A Conversation With Henry Blackburn : Epidemiology

Secondary Logo

Journal Logo


A Conversation With Henry Blackburn

Harlow, Bernard L.

Author Information
Epidemiology 19(3):p 513-517, May 2008. | DOI: 10.1097/EDE.0b013e31816a9e3b


Click on the links below to access all the ArticlePlus for this article.

Please note that ArticlePlus files may launch a viewer application outside of your web browser.

Henry Blackburn was born in Miami, Florida, on March 22, 1925. Educated at the University of Miami and Tulane University School of Medicine, he was then trained at Northwestern Memorial, the American Hospital of Paris, and the University of Minnesota. He established clinics for Methodist missions in Cuba in 1949 and served as US Public Health Service (PHS) officer for the Displaced Persons Act in Austria from 1950 to 1953. He joined the faculty of the Laboratory of Physiological Hygiene at Minnesota in 1956 and conducted field surveys of the Seven Countries Study through 1972. That year he became Director of the Laboratory upon Ancel Keys's retirement, and in 1983, with the retirement of Leonard Schuman, became chairman of the Division of Epidemiology. Two signature publications initiated his career: “The electrocardiogram in population studies” (aka The Minnesota Code) and “Cardiovascular Survey Methods” with Geoffrey Rose. His work in observational studies led to participation in the design and direction of national preventive trials from the 1960s through the 1980s. In the late 1970s he proposed population-wide strategies of surveillance and preventive interventions that culminated in the Minnesota Heart Survey, which has been conducted since 1979, and the Minnesota Heart Health Program, a six-community study begun in 1980. In retirement, he is chronicling the history of cardiovascular disease epidemiology.


BH: Few people start with the intent to become an epidemiologist. Can you describe how your own path brought you to epidemiology?

HB: The path was certainly not linear. I remember vividly in medical school the visit of a missionary who told us he had worked in the Congo for 25 years and had never seen a heart attack or a case of appendicitis or tonsillitis. That really stuck with me. A couple of years later, doing medical missionary work in eastern Cuba, near where Castro was hiding in the mountains, I ran into mass disease where there was poverty, oppression, ignorance, and superstition, and realized that common diseases were largely social in origin. That was confirmed when I worked in displaced-persons camps in Austria for 3 years, helping people get into the States. The common diseases had little to do with medicine and genetics, and the conditions themselves had little response to medical ministrations. The diseases were social, cultural, political and economic in nature and genesis, and required population studies and socio-cultural strategies well beyond the medical for their understanding and prevention.

So, my experiences created a susceptibility to epidemiology and public health.

The vectors were several. Getting interested in the cardiovascular part was personal, having been rejected by a Navy recruiting doctor for a heart murmur. Who was it who said, “Facing the guillotine really focuses your mind?” Well, facing a heart murmur focused mine, but a month later it was not found, and I was in the Navy. But it surely pointed me toward cardiovascular interests.

When I got back to the States for residency training, I started work with Ernst Simonson, a German physiologist here in Minnesota and I did a thesis of rather pedestrian research on the spatial configuration of ventricular activation in the ECG. It taught me survey methods. I put on my uniform, went out to the Naval base, recruited the fellows, and examined, exercised, and measured them. It became an exercise in measurement error, repeat variability, distributions, normal and abnormal, and simple statistical tests … a marvelous preparation for later.

All this took place where Simonson had an appointment, in Ancel Keys's famous Laboratory of Physiological Hygiene under the Memorial Stadium bleachers, Stadium Gate 27. It was a very exciting place, intellectually, and on the edge, at the beginning of this romantic period in the origins of cardiovascular disease epidemiology.

At the end of residency, offered the choice of a junior faculty appointment in medicine versus working with Ancel Keys, I accepted Keys, who clearly was after the Holy Grail of lifestyle causes of the coronary epidemic. I was told by a much-annoyed head of medicine that I would never be among the elite of internal medicine in this country if I went to work with those “crazy guys, doing those weird things under the stadium.”

BH: When you think about the work you were doing under the stadium, and the epidemiology practiced then, how has it changed?

HB: How many ways it is different! Cardiovascular epidemiology at that time was not done by epidemiologists but by people who were experts passionately involved with cardiovascular function or pathology—clinicians, biochemists, physiologists, and statisticians. There were few chronic disease epidemiologists at all in midcentury, and they were mainly in respiratory disease.

