Medicare Part D coverage linked to increased use of antibiotics

The use of antibiotics increased in response to cuts in out-of-pocket prices after Medicare Part D went into effect, according to a study published in the latest edition of the Archives of Internal Medicine.

To investigate the relationship between antibiotic use and the change in drug coverage, researchers at the University of Pittsburgh Graduate School of Public Health compared insurance claims data from a large Medicare Advantage plan two years before and two years after implementation of Part D. Outcomes included the likelihood of using any oral antibiotics and major antibiotic subclasses among 35,000 older adults, and rates of antibiotic use among those with pneumonia and other acute respiratory tract infections.

For pneumonia, Part D implementation was associated with a triple increase in the rates of antibiotic treatment among those previously lacking drug coverage. Given the high mortality rate associated with community-acquired pneumonia among seniors, the authors called the finding encouraging.

Other findings, however, were deemed troubling. The researchers found increases in antibiotic use for other ARIs, such as sinustitis, pharyngitis, bronchitis, and nonspecific upper respiratory tract infection, for which antibiotics generally are not indicated.

While antibiotic prescription fill rates did not change for ARIs for those whose drug coverage did not change, the groups that moved from "limited-or-no drug coverage" to "Part D" saw higher antibiotic fill rates for ARIs.

"Our study suggests that reimbursement may play a role in addressing the substantial role of inappropriate antibiotic prescribing and use," the authors wrote. They added that changes in patient cost-sharing could be another way to alter patient/provider behavior.

To learn more:
- read the Archives of Internal Medicine article
- read the article in Medical News Today
- here's the Drug Store News article