Americans have made major strides in, but two new studies suggest one group — the poor — still lags behind.
Risk of heart disease among middle-class and rich Americans declined 20 percent between 1999 and 2014, researchers said.
But those levels changed little among the poor, who are as likely to have, to smoke and have other risk factors for heart disease and stroke as they did 15 or 20 years ago, the researchers found.
"Adults in all income strata have not benefited equally from efforts to improve control of cardiovascular risk factors in the United States," said Dr. Ayodele Odutayo, lead researcher of one of the studies.
Public health must focus on reducing income disparities in, particularly blood pressure and smoking, said Odutayo. He is with St. Michael's Hospital in Toronto.
"This not only includes expanding access to health insurance, but also ensuring that insurance plans that cover adults with lower incomes provide adequate management and counseling related to cardiovascular risk factors," Odutayo said.
For the study, Odutayo and his colleagues used the 1999-2014 U.S. National Health and Nutrition Examination surveys to collect data on more than 17,000 adults, ages 40 to 79. They were grouped according to income level: high, middle or at or below the federal poverty level — $24,600 annual income for a family of four.
The researchers found that the percentage of poor people with an absolute risk for cardiovascular disease of 20 percent or more stood at 15 percent in the 1999-2004 period. But, it rose to nearly 17 percent in 2011-2014.
In addition, average systolic blood pressure — the first number in a blood pressure reading — among the poorest Americans fell just 1 point from 128 mm Hg to 127 mm Hg.
Similarly, smoking among poor Americans fell only from about 37 percent to 36 percent, the report said.
However, for more prosperous adults, the percentage of those with a cardiovascular risk of 20 percent or greater dropped from 12 percent to 10 percent by 2011-2014.
Average systolic blood pressure declined from 126 to 122 mm Hg for middle- and high-income people, and smoking declined from 14 percent to less than 9 percent, the researchers found.
Trends in the number ofand the average total cholesterol level did not change by income, the researchers found.
The paper was published online June 7 in the journal JAMA Cardiology.
A second study in the same issue of the journal also foundbased on income.
During the last decade, numerous initiatives to improve cardiovascular health among low-income individuals have been tried — and failed, said lead author Adam Beckman, a health consultant in Bethesda, Md.
"Despite these efforts, the rates of high blood pressure decreased for high-income people, but increased for low-income people," said Beckman, whose company is called Aledade Inc.
Beckman's study looked at risk factors for adults 25 and older using U.S. national survey data from 2005 to 2014. He and his colleagues obtained similar but slightly different results than Odutayo did in his study.
"Rates of diabetes decreased for high-income people, but did not change for the low-income people," Beckman said.
Rates ofincreased for both high- and low-income groups, but increased more for the poor than the well-off, he said.
Smoking fell among both higher- and lower-income populations, but decreased more for wealthier than poorer people, Beckman said.
"Our results emphasize that we need to more rapidly identify and scale effective approaches to improve cardiovascular health for low-income communities," he added.
One expert said the results of these studies aren't surprising.
"But, the implications of those results are shocking," said Dr. Donald Lloyd-Jones, a spokesman for the American Heart Association.
Poor people aren't getting the publicand obtain good medical care so they can control their blood pressure -- or prevent high blood pressure in the first place, said Lloyd-Jones. He's chair of preventive medicine at Northwestern University's Feinberg School of Medicine in Chicago.
"We have made this bed and we have got to lie in it, and the burden of that falls disproportionately on poor people. The safety net is only getting thinner and more frayed," Lloyd-Jones said.
If certain provisions of the Affordable Care Act are gutted, as Republican lawmakers hope, the negative effects will fall mostly on the poor, he added.