The number of people combining toxic drugs is more than most physicians realize, according to a recent study comparing laboratory data to patient-reported data. Quest Diagnostics looked at de-identified clinical laboratory data from patients prescribed at least one drug and whose physicians requested drug monitoring. The study used population health data from patients in 48 states, with the findings divided into several data groups including gender, age, geographic location and type of payer.
The concurrent use of opioids and benzodiazepine drugs, with one being prescribed and one not being prescribed, often signals potentially lethal drug use without clinical oversight, according to the study published in the September 2017 Journal of Addiction Medicine. The study used laboratory data collected from nearly 150,000 Quest Diagnostics patients over a 10-month span. Authors say the study is one of the first to use clinical laboratory data to discover potential drugs abuse instead of using prescription data.
The study found that 25% of patients monitored for drug use used both opioids and benzodiazepines at the same time. For 52% of those patients using both drugs, one of the drugs being used was not prescribed. Of those found using both drugs, nearly 20% of those prescribed to use opioids were also using non-prescribed benzodiazepines, and more than 15% of those prescribed to use benzodiazepines were using non-prescribed opioids.
Concurrent drug use of opioids and benzodiazepines was found in 11.2% of all test results, though only 9.6% of patients reported being prescribed both drugs. Stefan Kertesz, MD, an addiction medicine specialist at University of Alabama, says that urine drug tests can frequently diverge from what clinicians expect.
“Before concluding that most patients fail to take opioids and benzodiazepines correctly, we should take into account that urine tests sent to national laboratories reflect a skewed subset of patients who receive prescriptions,” says Kertesz, who reviewed the study. “Additionally, laboratory requisitions prepared by office staff are not likely to perfectly reflect what is prescribed. Urine tests convey a signal requiring interpretation followed by careful, patient-centered decisions.”
The study also found that 28.3% of women prescribed one of the drugs were found to be using the potentially deadly drug combination compared to 22.2% of men. Also, Medicare patients prescribed one of the drugs used the concurrent drugs significantly more than those with commercial or private payer health insurance.