Sam Edwards | Caiaimage | Getty Images

After more than a decade of declines in heart failure-related deaths in the United States, more Americans are now dying from the condition as the obesity and diabetes epidemics rage on, according to a new study by Northwestern Medicine. The increase in heart failure deaths was especially high in adults ages 35 to 64, particularly in young black men. "We've seen a lot of progress in the last two decades with certain medical advancements," said Dr. Sadiya Khan, who authored the study, but "these data are suggesting that we need to do more in the realm of prevention." Khan said this trend is expected to get worse because of the number of Americans who suffer from obesity and diabetes, which negatively impact heart health. More than 93 million American adults are obese, while 30 million live with diabetes.

Heart failure is when the heart muscle doesn't pump blood as efficiently as it should. It can cause shortness of breath, swelling in the legs and feet, weakness, persistent coughing and death. About 5.7 million U.S. adults live with the condition. The study, which examined more than 47 million death certificates from 1999 to 2017 using a Centers for Disease Control database, found the number of people dying from heart failure is slowly creeping up after years of reductions in death rates. The number of Americans ages 35 to 84 who died from heart failure decreased from 79 deaths per 100,000 people in 1999 to 54 deaths per 100,000 people in 2012. But in 2017, there were 59 deaths per 100,000. The increase in heart failure deaths was even more notable for young adults, but the study found black men and women were affected much more than white men and women.