The rates of heart disease in the United States peaked in the 1960s and then began a steady decline mainly due to positive lifestyle changes as well as decline in smoking. However in recent years, heart disease has once again proved to be the number one killer.

Researchers from Mayo Clinic in Minnesota and the University of British Columbia in Vancouver examined the autopsy findings in Olmsted County from 1981 to 2004. Some 3,237 Olmsted County residents aged between 16 to 64 years had died during the study period.

Among them 425 people died from unnatural causes like accidents, suicide and murder. During autopsy some 8 percent of these people were found to be harboring significant coronary artery disease and 83 percent of them had clogged arteries, which is a harbinger for serious heart disease in future.

The researchers concluded that heart disease rates stopped declining after 1995 and in fact started increasing after 2000.

“Our finding that temporal declines in the grade of coronary artery disease at autopsy have ended, together with suggestive evidence that declines have recently reversed, provides some of the first data to support increasing concerns that declines in heart disease mortality may not continue,” the authors write in the February 11 issue of Archives of Internal Medicine.

According to the American Heart Association major risk factors for coronary heart disease include age, smoking, heredity, high blood pressure, high cholesterol levels, diabetes and obesity. The surging obesity rates in young people may in fact be contributing to an increase in heart disease numbers. Overall maintaining a healthy lifestyle and avoiding all risky habits will help in preventing heart disease.