility of adding parent COC to urine confirmation testing in routine analyses. For this study, random urine specimens from patients undergoing treatment for pain management and/or addiction were collected over six months from 800 clinics across 39 states. A total of 7,587 urine specimens tested positive for a COC marker (COC and/or BZE). A positive result was determined using a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method with a limit of quantitation of 50 ng/mL. Of the positive specimens, 26% and 97% were positive for COC and BZE, respectively. Positive BZE-only specimens represented 74% of total positive specimens. However, 231 of the 7,587 urine specimens (3% of positive specimens) were positive for COC in the absence of BZE. The 231 COC-only positive specimens were collected from 206 patients, and two of these patients provided four COC-only positive specimens. Of a select group of COC-only specimens tested by both LC-MS-MS and immunoassay (IA) (N = 32), 81% were negative by IA, demonstrating the limitation of screening with BZE-specific IAs. A false-negative COC result can have profound impacts such as a delay in patient referral to addiction treatment, unintentional prescribing of a controlled substance to a patient actively abusing an illicit substance, or undetected cocaine use in the workplace. This study highlights the importance of testing for COC in addition to BZE in forensic and healthcare settings.

Urine drug testing results and paired oral fluid comparison from patients enrolled in long-term medication-assisted treatment in Tennessee.

Urine drug testing is recommended for individuals receiving medication-assisted treatment. It provides objective information for practitioners to consider and may serve as a protective factor against drug-related mortality. The primary objective of our study was to describe urine drug testing results for patients undergoing long-term medication-assisted treatment (≥6months). The secondary objective was to provide further evidence to establish oral fluid as a reliable alternative to urine. All subjects (n=639) included in the study were enrolled in one of five treatment centers in the state of Tennessee, and all urine specimens were positive for either methadone or buprenorphine. Nicotine (87%), caffeine (70%), marijuana (15%), alcohol (14%) and gabapentin (10%) were the most prevalent substances identified through urine drug testing. The presence of non-maintenance opioids (prescription and/or heroin) may represent relapse; these drugs were present in 10% of specimens tested. Evidence of illicit drug use (cocaine, heroin, marijuana and/or methamphetamine) was detected in 19% specimens. For 126 of the 639 subjects included in the study, paired oral fluid and urine test results were compared for agreement. Of the total paired urine and oral fluid tests, approximately 7% were positive for a drug in both specimen types and 91% were negative in both, resulting in an overall agreement of 98%. The study demonstrates continued use of illicit and commercially available medications in a medication-assisted treatment population undergoing long-term treatment. The results affirm the reliability of oral fluid as an alternative specimen type for compliance testing in this population.

Prevalence of heroin markers in urine for pain management patients.

Surveys of current trends indicate heroin abuse is associated with nonmedical use of pain relievers. Consequently, there is an interest in evaluating the presence of heroin-specific markers in chronic pain patients who are prescribed controlled substances. A total of 926,084 urine specimens from chronic pain patients were tested for heroin/diacetylmorphine (DAM), 6-acetylmorphine (6AM), 6-acetylcodeine (6AC), codeine (COD), and morphine (MOR). Heroin and markers were analyzed using liquid chromatography tandem mass spectrometry (LC-MS-MS). Opiates were analyzed following hydrolysis using LC-MS-MS. The prevalence of heroin use was 0.31%, as 2871 were positive for one or more heroin-specific markers including DAM, 6AM, or 6AC (a known contaminant of illicit heroin). Of these, 1884 were additionally tested for the following markers of illicit drug use: 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), methamphetamine (MAMP), 11-nor-9-carboxy-Δ(9)-tetracannabinol (THCCOOH), and benzoylecgonine (BZE); 654 (34.7%) had positive findings for one or more of these analytes. The overall prevalence of heroin markers were as follows: DAM 1203 (41.9%), 6AM 2570 (89.5%), 6AC 1082 (37.7%). MOR was present in 2194 (76.4%) and absent (

Urine drug testing of chronic pain patients. V. Prevalence of propoxyphene following its withdrawal from the United States market.

Propoxyphene is an opioid analgesic that was surrounded by controversy concerning its safety and efficacy during its lifespan in the US market. Propoxyphene was withdrawn in November of 2010 from the US market and is still being detected one year post-withdrawal in urine specimens from the pain management population. In this study, the prevalence of propoxyphene was determined in a total of 417,914 urine specimens collected from 630 clinics involved in pain management located in 24 states during the period of January 1, 2010, through December 31, 2011. Propoxyphene and norpropoxyphene were measured in urine by a validated liquid chromatography-tandem mass spectrometry procedure with a lower limit of quantitation of 50 ng/mL. The positivity rate for propoxyphene prevalence declined sharply between November and December of 2010 and further declined at a gradual rate, ending in a prevalence of 0.27% (one out of every 370 specimens, n = 25,658) for the month of December 2011. The presented data provide evidence of the dramatic decline in the use of propoxyphene products since their removal from the medical market, and may be beneficial to US urine drug testing programs determining the need for continual monitoring of propoxyphene levels.