In 1986, President Ronald Reagan issued Executive Order 12564, which mandated a drug-free federal workplace. The concept was not new. The Department of Defense had established a program for detecting and punishing drug use among military personnel nearly 20 years earlier, during the Nixon administration. Reagan’s initiative expanded surveillance to all federal employees, and eventually to anyone working in a job that is regulated by a federal agency. Many state governments and private employers followed suit with their own drug-free workplace programs, and within a few years workplace drug testing grew into the enormous industry it is today. Analytical specifications for urine drug testing (UDT) were codified in federal law, and laboratories meeting those specifications were eligible for certification and regulation by federal agencies. Most state and private drug testing programs adopted the federal standards. In these drug testing programs, use of drugs could constitute a criminal offense, so the specifications for UDT were designed to meet the evidentiary standards of criminal law.
Over the past decade UDT has increasingly been applied under very different scenarios: monitoring compliance with prescribed use of opioids for management of pain, and surveillance of patients enrolled in substance abuse recovery programs. In these settings, the aim of UDT is distinctly different from ensuring a drug free workplace or penalizing illegal drug use, yet the same analytical standards often are applied. For example, a negative result on a urinary opiate screen that meets the standard for workplace drug testing does not necessarily rule out compliant use of an opioid (for which the assay may have limited sensitivity) by a patient under legitimate medical treatment. Likewise, methods designed to detect ethanol intoxication (blood or breath ethanol) are mostly inadequate for determining whether a patient has remained abstinent, and detecting ethanol metabolites in the urine of a patient required to be abstinent may not reflect intentional use, but rather innocent exposure to ethanol-containing products, such as the ubiquitous hand sanitizers health care workers (and just about everyone else) are encouraged to use.
(Reminded of this, I just noticed the dispenser of hand sanitizer on my desk and robotically cleansed my hands for the third of fourth time today.)
Increasingly, UDT is being used for purposes it was not designed to meet, and with analytical specifications that may not be pertinent to the clinical questions being asked. Clinicians want to know whether their patients are responsibly adhering to prescribed opioid therapy or diverting the medication for profit. Clinicians want to know whether their patients are abstinent from drug use, or have violated the terms of their treatment plan. There is currently a demand for UDT in support of pain management and substance abuse recovery programs, and laboratories have responded with services ostensibly tailored to that demand.
That’s a good thing. Clinical laboratories are, after all, in the business of providing economical and worthwhile services that meet the needs of healthcare providers in every clinical setting.
But here’s the point: the use of UDT in pain management, or in substance abuse monitoring programs, has not been validated to the degree we ordinarily require of analytical methods used for clinical decision making. In some respects, these are “off label” applications of UDT. For example, what concentration of urinary opioids or their metabolites is sufficient to verify adherence to prescribed opioid therapy? What concentration of urinary ethanol metabolites confirms the use of alcoholic beverages? Does the presence of multiple metabolites in the urine reflect the use of more than one drug, or minor pathways for metabolism of a single drug? These are important questions, and data on which to base their answers are scarce. Drug testing services for pain management or substance abuse recovery programs are a large and growing industry that offers many incentives for clinical laboratories to enter that arena (not the least of which is virtually guaranteed reimbursement). However, laboratories should exercise caution in how these services are marketed, aware of the fact that UDT was developed for a different purpose, and its application to pain management and substance abuse recovery programs involves limitations that clinicians rarely understand.