Polypharmacy in Older Americans a Cause for Concern

March 22, 2016

A new study in JAMA Internal medicine has found that the concurrent use of interacting medications has increased since 2005 and that 15% of older adults are potentially at risk for a major drug-drug interaction.

Prescription medications, over-the-counter (OTC) medications, dietary supplements…the list of the number of medications that an individual is exposed to can be ever-expanding—especially so if the person suffers from comorbidities, which is a common occurrence in geriatric patients. Now a new study has found that the concurrent use of interacting medications has increased since 2005 and that 15% of older adults are potentially at risk for a major drug-drug interaction.

Researchers at the University of Illinois at Chicago and at Johns Hopkins collaborated on this study to conduct in-house interviews and direct medication inspection of adults in the age group of 62 to 85 years. The interviews were first conducted in 2005-2006 and again in 2010-2011, to compare and contrast prevalence of medication use and the concurrent use of prescription and OTC medications and dietary supplements. Additionally, the prevalence of drug-drug interactions was also monitored.

The increase in polypharmacy (use of multiple medications) “Is a concern from a public health standpoint, because it’s getting worse,” said Dima Qato, PharmD, MPH, PhD, from the University of Illinois at Chicago and lead author on the study, in an interview with Reuter’s.

More than 2000 adults were interviewed during both times periods, with a mean age of 70.9 years in 2005-2006 and 71.4 years in 2010-2011. From 2005-2006 to 2010-2011, the study observed the following:

  • The use of at least 1 prescription medication increased from 84.1% to 87.7% (P = .003)
  • Concurrent use of at least 5 prescription medications increased from 30.6% to 35.8% (P = .02)
  • OTC medication use declined from 44.4% to 37.9% (P&thinsp;<&thinsp;.001)
  • Use of dietary supplements increased from 51.8% to 63.7% (P&thinsp;<&thinsp;.001)

Additional analysis based on these trends in use of medications and supplementary products found that in the 2010-2011 time period, a little over 15% of the geriatric population was at greater risk of a major drug-drug interaction, nearly double the 8.4% in 2005-2006 (P&thinsp;<&thinsp;.001).

Further, a majority of these interactions involved those medications and dietary supplements that saw an increased use in 2010-2011.

“I think we have to keep in mind that while it’s important to improve access to medications, we need to make sure they’re used safely,” said Qato.

In an invited commentary in the same issue of JAMA Internal Medicine in which this article was published, Michael A. Steinman, MD, a geriatrician, writes, “The number of medications a person uses is by far the strongest risk factor for medication-related problems. As the number of medications rises, adverse drug reactions become more common. Adherence worsens. Out-of-pocket costs rise. Drug-drug interactions increase. The use of potentially inappropriate and unnecessary medications escalates.”

Reference

Qato DM, Wilder J, Schumm LP, Gillet V, Alexander GC. Changes in prescription and over-the-counter medication and dietary supplement use among older adults in the United States, 2005 vs 2011 [published online March 21, 2016]. JAMA Intern Med. doi:10.1001/jamainternmed.2015.8581.