Framingham flip flop
If you went through the copy-paste-enlarge gyrations to be able to read the yellowed clipping taped on to the back of my Framingham study booklet you know that Dr. Kannel, the head of the Framingham study at the time, didn’t mince words about the association of serum cholesterol with heart disease. His strong statements came, strangely enough, as a ‘clarification’ to the report published under his name showing no such association.
See Dr. Kannel’s remarks in an enlarged section of the yellow clipping below.
Just in case you can’t read it, let me tell you what Dr. Kannel said.
A number of blood lipids have been implicated in coronary disease, but none more substantially than the blood cholesterol content. That blood cholesterol is somehow intimately related to coronary atherosclerosis in no longer subject to reasonable doubt…[my italics]
Now contrast this statement by the Director of the Framingham Heart Study at the time of the yellow clipping (1970) to the following statement by his successor, Dr. William P. Castelli:
Most of what we know about the effects of diet factors, particularly the saturation of fat and cholesterol , on serum lipid parameters derives from metabolic ward-type studies. Alas, such findings, within a cohort studied over time have been disappointing, indeed the findings have been contradictory. For example, in Framingham, Mass, the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower the person’s serum cholesterol.
Hmmm. Was Dr. Castelli drunk or on dope when he said this? And he didn’t say it. He wrote it in an article published in the prestigious Archives of Internal Medicine in 1992 when Dr. Castelli was the head of the entire Framingham operation. A little different from the above quote from Dr. Kannel based on the same data.
A curious thing about this quote is his use of the word ‘disappointing.’ In science, one is supposed to be searching for the truth, not trying to prove a bias. How can scientific data be disappointing unless they don’t conform to one’s preconceived notion?
And it just gets curiouser and curiouser.
Recently Dr. Kannel was one of three authors of a paper published in the American Journal of Cardiology discussing the search for the lab test of blood lipids that would prove the most sensitive as a risk factor for coronary heart disease (CHD). Presumably, since Dr. Kannel’s name is on the paper, he approved and agreed with what was written, which is indeed interesting in view of his statement 36 years ago in the yellowed clipping.
The thrust of the paper is that the best indicators of increased risk for CHD are elevated total cholesterol/HDL cholesterol and/or elevated LDL cholesterol/HDL cholesterol ratios. What the paper has to say about total cholesterol levels and LDL cholesterol levels is indeed illuminating.
Because of a continuous graded influence of total and LDL cholesterol on coronary heart disease (CHD) development, and a substantial overlap of the distributions of the lipids in cases and noncases, it is not possible to select a critical lipid value that separates potential CHD candidates from the rest of the population. The lack of a clear demarcation of high-risk coronary candidates based solely on LDL cholesterol values indicates the need to consider dyslipidemic risk in the context of the associated lipids and the burden of other risk factors.
What Dr. Kannel is now saying 36 years later is that it is not possible to select a total cholesterol or LDL cholesterol value that separates those who are at risk for CHD. In other words, there is no point at which total cholesterol or LDL cholesterol levels tell who will or won’t develop heart disease. Now go back and look at what Dr. Kannel said in the yellowed clipping. Quite the change, I would say. And he was so sure back then. It looks like his own data back in the 1960s confirms what he is finally coming around to admit today.
But, he isn’t just rolling over. No way.
He and his co-authors are futzing with the data to figure some way to salvage their unwavering belief that somehow blood fats are involved in the development of heart disease.
What did they come up with? A few more excerpts:
At any specified total/HDL ratio level, only a suggestion of an influence of the total or LDL cholesterol level was discernible and was more evident in women than in men.
However, at low ratios, there appeared to be no discernible influence of either total or LDL cholesterol.
The total/HDL ratio appeared to predict CHD equally well at low and high total cholesterol values.
It appears that when the total/HDL or LDL/HDL cholesterol ratio is favorable, the level of the lipids that compose the ratio on CHD risk has little influence.
What does it all mean. According to the new, less authoritative Dr. Kannel and partners total cholesterol levels and LDL levels don’t mean squat as long as the ratios of total cholesterol/HDL or LDL/HDL are low. Which, means, of course, that it is HDL that matters because a high HDL reduces the ratio.
Let’s take this analysis a step further. What drives HDL up? A few things. Exercise. Alcohol in moderation. And–drum roll, please–fat in the diet, particularly saturated fat. So, I’ll leave you to draw your own conclusions.
One of the crushing blows to proponents of low-fat dieting has been the realization that although reducing fat in the diet typically reduces LDL levels a little, it reduces HDL levels a lot, leading to higher ratios. The second blow came when it was discovered that the lower LDL levels generated by the low-fat diet were composed of many more small, dense LDL particles, the very ones believed to cause heart disease.
Now comes the rechristened Dr. Kannel telling us it doesn’t matter a flip what our LDL levels are as long as we have low ratios.
In reading and authorizing comments to be published on this blog over the past year I can’t tell you how many people have written telling me that their doctors want to put them on statins because of elevated cholesterol or elevated LDL levels when their HDL levels are extremely high. I guess most doctors have been brainwashed that a total cholesterol over 200 or an LDL cholesterol over 120 is in need of treatment no matter what. This paper should put that idea to rest. Problem is, will they read it?
All these docs writing all the statin prescriptions for nothing more than elevated cholesterol or LDL levels need to do the John Kerry and flip flop the way Dr. Kannel did. At least they won’t be putting people with HDL cholesterol levels of 100 at risk for liver disease, muscle pains, and rhabdomyolisis. Let’s hope they figure it out.