Americans have halved their risk of dying from coronary heart disease over the last two decades by smoking less, watching their cholesterol and reducing their high blood pressure. Even though current therapies for heart disease have also contributed towards the drop, by far the biggest factor has been preventing heart disease from developing in the first place.

Coronary heart disease (CHD), or narrowing of the arteries, can eventually lead to chest pain and heart attack. Its main cause is accumulation of hard cholesterol deposits in the arteries.

You can read about this in the September issue of the American Journal of Preventive Medicine.

Researchers used data from 1980 to 2000 and found that the greatest difference in death rates was due to primary prevention: reducing risk factors among healthy individuals. Smaller impact came from secondary prevention measures such as drugs or surgery for people with heart disease.

Lead author Fiona Young, Institute of Health and Society, Newcastle University, England, said:

Knowledge about what has caused these large mortality declines allows us to plan effective measures to reduce disease rates in the future.

The scientists collected data on total cholesterol level, systolic blood pressure and smoking prevalence from The National Health and Nutrition Examination Survey, a yearly national survey that represents the whole of the US population. They entered those statistics into a model that estimates changes in heart disease mortality between two points in time.

Individuals who had not yet had a heart attack accounted for 79% of the drop. The remainder came from people with symptoms of heart disease, through secondary prevention measures such as surgery or medication in addition to risk factor control.

Young said:

We were surprised by the small proportion of the mortality fall attributable to primary preventive drug interventions such as statins and blood pressure tablet

This was partially because so few healthy people in a group develop heart problems, even if their risk factors are not treated, she said. And of patients who are prescribed these medicines, many either don’t take them regularly or stop completely.

The results prove again that prevention, prevention, prevention is important in staying healthy, according to Paul Sorlie, PhD, chief of the epidemiology branch of the Heart, Lung, and Blood Institute, part of the National Institutes of Health.

Sorlie said:

Both primary and secondary prevention are important. If you don’t have CHD, there is a lot you can do to keep healthy by lowering blood pressure and cholesterol, and stop smoking. If you have had a heart attack, you can impact on your future health, prevent a second heart attack, and reduce the risks of dying by working on these risk factors. Don’t give up because you have CHD.

Nieca Goldberg, MD, cardiologist and spokesperson for the American Heart Association, said:

This shows us we are seeing a reduced rate of CHD because we are getting more successful in reducing risk factors. The things we have been telling people to do for years really work. This study reminds us of that again.

“Coronary mortality declines in the U.S. between 1980 and 2000: quantifying the contributions from primary and secondary prevention.”
Young F, et al.
Am J Prev Med 39(3), 2010.

Written by Christian Nordqvist