Profile of the Framingham Heart Study

(February 2006)

Cardiovascular disease (CVD) is the leading cause of death and serious illness in the United States. In 1948, the Framingham Heart Study -- under the direction of the National Heart Institute (now known as the National Heart, Lung, and Blood Institute; NHLBI) -- embarked on an ambitious project in health research. At the time, little was known about the general causes of heart disease and stroke, but the death rates for CVD had been increasing steadily since the beginning of the century and had become an American epidemic.

The objective of the Framingham Heart Study was to identify the common factors or characteristics that contribute to CVD by following its development over a long period of time in a large group of participants who had not yet developed overt symptoms of CVD or suffered a heart attack or stroke.

The researchers recruited 5,209 men and women between the ages of 30 and 62 from the town of Framingham, Massachusetts, and began the first round of extensive physical examinations and lifestyle interviews that they would later analyze for common patterns related to CVD development. Since 1948, the subjects have continued to return to the study every two years for a detailed medical history, physical examination, and laboratory tests, and in 1971, the study enrolled a second-generation group -- 5,124 of the original participants' adult children and their spouses -- to participate in similar examinations. In April 2002 the Study entered a new phase: the enrollment of a third generation of participants, the grandchildren of the original cohort. This step is of vital importance to increase our understanding of heart disease and stroke and how these conditions affect families. With the help of another generation of participants, the Study may close in on the root causes of cardiovascular disease and help in the development of new and better ways to prevent, diagnose and treat cardiovascular disease. The first phase of the Third Generation Study was completed in July 2005 and involved approximately 4,095 participants. The Framingham Heart Study is joint project of the National Heart, Lung and Blood Institute and Boston University.

Over the years, careful monitoring of the Framingham Study population has led to the identification of the major CVD risk factors -- high blood pressure, high blood cholesterol, smoking, obesity, diabetes, and physical inactivity -- as well as a great deal of valuable information on the effects of related factors such as blood triglyceride and HDL cholesterol levels, age, gender, and psychosocial issues. Although the Framingham cohort is primarily white, the importance of the major CVD risk factors identified in this group have been shown in other studies to apply almost universally among racial and ethnic groups, even though the patterns of distribution may vary from group to group. In the past half century, the study has produced approximately 1,200 articles in leading medical journals. The concept of CVD risk factors has become an integral part of the modern medical curriculum and has led to the development of effective treatment and preventive strategies in clinical practice.

The Framingham Heart Study continues to make important scientific contributions by enhancing its research capabilities and capitalizing on its inherent resources. New diagnostic technologies, such as echocardiography (an ultrasound examination of the heart), carotid artery ultrasound, magnetic resonance imaging of the heart and brain, CT scans of the heart and its vessels and bone densitometry (for monitoring osteoporosis), have been integrated into past and ongoing protocols.

While pursuing the study's established research goals, the NHLBI and the Framingham investigators are expanding their research into other areas such as the role of genetic factors in CVD. One project under way will produce immortalized cell lines from surviving original participants and members of the offspring study. Framingham investigators also collaborate with leading researchers from around the country and throughout the world on projects in stroke and dementia, osteoporosis and arthritis, nutrition, diabetes, eye diseases, hearing disorders, lung diseases, and genetic patterns of common diseases.

The unflagging commitment of the research participants in the NHLBI Framingham Heart Study has made more than a half century of research success possible. The study continues with an ambitious research agenda and looks forward to new discoveries in the decades to come.