Roughly three in five Americans now take prescription drugs, from antidepressants to high cholesterol treatments. That number has risen 8 percent from 1999 to 2011, according to a new study.
The lead author of the study, Elizabeth D. Kantor of Memorial Sloan Kettering Cancer Center in New York, said that it is difficult to say why prescription drug use is on the rise. “For example, we know that older adults tend to take more medications than younger adults, and so we’d expect prescription drug use to increase as the U.S. population ages,” Kantor told Reuters.
However, “something beyond the aging of the U.S. population appears to be driving the increase in prescription drug use,” Kantor added.
The study, published Tuesday in the Journal of the American Medical Association, not only found that prescription drug use among people 20 and older rose 8 percent, but it found that the percentage of people taking five or more prescription drugs nearly doubled. The Washington Post reports that the number jumped from 8 to 15 percent.
Kantor’s team looked at information from seven cycles of the National Health and Nutrition Examination Survey (NHANES) including 37,000 U.S. adults ages 20 and older. The survey asked about prescription drug use over the past 30 days.
According to the report, the most significant increase in prescription drug use appeared in people 40 and older. The drug use rose overall, and so did “polypharmacy.” This is the use of five or more drugs at the same time.
Statinsfor high cholesterol, blood pressure medications and antidepressants all increased along with a specific kind of stomach acid blocker called proton pump inhibitors. According to Reuters, the most common was simvastatin (Zocor), a drug for high cholesterol that is being taken by 8 percent of U.S. adults.
Kantor said that it is hard to say if the increase in prescription drug use is a real problem since an increase in a drug could be benefiting the population.
So what could be the cause? Kantor said that new drugs enter the market and old drugs lose patent protection and become less costly, Reuters reports. She also said that patterns of prescription drug use evolve with changes in clinical guidelines and scientific advances.
According to Washington Post, obesity could be a driving force in the increase of prescription drug use because of the increased types of drugs. However, Kantor cautioned readers against forming too many conclusions from the study. Most likely, the reasons vary from drug to drug.
“There’s so much going on in each area, it’s hard to draw concrete conclusions,” Kantor said. “Each drug class stands on its own.”