FDA drug risk communications have ‘unpredictable’ impact
MedWire News: The impact of communications provided by the US Food and Drug Administration (FDA) regarding the unanticipated risks associated with approved medicines is "varied and unpredictable," according to a review of 20 years' research.
The review, published in Medical Care, looked at the impact of studies about FDA warnings and alerts published over the past 20 years.
"Communicating risk to large groups of people is a complex science," said G Caleb Alexander of The University of Chicago, Maryland, USA, in a press release. "But success or failure at this can have significant consequences. As such efforts become more and more common - with the FDA's mandate to establish a more active surveillance system - we will need a better understanding of how to make them work and where they can go wrong."
The researchers identified 49 reports that primarily assessed the consequences of FDA risk communications for prescription drugs. They covered 16 medicines or therapeutic classes; one third of the articles focused on antidepressants.
They were able to divide the studies into four categories: warnings about serious adverse events, recommendations against use in specific patient populations, preventing harmful drug-drug interactions, and calls for more laboratory or clinical monitoring.
Drug-specific warnings about adverse events were most effective as they were associated with particularly large decreases in utilization of that particular drug. However, this impact varied depending on the drug.
For example, patients stopped using the diabetes drug rosiglitazone and switched to alternatives after the FDA warned it was associated with cardiovascular events, but a similar warning about a class of asthma medication did not result in such a change. The FDA warned long-acting beta antagonists should not be used without an asthma-controller medication, but rates of controller medication did not increase.
Alexander and team also found that FDA recommendations advising more clinical or laboratory monitoring generally led to decreased use of the drug but only modest, short-term increases in monitoring. The category of studies on communications targeting specific subpopulations showed that their impact spilled over to other, unaffected groups.
"The most effective communications were the simplest, those that were specific, where alternatives were available, and where the messaging was reinforced over time," said lead author Stacie Dusetzina (Harvard Medical School, Boston, Massachusetts, USA) in a press release.
"[This study] suggests the importance of continuing to characterize the effect of advisories and warnings on a variety of behaviors to enhance the science of risk communication regarding prescription drugs," the researchers conclude.
By Chloe McIvor