WASHINGTON, Nov. 3 (UPI) -- A significantly higher number of Americans are using prescription drugs now than were a decade ago, researchers report in a new study.
The study shows the changing needs of the population and advances in medical care, researchers said, suggesting assessments of prescription use be updated to reflect underuse, misuse and abuse as more people are treated with prescription drugs.
Many of the most used drugs reflect the effects of metabolic syndrome, a group of conditions tied to obesity and diet.
"Eight of the 10 most commonly used drugs in 2011-2012 are used to treat components of the cardiometabolic syndrome, including hypertension, diabetes, and dyslipidemia," researchers wrote in the study, published in the Journal of the American Medical Association. "Another is a proton-pump inhibitor used for gastroesophageal reflux, a condition more prevalent among individuals who are overweight or obese. Thus, the increase in use of some agents may reflect the growing need for treatment of complications associated with the increase in overweight and obesity."
Researchers analyzed data on 37,959 adults aged 20 and older that was gathered as part of the National Health and Nutrition Examination Survey from 1999 to 2012. The data showed that overall prescription drug use increased from about 51 percent of the United States population to 59 percent, with the most significant increases in use among people aged 40 to 64 and 65 years and older.
The prevalence of polypharmacy -- the use of five or more prescription drugs at once -- increased from 8 percent to 15 percent. With regard to individual conditions, medications used for hypertension increased from 20 to 27 percent, drugs used to treat hyperlipidemia increased from 7 percent to 17 percent, and the use of antidepressants rose from 7 percent to 13 percent. Additionally, 11 of the 18 drug classes used by more than 2.5 percent of the population increased in use during the 13-year study period.
The authors say more research is needed to explain the increase of prescription drug use. They argue the increase in obesity in the United States may explain some of the increases, but not all of it. There is also some concern about the increase in the number of people being treated with five or more drugs.
"When we're starting to see more and more adults using five or more drugs, it does raise a concern about the potential for drug interaction," Dr. Elizabeth Cantor, an epidemiologist at Memorial Sloan Kettering Cancer Center and lead researcher on the study, told NPR, adding that the study "might raise the question of how much of this increase in prescription drug use might be attributable to obesity, as we know that the prevalence of obesity has increased among adults in the United States."
Although opioid-based painkillers and similar drugs do not appear in the top ten drugs in the study, epidemics of opioid misuse and abuse, as well as drugs used to treat psychiatric conditions, have raised concerns about the well-being of the population.
Another just-released study showed abuse of drugs and alcohol has led to an "epidemic" of deaths among white, middle-class adults, which is blamed on both mental and physical health issues.