Gerontologists have long recognized that the elderly can have a very different physiology from the young. And among these differences can be bad reactions to drugs that would be perfectly well tolerated by younger people.
A new study by Duke Medical Center researchers indicates that far too many Americans over the age of sixty-five hold prescriptions for drugs that, by established criteria, are risky for them. Kevin Schulman, director of the Center for Clinical and Genetic Economics, and his colleagues found that one in five elderly Americans studied filled a prescription for at least one "drug of concern" over the course of a year. These are drugs on the "Beers list," named after Mark Beers of the University of California at Los Angeles, who led the team that developed it. The list includes anti-depressants, anti-anxiety drugs, and many common painkillers.
In the study, the Duke team analyzed the prescriptions filled for all patients over sixty-five who filed claims in 1999 through the outpatient prescription claims database of AdvancePCS (now part of Caremark Rx, Inc.). The study was published last summer in the Archives of Internal Medicine.
People over the age of sixty-five make up less than 15 percent of the U.S. population, yet they account for nearly one-third of drug consumption, says Schulman. Elderly individuals more often have multiple chronic conditions, increasing the likelihood that they take several drugs concurrently, he adds. Furthermore, many drugs present increasing risk for people as they age, because of changes in metabolism and excretion, and have effects complicated by the number of prescription drugs taken.
Says Lesley Curtis, assistant research professor in internal medicine at Duke Medical Center and lead author of the study, "Although criteria for drugs to avoid in the elderly have been around for a long time, the amount of potentially inappropriate prescribing for older patients remains really high."
Elderly Receiving Risky Drugs
November 30, 2004