eighty percent of obese subjects have abnormal glucose tolerance and are hypertensive, and sixty-seven percent of hypertensive subjects are both diabetic and obese.'
That ' s a pretty awe-inspiring--or more accurately-a terror-inducing cluster! Do you see yourself there? If you stand in one corner of the picture, the odds are good that-barring a nutritional change-you ' ll eventually occupy the whole image.
Kaplan ' s insight about the Deadly Quartet was probably dependent, as much modem thought about insulin is, on the work of Gerald Reaven, MD, of Stanford University. In his study of insulin, he has been pursuing the close connection between hyperinsulinism and cardiovascular risk factors with indefatigable zeal for over thirty years now. One piece of the puzzle that Reaven examined was that hypertensionwhich no serious medical theorist has ever questioned as a risk factor for both stroke and heart disease-is intimately related to hyperinsulinism. In 1989, in a major article titled " Hypertension as a Disease of Carbohydrate and Lipoprotein Metabolism," he wrote, " Patients with untreated hypertension have been shown to be resistant to insulin-stimulated glucose uptake and are both hyperinsulinemic and hypertriglyceridemic.... " Let me translate into simpler language: If you have high blood pressure, you probably also have high insulin and triglyceride levels.
In 1988, Reaven noted a clustering of risk factors for coronary artery disease, all of which were associated with high insulin levels and increased insulin resistance. 6 These included hypertension, high triglyceride levels and decreased HDL cholesterol-the kind of cholesterol that has been found to be heart protective. Reaven has dubbed this collection of risk factors Syndrome X, and the name has stuck. Medical articles refer to the syndrome, and popular health books discuss it. It ' s a buzzword now, and since its implicit message is be careful of excess carbohydrate intake, I can only be happy about that.
Triglycerides and HDL
Meanwhile, responding in part to the urgent message of Syndrome X, medical research has moved beyond the limited predictive power of total cholesterol as an indicator of who will or will not get a heart attack. Many scientists now regard high triglycerides, high LDL( bad cholesterol) and low HDL( good cholesterol) as far more potent indicators. A series of papers coming out of Germany in the early 1990s indicated that men who had the combination of high triglycerides and low HDL were six times more likely to have heart attacks than men with the opposite propensities.
A 1997 study led by Michael Gaziano, MD, of Harvard Medical School carried this relationship even further.' He investigated the heretofore ignored ratio of triglycerides to HDL and found it significant at all levels. A high ratio means a big number when triglycerides are divided by HDL level. People whose ratio was in the upper twenty-five percent were sixteen times more likely to have coronary trouble than were those in the lowest twenty-five percent. That predictive number is a striking finding for heart disease risk. William Castelli, MD, director of the famous Framingham study on heart disease, commented back in 1992, " The findings [ from his study ] swing the pendulum and show that high triglycerides can be a significant risk factor for some patients."
A study published in Circulation by a research team in Helsinki showed that those with high triglycerides plus an unfavorable LDL / HDL cholesterol ratio could lower their heart attack risk rate by seventy-one percent when these problems were corrected.
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