Death rates from heart disease are rising for middle-aged adults — white women, in particular — according to a report released Wednesday by the Centers for Disease Control and Prevention.

The increase comes after more than a decade of decreasing death rates from heart disease for this age group. In fact, for other age groups — namely, those 20 to 44, and 65 and up — heart disease death rates did not increase.

Middle-aged adults are “losing ground,” said Dr. Sharonne Hayes, a cardiologist at the Mayo Clinic in Minnesota, who was not involved with the CDC report. And this is not the first time such findings have been reported; there have been hints for years.

“We’ve got to stop patting ourselves on the back” about the decreasing rates of heart disease deaths, Hayes told NBC News. “We’ve taken our feet off the gas pedal.”

The report, published by the CDC’s National Center for Health Statistics, found that heart disease death rates decreased for all adults ages 45 to 64 fell by 22 percent from 1999 to 2011, from 164.3 deaths per 100,000 people to 127.9 deaths per 100,000 people.

That positive trend, however, started to reverse from 2011 to 2017, when death rates increased by 4 percent.

While more research is needed to fully understand why heart disease death rates are rising in middle-aged adults, there are likely several factors at play, Hayes said.

Rates of risk factors, including obesity, a sedentary lifestyle and diabetes, are going up.

In addition, a lack of access to insurance, coupled with rising costs of medical care, can hit this age group particularly hard, Hayes said. Unlike adults ages 65 and up, who have access to Medicare, and younger adults, who may still be on their parents’ insurance or receive health insurance from work, middle-aged adults may have lost access to medical care.

Men vs. women

Notably, the increasing rates of heart disease deaths did not affect men and women equally. Middle-aged men still are more likely to die from heart disease than middle-aged women, but heart disease death rates among women rose 7 percent, compared with 3 percent in men, according to the report.

There are gender-based differences in heart disease, and doctors are “still playing catch up” in terms of research for treating heart disease in women.

“It may be that the treatments we apply to men may not be as effective for women,” Hayes said.

Middle-aged African American women still die from heart disease at much higher rates than white women. But during this time, heart deaths among white women, 45-64, increased at twice the rate. The CDC report doesn't address why.

Ultimately, Hayes said, the report should be a call to action.

“We’re going to have a generation at higher risk of dying from heart disease than their parents," she said.

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