New research shows deaths from heart disease have declined dramatically over the last few decades in people over 65.

But that's not true for people under 55, especially women. 

“The next step would be trying to understand why this younger population is not showing the improvement the older patients do, is it because of the traditional risk factors and they're citing increases in obesity and diabetes, in this population.” 

Researchers at Emory University also point out that diabetes and obesity may pose a greater heart disease risk for younger women. 

Heart disease is still the number one killer of both men and women in the U.S. It's responsible for one in every four deaths.

Cardiologist Alexander Gorodnitskiy says this study highlights the need to rethink strategies that focus on traditional risk factors like high blood pressure and cholesterol. 

“Maybe it's time to look outside of those things and look at stress management, sleep, all kinds of quality of life issues.”

Experts say depression is also a powerful predictor of heart disease in young women.