By any measure, heart disease, once manifest by sudden death, has largely joined the ranks of chronic diseases in developed countries that can be managed by drugs and behavior, as several articles in the new January-February issue of Health Affairs devoted to Cardiovascular Disease & Society note. And of all diseases that have been long-studied by NIH-supported research, progress in treating and preventing heart disease is at the top of the list of successes. Striking surgical intervention, even heart transplantation, has saved countless lives during the past three decades. Better still, fundamental understanding of the biological events that predispose adults to heart attacks, such as hypertension, high concentrations of lipids in the blood, and too little of the “good” low density lipoproteins, have done what research is supposed to do: laboratory studies have moved into ordinary clinical medicine in a major way. In 1988, the cholesterol-lowering statins — now advertised daily on television — were a new class of drugs. Today they are prescribed for millions.

There is little doubt that statins lower cholesterol and, for now, it seems prudent to use them for heart disease prevention. Low blood pressure is important. So is low cholesterol. But as NIH director Elias Zerhouni observed in a recent conversation with me, “high cholesterol does not cause heart disease.” Rather, it contributes to it. We know a lot about substances that negatively affect the cardiovascular system, but we still don’t know enough.

”Over the past 35 years, U.S. age-adjusted mortality from cardiovascular disease declined 50 percent,” note Myron L. Weisfeldt and Suzan Zeiman of Johns Hopkins. Nevertheless, in the United States alone, 350,000 men and women who seem to be “just fine” drop dead of a heart attack every year.

And there is plenty of evidence that the cost of turning heart problems from a lethal disease to a chronic one is costly. Harvard economist David Cutler says the use of drugs, particularly for hypertension, is worth the cost. Thomas Pearson of the University of Rochester has a slightly modulated take on the situation. “We’re doing better,” he said at a press briefing Health Affairs held on its cardiovascular disease issue, ”but as the baby boomers age, the incidence of heart disease will double. Just turning this into a chronic disease is not the answer.”

Learning from genetics. Here is where so-called “personalized medicine” may come to play an important role, for both prevention and treatment. A year ago the National Heart, Lung, and Blood Institute (NHLBI) launched what is calls the “Framingham Genetic Research Study,” part of the Institute’s 59 year old study of the ordinary citizens of Framingham, Massachusetts (and their offspring). This is among the first of the big time studies of a large number of families who have agreed to let NIH researchers track their health from birth to death. Adding genetics and heart disease is an extremely important step in the right direction.

The human genome contains a number of genes—perhaps 30 or more—that are thought to be “associated” with the eventual development of one form of heart disease or another, and if the hypothesis is correct, it will likely turn out that different combinations of genes are associated with different forms of heart disorders. At the Health Affairs press briefing, NHLBI director Elizabeth G. Nabel enthusiastically reported that some 9,000 men and women, across three generations, are part of this study that will record approximately 500,000 analyses of their DNA, trying to get a handle on just what those genes do, and when they do it.

“We hope to have data about the phenotypes (or physical characteristics) of the study participants by the end of the year,” Nabel said. Even though “genetic associations” do not necessarily mean much for individuals, these data, linked to the DNA analyses, will be a goldmine for research. And that, in turn, could produce genetic profiles that do apply to you or me. Nabel, an optimist, predicts that data can be used by real doctors for real patients within the next five years if everything falls into place.

For example, Zerhouni notes that, even though statins benefit only a small portion of those at risk for heart disease, we give them to everyone at risk for heart disease because we can’t know in advance who the few who will benefit will be. Genetic profiles could allow physicians to target statins and other drugs to only those who will benefit, saving other patients and society from unnecessary expense and side effects. And personalized information could be just what it takes to help motivate people to work determinedly to prevent disease before it occurs.

If research leads to prevention, and the need for expensive and sometimes debilitating treatment is reduced, it does not mean that cardiovascular disease will vanish. But it might mean that it can be postponed to the late decades of life. Throughout the Iliad, Homer spoke more than once about death because the “old man’s heart failed him.” If that were the routinely the only time when heart disease claimed a life, research will indeed have accomplished what it has set out to do.

This entry was posted on Monday, January 29th, 2007 at 6:52 pm and is filed under All Categories, Chronic Care, Pharma. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.