TEN PERCENT OF ER VISITS IN
ELDERLY DUE TO DRUG REACTIONS

A significant number of elderly adults' emergency department visits are related to the multiple drugs so many must take every day.

A review of older patients' medical charts revealed that nearly 11% of emergency department visits were due to complications from medications such as aspirin and ibuprofen, antibiotics, diuretics, blood sugar-lowering drugs, chemotherapy drugs and heart medications.

Overall, nearly one third of all study patients were taking medications that put them at risk for at least one potentially dangerous drug interaction. About 91% of the 283 patients, who ranged in age from 65 to 101, were taking at least one prescribed or over-the-counter medication. On average, patients were taking four drugs.

Patients had an average of three medical conditions, which included heart disease, diabetes, respiratory problems and stroke. About 13% of patients took only one drug, while nearly 24% took two or three, 23% took four or five, and 18% took six or seven drugs. About 13% of patients took at least eight different drugs daily. Not surprisingly, the frequency of adverse interactions rose in tandem with the number of drugs taken.

No patients on only one drug had a medication-related emergency. But adverse reactions increased to about 17% among patients taking more than six drugs, from about 12% among patients taking two to five medications.

However, none of the complications seen in these study patients were directly caused by a drug interaction, but were instead related to a specific drug in their regimen.

Still, the authors point out that taking several drugs simultaneously can lead to an adverse reaction in a number of ways, including through interactions in which drugs cancel or interfere with the effects of another.

Acetaminophen, for instance, can increase the anti-clotting effect warfarin has in the blood, raising the risk of bleeding. Taking both the blood-pressure drug enalapril and potassium supplements can raise the risk of electrolyte imbalances and irregular heartbeat.

However, the study found that medication regimens were rarely adjusted to lower the risk of adverse reactions by the time patients were discharged from the emergency department.
Annals of Emergency Medicine December 2001;38:666-671