1. 2011;14;189-193Illicit Drug Use in the Pain Patient Population Decreases with Continued Drug Testing
   Retrospective Study
   Amadeo Pesce, PhD, Cameron West, PhD, Murray Rosenthal, DO, Charles Mikel, PhD, Robert West, MS, Bridgit Crews, PhD, Perla Almazan, MT, Sergey Latyshev, MS, and Paul S. Horn, PhD.

BACKGROUND: A major concern of physicians treating pain patients with chronic opioid therapy and similar drugs is determining whether the patients are also using illicit drugs. This is commonly determined by urine drug testing (UDT). However, there are few studies on whether or not monitoring patients by this technique decreases illicit drug use.

OBJECTIVE: To determine if the presence of illicit drugs decreases over a number of physician visits where UDT was performed.

METHOD: The method involved a retrospective study of tests for the illicit drugs marijuana, cocaine, methamphetamine, ecstacy (MDMA) phencyclidine (PCP) and the heroin metabolite, 6-acetylmorphine as confirmed by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). A database of 150,000 patient visits was examined for the presence of any of these 6 drugs.

RESULTS: A total of 87,000 patients were initially tested. The number of patients who were repeatedly tested decreased over time. The percentage of patients positive for any of these illicit drugs decreased from 23% to 9% after 14 visits where UDT was performed. When graphed there was a trend to decreasing use. The Spearman correlation = -0.88, p < 0.0001. The major illicit drug was marijuana. When this was removed from the analysis, there was an even greater correlation with decreased illicit drug use. Spearman correlation = -0.92 (p < 0.0001) using a weighted correlation.

LIMITATION: Patients continuing to use illicit drugs might be dismissed from practices thus biasing the study towards illicit drug avoidance.

CONCLUSION: Continued UDT might decrease illicit drug use among pain patients.