Inappropriate medications raise the risk of adverse drug events among older adults
Research Activities, November 2009
Reducing the use of inappropriate medications by older adults, along with decreasing the number of medications taken by this population, can reduce adverse drug events (ADEs), conclude Elizabeth A. Chrischilles, Ph.D., of the University of Iowa, and her colleagues. Because they take multiple drugs, older adults are especially susceptible to ADEs, which have been found to cause more deaths annually than motor vehicle accidents, breast cancer, or AIDS. In a prospective study of 626 Iowa Medicare recipients, the researchers found that 22 percent of the group reported experiencing an ADE within the past year. Slightly more than half (51.4 percent) received at least one potentially inappropriate medication. Individuals with any inappropriate medication use had double the risk of a self-reported ADE than did those without inappropriate medication use, after adjusting for the patient's age, number of medications taken, and the number of mobility limitations.
The most frequent inappropriate medications were drugs contraindicated for use in older adults and drugs that can produce a drug-disease interaction. Drug-drug interactions and duplications of drugs in the same therapeutic class were less common. An earlier paper on this group of patients found that 83 percent of them contacted their doctor regarding the ADE(s) they experienced, and more than half (56 percent) stopped taking the medication they thought responsible. The study was funded in part by the Agency for Healthcare Research and Quality (HS16904). More details are in “Inappropriate medication use as a risk factor for self-reported adverse drug events in older adults,” by Dr. Chrischilles, Rachel VanGilder, Ph.D., Kara Wright, M.S., and others, in the June 2009 Journal of the American Geriatrics Society 37(6), pp. 1000-1006.