There were a couple of exceptions. There were public health people who had the vision of the epidemiologic transition—that is, heart disease going up, communicable diseases going down. Joseph Mountain, was a PHS official who introduced the Framingham Heart Study in 1948. Bradford Hill and Richard Doll were beginning to look at smoking, lung cancer and heart disease. Jerry Morris was studying occupations in London. But, generally, cardiovascular epidemiology was started by people on the front lines of studying heart disease and vascular function. This was a major difference from today, and from other types of noncommunicable disease epidemiology.

Another difference is the lack of sophistication in design and methods, back then, which actually got us together, talking, sharing and creating a collegial environment. There are the differences in computation, data storage, data handling and analysis. I can still hear the clickety-clack of those Frieden mechanical calculators used in our laboratory … the loud hum when they became electrified. And I remember the PDP8 we got that had a memory—all of 4K! The next one, late 1960s, had 2 megs. So that is a major change.

There was a difference in leadership and operations; back at the beginning it was more relaxed in the production of research and finding funds. Tenure today is a major difference. Tenure completely changed the picture of epidemiology in the ′70s. Before that we had long apprenticeships under no pressure as we became gradually and comfortably more skilled, by practice and osmosis. Now, it's 6 years, up and out. So, tenure really modified the environment of the long and happy apprenticeship, with the new focus on the self, “on publish or perish” rather than on scientific issues and team roles.

Other changes are more concerning—about the medical directions in contrast to the social directions of epidemiology, and the “medicalization” of public health and prevention.

BH: What person would you single out as having most strongly influenced your career?

HB: Clearly, Ancel Keys, because he recruited me, gave me an assignment to convert clinical medicine to the needs for counting bodies and diseases in populations … right down my alley. Also, Geoffrey Rose, with whom I wrote a cardiovascular survey manual for WHO.1 And Jerry Stamler, who gave me the opportunity to work in clinical trials. So those 3 people, with Keys the central character.

BH: Collaboration is essential to successful epidemiologic studies. We're moving away from the silo approach, and more into collaborative kinds of relationships with colleagues. What have you found to be the most important ingredients of a good collaboration? And, with whom have you had your best collaborations?

HB: Common or mutual interests with someone who is nondefensive in communications are my requirements of good collaboration. The best I had early was with Suketami Tominaga at the University of Maryland trials coordinating center. We had a delightful collaboration on the predictive value of the electrocardiogram in the Coronary Drug Project. Collaborating with Geoffrey Rose on the survey manual1 was marvelous; his clarity of thinking and parsimony of language were remarkable. I remember working with Ancel Keys on a review article, and the happy moment when the editor said he couldn't tell where Keys's writing left off and mine began. I had admired Key's writing, so that thrilled me. There were great collaborations, particularly the Coronary Drug Project, which was competently done and collegially operated. In recent decades most of us in epidemiology in Minnesota have been collaboratively preoccupied with the same projects of population surveillance and community interventions. There were few loners. Collaboration is trying but generally more fun.

BH: Who would you regard as the 2 or 3 epidemiologists who you admire the most?

HB: There are so many … and for different reasons. I mention a name you might not know, James Watt. Watt was a Public Health Service officer studying diarrheal diseases and the transmission of polio. This young fellow, for whatever reason, was appointed head of the National Heart Institute in 1952, its second director and a most influential appointment in the field. He was able to establish epidemiology as an equal discipline, equal administratively and conceptually. Maybe not in funding, but firmly established in the research policy of the Heart Institute in a way that's persisted to this day. All cardiovascular epidemiology, and much of population approaches in the other NIH institutes, comes from his having established this equality. Don't think that the heads of NIH, the elites from the laboratories and from the clinics, would give epidemiology a crumb if he hadn't fixed that into administrative policy!

But, if you want me to go on from there, I defy you to distinguish between the influence of Bradford Hill and Richard Doll, Geoffrey Rose and Mervyn Susser, Jerry Stamler and Abe Lilienfeld. You should stop me there.

BH: Thinking about your contributions, what would you say was your most influential paper?

HB: Again you taunt me with the “single most important.” I'm going to throw you a story instead: Ancel Keys was invited to the first meeting of the World Health Organization to discuss arteriosclerosis and its great burden on humanity. A dozen experts from around the world were there, including Sir George Pickering of Oxford. Keys, in his usual bluntness (bombast) propounded his diet-heart theory with great vigor.

