By Reuters Staff
NEW YORK (Reuters Health) - Targeted urine drug testing (UDT) is more likely to turn up non-medical opioid use than random UDT in patients on long-term opioid treatment for cancer pain, according to new research.
Twenty-eight percent of randomly tested patients had abnormal UDT results, versus 43% of those who underwent targeted testing, Dr. Eduardo Bruera of The University of Texas MD Anderson Cancer Center in Houston and colleagues report in JAMA Oncology.
"Although the frequency of abnormal UDT in the random group was significantly lower than in the targeted group, it was still quite high, suggesting that routine random monitoring may be justified among patients with cancer receiving opioids," Dr. Bruera and his team write.
Previous studies of abnormal UDTs in patients on long-term opioids for cancer pain have been done in patients at increased risk of opioid abuse, they note, and there are no guidelines on when these tests should be ordered.
They compared medical records for 212 consecutive patients attending an outpatient clinic who underwent random UDT and 88 consecutive patients for whom a targeted UDT was ordered because of suspected illicit opioid use.
Median age was 60 in the random-UDT group and 53 in the targeted-UDT group. Women represented 53% of the random group and 51% of the targeted group.
Fifty-nine individuals had abnormal results on random UDT (28%). Of the 68 abnormal tests, 29% were positive for an unprescribed opioid and 52% for other illicit drugs.
In the targeted-UDT group, 38 individuals (43%) had abnormal findings. Twenty-nine percent of the abnormal tests were positive for unprescribed opioids and 43% for illicit drugs.
Excluding tests that were positive for marijuana (29 in the random-UDT group and 15 in the-targeted group), the rate of abnormal test results was 16% with random testing and 33% with targeted testing.
Factors independently associated with nonmedical opioid use included being younger, being male and having higher levels of anxiety.
In 19% of the abnormal tests in the random-testing group and 28% in the targeted-testing group the prescribed opioid was absent from urine, suggesting opioid diversion, the researchers say.
"This is particularly concerning because such opioids may end up being used by individuals other than patients and contribute to the risk for unintentional overdose or death," Dr. Bruera and colleagues write. "The presence of marijuana in urine may be of limited importance mainly because its classification as an illicit drug is currently debatable and general perception continues to evolve."
They conclude: "Ultimately, further studies are needed to guide clinical practice regarding the use of UDT among patients treated with opioids for cancer pain."
Dr. Bruera was not available for an interview by press time.
SOURCE: https://bit.ly/37l32FE JAMA Oncology, online February 6, 2020.