A new study finds that older adults are mixing medications and dietary supplements, putting them at risk for a major drug interaction that could have serious consequences. The study, published in JAMA Internal Medicine found that nearly 36 percent of older Americans are taking five or more prescription medications per day, up from 30 percent a few years ago, and many are mixing them with non-prescription supplements.
Dima M. Qato, Pharm. D., M.P.H., Ph.D., of the University of Illinois at Chicago, and coauthors conducted the study, which included 2,351 participants in 2005-2006 and 2,206 in 2010-2011 who were between the ages of 62 and 85. In-home interviews and direct medication inspection were performed.
The authors report:
- Concurrent use of at least five prescription medications increased from 30.6 percent to 35.8 percent over the study period.
- Concurrent use of five or more medications or supplements of any type increased from 53.4 percent to 67.1 percent.
- Use of over-the-counter medications declined from 44.4 percent to 37.9 percent.
- Dietary supplement use increased from 51.8 percent to 63.7 percent. Multivitamin or mineral supplements and calcium were the most commonly used supplements during the study period.
- About 15.1 percent of older adults in 2010-2011 were at risk for a major drug interaction compared with an estimated 8.4 percent in 2005-2006. For example, preventive cardiovascular medications and supplements were increasingly used together in interacting drug regimens.
“These findings suggest that the unsafe use of multiple medications among older adults is a growing public health problem. Therefore, health care professionals should carefully consider the adverse effects of commonly used prescription and nonprescription medication combinations when treating older adults and counsel patients about these risks,” the authors conclude.
Next leap forward
The study illustrates the need to “take the next leap forward,” said Michael A. Steinman, M.D., of the University of California, San Francisco, in an accompanying commentary.
“We need to create systems that support an ongoing process of monitoring medications. Such systems would help us periodically assess the benefits, harms and ongoing need for each of a patient’s medications, as well as the reasonableness of the medication regimen as a whole,” Steinman said. “These systems could also help physicians with deprescribing, for example by supporting gradual down-titration of a medication and monitoring patients for adverse drug withdrawal reactions after a drug is stopped. This is hard. Many attempts to improve these elements of prescribing quality have had disappointing results. Yet, it is within our grasp.”