Keys was quite taken aback when Sir George Pickering asked him: “If you would please be so kind, Professor Keys, tell us the single most important piece of evidence you have to back up this diet theory of yours?”

Keys fell into the trap. He identified a piece of evidence. And of course, Sir George and the assembled experts were able to diminish that almost to dust. It was too late for Ancel to discuss the whole body of evidence necessary to create the hypothesis. He was stung; defeated by a debater's trick.

So, I would rather be remembered for a body of knowledge than for an article, and perhaps for providing an environment where people from a lot of disciplines can get together and focus on major medical and public health issues.

BH: Which manuscript do you feel most personally proud of, even though for some reason it was under the radar screen?

HB: The only thing worse than asking me which was “the most” … is asking what I was the “most proud of,” when my background doesn't allow pride. Pride is a sin, you see. “Satisfaction,” perhaps. That might be a review article, “A public health view of mass hyperlipidemia,” buried in somebody else's book.2 Another article on the origin of modern epidemic diseases, a human evolutionary legacy as hunter/gatherers, also got buried.3

The article best remembered, of course, is “The electrocardiogram in population studies,” or the Minnesota Code, that became a classic citation, meeting a topical need in early epidemiology and trials.4 It's a little disturbing that a methods paper would be the best known contribution, something that's obsolete; a simple dichotomous classification from 50 years ago. But that's the way it is.

BH: How did you choose your research questions?

HB: The methods for electrocardiography and clinical diagnosis that Ancel Keys needed for our international surveys were simply assigned to me. That's often the way. We were given a data base, or a charge, and off we went. I chose as my first research area, “Characteristics of Smokers and Non-Smokers,” because there was a grant available. You know that issue. When I was more experienced, I chose big issues of surveillance and preventive interventions, seeing the remarkable cultural differences in cardiovascular disease risk and rates—knowing that you had to measure them in a population to understand them, relate them to risk characteristics of the population, and study their trends over time. We initiated the Minnesota Heart Survey in preparation for an intervention in communities—the Minnesota Heart Health Program. Those questions came from observations in the field, not from an assignment, and surely not from funds available.

BH: What are your interests outside of epidemiology?

HB: Aside from family skiing and canoeing in younger days, and musical activities over a lifetime, a 20-year hobby has been studying human evolution and its legacy affecting our susceptibility to diseases of affluence. My most recent interest is in the history of cardiovascular disease epidemiology. I've had conversations with 100 pioneers and am composing 150 mini-biographies. I've collected several thousand references and have developed an archive of writings and correspondence from Ancel Keys, John Gofman (the nuclear scientist who became an expert with ultracentrifugal fractionation of lipoproteins), Fred Epstein, a great leader and dear friend, and Zdenek Fejfar, head of the WHO Cardiovascular Unit who gave us his precious letters and photographs shortly before he died.

Then, with your support and that of Dean Finnegan and of our school, I'm developing a CVD history Web site: “Preventing Heart Attack and Stroke.”5 Finally, I have some support from the National Library of Medicine to prepare a book on the history of research in cardiovascular disease epidemiology and prevention. These are my favorite extracurricular activities. I can assure you, historians have as much as fun as—I won't say blondes—but as biologists and epidemiologists!

BH: What do you think is the most important contribution epidemiology has made to society in your lifetime?

HB: I'd say identifying causal factors of mass diseases and of healthy populations; establishing in trials their ability to be modified; and providing the sound scientific basis for preventive practice and public health policy. That's the principal contribution of epidemiology. The secondary effect is clues it gives to mechanisms and new ideas about disease.

BH: Thinking about epidemiology today, how are we doing?

HB: Well, there's good news and bad news. Most people prefer to listen to optimists. I'm impressed by the competence of our young epidemiologists, their ability to do studies and analyses both on their own and collaboratively. The good news is that we are now, in chronic disease epidemiology, a mature profession with continuing vision, and we're oriented to do good science that directly affects the common good.

The bad news is that we have become an instrument of medical strategy. I won't wax conspiratorial here, but medical strategy focuses on the individual, and in today's culture of the individual, epidemiology has become a part. We're working on individual risk and its ultimate refinements, having turned—hopefully not forever or irretrievably—from our mission for the common good, for the health of the population and the species.

