A new study by one of the nation’s largest drug screening companies found that six out of ten Americans tested are misusing prescription drugs. But contrary to popular belief, the “misuse” is more likely to mean that patients are not taking any medication — rather than taking too much.
The national study by Quest Diagnostics (NYSE:DGX) is one of the largest to examine trends in the use of both legal and illegal drugs. It is based on an analysis of over 220,000 urine drug screens from 49 states and the District of Columbia that were analyzed by Quest laboratories in 2011 and 2012.
Patients were tested for up to 26 commonly abused prescription medications, such as sedatives and opioid painkillers, and illicit drugs, such as marijuana and cocaine. The urine samples came from patients enrolled in drug monitoring programs, so they are not representative of the general population.
Forms of misuse, or inconsistent results, include taking non-prescribed drugs, not taking a prescribed drug, or using an illicit drug.
The analysis found that about 60 percent of patients failed to use their prescription drugs as directed by their physicians. Marijuana was the most misused drug, with non-prescribed marijuana detected in about one out of four patients with inconsistent results. Nearly half of the patients (45%) who used marijuana recreationally also used other non-prescribed drugs, such as sedatives or opioids.
But a large number of patients also showed the presence of no drugs in the urine samples, including medications ordered by their physicians. About 42% of the patients had no drugs in their system in 2012, compared to 40% in 2011. The report speculates that financial constraints may have limited the patients’ ability to buy medications and, if they were purchased, some of the drugs may have been diverted or sold illegally.
Opioid painkillers such as hydrocodone (Vicodin) and oxycodone (OxyContin) were by far the most widely prescribed medications (69% in 2012 and 71% in 2011). The findings suggest that despite increased public attention to the so-called epidemic of prescription drug abuse, Americans are still asking for and doctors are still prescribing opioid painkillers in large numbers.
“Despite public education and publicity surrounding the dangers of prescription drug abuse, our study shows that misuse rates continue to be alarmingly high for opioids and other powerful medications,” said F. Leland McClure, PhD, pain management director at Quest Diagnostics. “We are hopeful that recent efforts by policy makers and public and private health professionals will help to rein in the nation’s prescription drug epidemic.”
Other key findings in the study:
- Among patients with inconsistent test results, evidence of marijuana was found in more than one in four (26%), followed by opiates (22%), benzodiazepines (16%), oxycodone (14%), cocaine (8%) and methadone (6%).
- About one in three patients with inconsistent results tested positive for a prescribed drug and at least one additional drug.
- Men and women misused prescription drugs equally.
- Medicaid recipients had the highest rates of misuse, at 70%, followed by patients covered by private insurers (59%) and Medicare (58%).
“While we had hoped for a noteworthy decline in misuse rates in 2012 compared to 2011, this was not the case,” said Harvey W. Kaufman, MD, senior medical director, Quest Diagnostics. “Not only is prescription drug misuse potentially dangerous for patients, it also contributes to healthcare waste and illegal activity. Our data underscores our nation’s need for better solutions for promoting responsible use of prescription drugs.”
A similar study, conducted last year by Ameritox, found that one in three urine samples (35%) contained no evidence of a prescribed pain medication.
The Centers for Disease Control and Prevention attributes 22,134 deaths in the U.S. in 2010 to prescription drug overdoses, a four-fold increase from 1999.