As one might expect, the percentage of delayed care was highest among the lowest paid—among households earning less than $40,000 annually.

The highest percentage of Americans since Gallup started asking the question are letting serious medical conditions go without care, because they can't afford it.

That's according to a new Gallup report, which finds that 25 percent of respondents say they've foregone medical care because of the cost for a serious condition—up from 19 percent a year ago and reflecting a near-50 percent increase in that number since Gallup began asking about it in 2001. And that can have serious repercussions for the economy.

Says the report, "Such delays in medical treatment, whether for injuries, illnesses or chronic conditions, can have significant implications for the economy and health care system, but also the political climate." Some of those implications include reduced productivity and increased health care costs—a double-whammy that will have a notable impact on the economy.

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And while it's to be expected that lower-income families are skipping care, and probably too that people with pre-existing conditions are among the procrastinators, Democrats are also more likely than Republicans to say that they've held off treatments because of care cost. That's up 12 points since 2018 among Democrats, the report says, compared with three- and five-point increases among Republicans and independents, respectively.

Less serious conditions came in for delays, too, raising the overall percentage of postponed care to 33 percent (a high tied with 2014). And as one might expect, the percentage of delayed care was highest among the lowest paid—among households earning less than $40,000 annually, 36 percent—a rise of 13 points from 2018—said they delayed getting treated for a serious health condition.

In addition, a third of U.S. adults say their family couldn't afford care in the last year—and the problem doesn't appear to be tied to being uninsured, since the report also finds that the percentage of uninsured is 11 percent in the poll; that's within the 9–11 percent range the poll has reflected annually since 2015. In addition, the percentage delaying care is up by a similar proportion among those covered by private health insurance or Medicare/Medicaid as well as among the uninsured.

The Hill points out that there's a 23-percentage-point income gap in Americans delaying treatment in 2019, though early in the Obama administration the income gap averaged 17 points. That gap narrowed to an average of 11 points from 2015 to 2018 after the first few years of the Affordable Care Act implementation, according to Gallup.

Read more: 

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• 10 states where consumers are more likely to skip the doctor due to cost