Evidence lacking on efficacy of prescription drug monitoring programs

There isn't enough evidence to determine whether prescription drug monitoring programs (PDMPs) increase or decrease overdoses, a study found.

To examine whether such programs were associated with changes in nonfatal and fatal overdoses, to identify features of programs associated with those outcomes, and to investigate unintended consequences of the programs, researchers reviewed the published literature for observational studies. Seventeen articles met the inclusion criteria. Articles examined PDMP implementation only (n=8), program features only (n=2), PDMP implementation and program features (n=5), PDMP implementation with mandated clinician review combined with pain clinic laws (n=1), and PDMP robustness (n=1).

Results were published online May 8 by Annals of Internal Medicine.

Of the 17 included studies, evidence from three was insufficient to draw conclusions about an association between PDMP implementation and nonfatal overdoses. Another 10 studies linked PDMP implementation to reductions in fatal opioid overdoses. Features associated with reductions included mandatory review of PDMP data by clinicians before writing prescriptions, frequent (at least weekly) updates of PDMP data, clinician authorization to access PDMP data, and monitoring of nonscheduled drugs.

Of the six studies examining the relationship between PDMP enactment and heroin-related overdoses, three found a statistically significant post-implementation increase in these events. The authors noted that heroin substitution may have increased after PDMP-inspired restrictions on opioid prescribing and cautioned that programs aimed at reducing prescription opioids should also address the supply and demand of illicit opioids.

Research is needed to identify a set of best practices and complementary initiatives to address potential consequences of PDMPs, the authors wrote. Programs that have adopted best practices, such as real-time reporting and proactive provision of unsolicited patient reports to clinicians, may reduce “doctor shopping,” as well as the overall supply of prescription opioids on the illicit market, they said.

“A PDMP's ability to influence population health probably arises from its unique set of administrative features,” the authors wrote. “Future studies will have to consider this variation in features to develop a set of empirically based best practices that result in the greatest reduction in prescription opioid-related harm and mitigate any potential unintended consequences of PDMPs, such as heroin-related harms.”

An accompanying editorial noted that PDMPs are not a panacea, but just one program among many initiatives to curb opioid abuse.

“The basis for PDMP development was the reasonable idea that stricter monitoring of prescribing would deter overprescribing, diversion, and prescription opioid misuse and result in fewer adverse outcomes, such as overdose,” the editorial stated. “Yet, we should not automatically assume that PDMPs are effective.”

A separate research letter published May 1 by JAMA found a significant increase in illicit synthetic opioid involvement in overdose deaths involving prescription opioids, heroin, and all other illicit or psychotherapeutic drugs from 2010 through 2016.

Among the 42,249 opioid-related overdose deaths in 2016, 19,413 involved synthetic opioids, 17,087 involved prescription opioids, and 15,469 involved heroin. Synthetic opioid involvement in these deaths increased significantly from 14.3% of opioid-related deaths in 2010 to 45.9% in 2016 (P<0.01 for trend).

“Lack of awareness about synthetic opioid potency, variability, availability, and increasing adulteration of the illicit drug supply poses substantial risks to individual and public health,” the research letter stated. “Widespread public health messaging is needed, and clinicians, first responders, and lay persons likely to respond to an overdose should be trained on synthetic opioid risks and equipped with multiple doses of naloxone.”

Also, the CDC announced on April 23 that clinicians should maintain a high index of suspicion for vitamin K-dependent antagonist coagulopathy in patients with a history of using synthetic cannabinoids such as K2, Spice, and AK47. Patients may present with symptoms unrelated to bleeding, such as appendicitis, or be asymptomatic and have numerical coagulopathy.

Since an index case was identified on March 8, 2018, in Illinois, at least 160 people may have been anti-coagulated without clinical signs of coagulopathy due to synthetic cannabinoid use and presented to health care facilities with serious unexplained bleeding, mostly in Illinois but also in Florida, Indiana, Kentucky, Maryland, Missouri, Pennsylvania, Virginia, and Wisconsin. There have been at least three fatalities.

The CDC said that all patients should be asked about history of illicit drug use and that all synthetic cannabinoids users, regardless of presentation, should be screened for vitamin K-dependent antagonist coagulopathy by checking their coagulation profile (e.g., international normalized ratio and prothrombin time).