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More than a third of adults in the US take at least three prescription medications and many are rationing them, according to a new CDC report.
CNN  — 

Millions of adults in the United States are not taking their medications as prescribed because of costs, according to a new report from the US Centers for Disease Control and Prevention.

Most adults between the ages of 18 and 64 took at least one prescription medication in 2021. But more than 8% of them – about 9.2 million people – said they tried to save money by skipping doses, taking less than prescribed or delaying a prescription fill, according to the CDC data.

Although average drug costs did not increase in 2021, the number of prescriptions did, and that raised spending. More than a third of adults took at least three prescription medications in 2021, according to the CDC. And data from health analytics company IQVIA shows that total prescription drug costs rose nearly 5% from 2020 to 2021, to $63 billion.

Delaying or adjusting medications can lead to more serious health implications and raises the potential for even higher costs if additional treatments become necessary.

Earlier research found that about 1 in 6 people with diabetes were rationing their insulin.

“The main takeaway is that 1.3 million people rationed insulin the United States, one of the richest countries in the world,” said Dr. Adam Gaffney, a pulmonologist and critical care doctor at Harvard Medical School and Cambridge Health Alliance and lead author of that study. “This is a lifesaving drug. Rationing insulin can have life-threatening consequences.”

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The new CDC data shows vast disparities in how often drug costs cause people to not take their medications as prescribed.

Nearly a quarter (23%) of adults without health care coverage did not take their medications as prescribed to reduce costs, compared with less than 7% of people who had private insurance.

Those living with disabilities were also about three times more like than those without disabilities to ration their medications, as were people with fair or poor health compared with those with good health.

Women were also more likely to than men, according to the CDC data.

For this report, researchers from the National Center for Health Statistics analyzed responses to the 2021 National Health Interview Survey, a representative survey of US households.