Heart of the matter
How the Framingham cardiovascular study, and its small army of physicians, transformed
medical research
By Kenneth M. Ludmerer | March 6, 2005 (The Boston Globe)
A Change of Heart: How the People of Framingham, Massachusetts, Helped Unravel the Mysteries
of Cardiovascular Disease
By Daniel Levy and Susan Brink
Knopf, 272 pp
Today it is common knowledge that our lifestyle influences our health. The things that put us at risk
for heart disease -- high blood pressure, elevated blood cholesterol, cigarette smoking, excess
weight, stress, and inadequate physical exercise -- have become so ingrained in the American
psyche that it is difficult to remember a time when these risk factors were not known. Yet just after
World War II these factors went unsuspected, and they might have remained so if not for the
Framingham Heart Study, arguably the most ambitious and important long-term epidemiological
study ever undertaken.
In the late 1940s, cardiovascular disease was considered the ''silent killer." Few physicians thought
to relate heart disease to American's increasingly sedentary lifestyle or to their rich, abundant diet.
Nor did doctors worry about high blood pressure or cigarette smoking, a habit of nearly two-thirds of
adult Americans at that time. Indeed, doctors themselves smoked more than any other occupational
group.
In 1948, the US Public Health Service commissioned a long-term observational study to determine
the causes of heart disease. Framingham, where the residents overate, smoked, and suffered heart
attacks and strokes on a par with the rest of America, was chosen as the site of the study, and
5,209 residents agreed to undergo thorough physical examinations, a battery of laboratory studies,
and detailed interviews concerning their behavior every two years. This was the first time that
epidemiology -- the study of diseases in a population -- was used in a systematic, large-scale way
to investigate a chronic disease, as opposed to an acute infectious disease such as cholera or
syphilis.
The study faced numerous problems at the outset. The project's leadership initially waffled between
research and direct patient care as the goal before ultimately deciding on research. Physicians in
the Framingham area were lukewarm, fearing the study would steal their patients. Many scientists
at the National Institutes of Health thought that the government's money should be spent on the
laboratory investigation of cardiovascular disease, not on an epidemiological study. Citizens of
Framingham had substantial misgivings, until civic pride, the lure of free examinations, and an
ironclad promise of confidentiality prevailed.
The most formidable obstacles that Framingham scientists faced were intellectual. The traditional
methods of infectious-disease epidemiology -- tracing contacts and poring over death certificates -did not work for a chronic, noninfectious condition like heart disease. Large numbers of patients had
to be assembled and followed prospectively over an extended period. Dozens of possible factors
had to be identified as possible causes and controlled for. A small army of physicians and
assistants needed to be persuaded to obtain, interpret, and record data in the same way. New
statistical methods had to be invented to analyze the results.
Nevertheless, these problems were overcome, and the study succeeded. Numerous risk factors for
cardiovascular disease were identified (Framingham scientists introduced the term ''risk factor" into
medicine), and the focus of cardiology expanded to include the prevention as well as the treatment
of heart disease. The study discovered that ''average" cholesterol, blood pressure, and weight in an
overfed, sedentary society can be lethal. In the late 1960s, in the face of federal budgetary
pressures and the ongoing criticisms of some laboratory scientists, who continued to argue that
money would be better spent on experimental rather than epidemiological studies, the study almost
ended. However, supporters of the study came to the rescue, and in 1971 a new partnership with
Boston University was forged. The study has continued uninterrupted through the present.
This account of the Framingham Study, written by Daniel Levy, MD, the current director of the
study, and Susan Brink, a journalist, does justice to the courage and commitment of both the
medical scientists and the patients who contributed so much to advancing the field of cardiology.
Based upon numerous interviews, records from the study, and the director's personal knowledge of
events and personalities, the book provides a vivid portrait of the day-to-day life of the study.
The book is at its best in delineating the study's contributions to preventive cardiology, particularly
its discovery that there is a vast difference between an average and a desirable state of health.
However, the book is weak in providing the how and why of what happened and in developing an
intellectual context. Few secondary studies are cited, and many works that might have enriched the
analysis are conspicuous for their absence, most notably William Rothstein's ''Public Health and the
Risk Factor."
Probably for this reason, one of the study's most notable and lasting contributions is barely
mentioned. The Framingham Study, together with pioneering epidemiological studies in the 1950s
on the health hazards of cigarette smoking, created a new way for medical researchers to establish
the cause of a disease. At the time the Framingham Study began, the ''gold standard" for proving
that a certain factor caused a disease was through laboratory experimentation. (Witness the hostility
of experimental scientists to the Framingham Study at its inception, and the efforts of some
laboratory scientists to torpedo the study as late as the late 1960s.) The Framingham and cigarette
studies demonstrated that epidemiological methods offered an alternative, valid approach to
identifying the causes of chronic diseases. Not only did the Framingham Study determine the risk
factors for heart disease, but it established new methods that could be effectively generalized to the
study of other chronic diseases as well. The science of chronic disease epidemiology, as we know it
today, grew out of this work.
Preventive cardiology, as Levy and Brink effectively point out, was the Framingham Study's
contribution to the world. Of course, knowing that we should eat less, exercise more, refrain from
smoking, and take our medicines does not guarantee that we will do so. Maintaining a healthy
lifestyle today is not necessarily easy or fun. Nevertheless, thanks to the great work of the
Framingham Study, we now know enough to at least feel guilty about what we are not doing.
Kenneth M. Ludmerer, MD, is professor of medicine and professor of history at Washington
University, in St. Louis.
© Copyright 2005 Globe Newspaper Company.