Tuesday, August 17, 2004

20% of Older Americans Taking Risky Drugs
By Pat French

According to a new Duke study, more than 1 in 5 older Americans are being prescribed drugs likely to cause them problems.

Like infants and children, the elderly process drugs differently from healthy adults. In 1990, a specialist in elderly care, Mark H. Beers, MD, developed a set of criteria to measure the risk versus benefit of prescription drugs given to people in nursing homes. The criteria resulted in a list of drugs for which the possible risk outweighed any possible benefit. This so-called “Beers list,” since revised in 1997 and 2003, now includes 28 drugs or drug classes not appropriate for all patients over age 65 and 48 drugs/classes not appropriate for those with specific diseases or conditions. The list’s criteria since have been applied to assisted-living facilities, outpatient clinics, physician offices, and the community.

In a study published in the August 9/23 issue of the Archives of Internal Medicine, Dr. Lesley Curtis and colleagues at the DCRI and the Duke Center for Clinical and Genetic Economics (CCGE) present their analysis of how well physicians and hospitals are applying the criteria of the Beers list.

They analyzed prescription claims paid in 1999 through AdvancePCS (now part of Caremark Rx, Inc.) for anyone over age 65. Of the 765,423 people included in the study, more than 1 in 5 (21%) had received a prescription for at least 1 drug from the Beers list during 1999. Among this group, 16% had received 2 such prescriptions, and 4% had received 3 or more risky prescriptions.

Psychoactive drugs made up 40% of the Beers-list drugs prescribed to these patients, most often drugs for depression (Elavil, Lithium, Sinequan) and anxiety (Valium, Atarax). The remaining 60% of the prescriptions included muscle relaxants such as Flexeril, urinary control drugs such as Ditropan, antihistamines such as Phenergan, and anti-inflammatory drugs such as Indocin, among others.

People over age 65 make up less than 15% of the U.S. population, but they account for almost one third of prescription drug consumption. Older people also are more likely to have several medical conditions simultaneously, increasing the chance of harmful actions and interactions with prescription drugs.

The authors suggested several reasons for the high rate of apparent inappropriate use:

• The Beers criteria may be too rigid for a “real-world,” individualized setting.
• The true risk of these drugs to elderly patients is unknown. The best information about medication-related risk comes from randomized clinical trials, from which elderly patients often are excluded.
• Elderly patients often receive complex treatment regimens for multiple chronic diseases. Physicians (and patients) may not want to alter such regimens if there is no perception of harm.
• In some cases, the use of a “Beers drug” actually may be the best treatment, if its benefits outweigh the possible risks.

The investigators suggest several ways to reduce the numbers of inappropriate prescriptions among older patients, including computerized prescription entry systems with flags for drugs on the Beers list. Patients also should take an active role—whenever they receive a new prescription, they should ask whether the drug and dosage are safe, given their age.

Other Duke collaborators on the study were Drs. Truls Østbye, Veronica Sendersky, and Kevin Schulman. The study was funded by the Centers for Education & Research on Therapeutics (CERTs), for which Duke is the coordinating center, and the University of Arizona Health Sciences Center in Tucson.