I am concerned about this intense culture of the individual over the larger good, and about epidemiology's role in that trend. The “medicalization of prevention” is a serious diversion, and we're playing a role.

BH: What are your predictions of the future for our field?

HB: There are 2 kinds of crystal-ball gazers: a kind that is able to analyze health trends and join them with political-economic trends to predict climactic events years down the line. And there are those who predict based on what we think the need is, and what we would hope for. What I would predict and hope for is that we, in epidemiology, would be turning away from this focus on the individual and mechanisms, learning as much as we can about them, but moving toward our larger role: what influences the common diseases and what causes the great burdens of society and the great epidemics, and then, what influences lead to a healthy society.

BH: What would you say is the single most important piece of advice for our newly graduating epidemiologists?

HB: My platitude is: “Do a good job of what's before you. That's the only way you get to do another job, and a better job.”

Beyond that, I advise student epidemiologists to “know thyself.” Are you an idea person and need help in organization and administration? Are you a doer, and need to spend more time thinking? Are you a methodologist, going to produce a new method that'll improve science? You need all these qualities, but you need to know what kind of person you are, and, while trying to improve in all areas, put yourself with people who complement your aptitudes.

My advice is to apprentice yourself to a good person in a strong institution. This is the best way to work through problems, to get experience, and to meet the good people in the field. So many young people go out, having done their theses on somebody else's data, and are thrown to the wolves. They've done some teaching, but they're forced to perform as principal investigators without an apprenticeship. Get with a good institution and be an apprentice as long as the economy (and your family) will allow you to be one.

BH: Is there anything else that you would like to add?

HB: I would need a soapbox. Perhaps just a bit more about “personalized medicine.”

The credo of the National Institutes of Health (NIH) is, “From the bench to the bedside.” Never do you hear, “From the bench to the bedside to the population outside.”

Whenever I hear that credo, I rise and say, “And to the population outside.” When I rotated off the advisory council at NIH (NHLBI), the Director said that, “If Henry Blackburn had his way, this would be the National Institute of Preventive Cardiology,” rather than “Heart, Lung, and Blood.” And he was right. But the NIH slogan, now, is “Personalized Medicine,” with the dream that we can identify all the individual's susceptibilities and target our therapy.

Arno Motulsky, a distinguished physician-geneticist, once said to me, “Henry, we are that far” (meaning a very small distance and this was 20 years ago) “from being able to determine by a few measurements the real susceptibility and vulnerability of an individual, so that the likes of you” (and I think he said “your ilk”) “won't have to bludgeon the public with your ideas about diet and lifestyle.”

That's the dream of “Personalized Medicine.” It's a pipe dream.

It is looking away from the phenomena that cause common diseases and epidemics. That is where I think the future of epidemiology lies, in that unexplored space between the socioeconomic and cultural component causes and the disease and health of a population. If we can identify the mechanisms for that transfer between the culture and the population, and help them be changed, we will get back to our original mission: the health of the population and the common good of all.


BERNARD L. HARLOW is the Mayo Professor of Public Health and Head of the Division of Epidemiology and Community Health at the University of Minnesota School of Public Health. His interests are in reproductive and gynecologic epidemiology. Harlow is a close associate of Henry Blackburn and a 1978 alumnus of the University of Minnesota School of Public Health, during the time when the Laboratory of Physiological Hygiene maintained its famous location under Memorial Stadium.

Henry Blackburn, 1972.
Henry Blackburn, 2007.


1. Rose GA, Blackburn H. Cardiovascular Survey Methods. Geneva: World Health Organization; 1968.
2. Blackburn H. Diet and mass hyperlipidemia: a public health view. In: Levy R, Rifkind B, Dennis B, et al, eds. Nutrition, Lipids and Coronary Heart Disease. New York: Raven Press Publishers; 1979.
3. Blackburn H. Physical activity and coronary heart disease: a brief update and population view (Parts I and II). J Cardiac Rehab. 1983;3:101–111, 171–174.
4. Blackburn H, Keys A, Simonson E, et al. The electrocardiogram in population studies. A classification system. Circulation. 1960;21:1160.
5. Preventing heart disease and stroke: a history of cardiovascular disease epidemiology. Available at: http://www.epi.umn.edu/cvdepi/index.html.

Supplemental Digital Content

© 2008 Lippincott Williams & Wilkins, Inc.