Junkfood Science: How about that score?

July 10, 2007

How about that score?

From the “Studies the media forgot” file, come two new studies in the current issue of the American Heart Journal which examine the ability of traditional heart disease risk scores to estimate actual risks for heart disease and premature death among young and old men.

These studies looked at the most favored assessment tool — the Framingham risk score — commonly believed to predict the chances among healthy people for later developing heart disease and premature death. It uses the conventional risk factors blood “cholesterol” levels, blood pressure, smoking status, age and gender. As we’ve seen, the most popular risk factors don’t predict heart disease or premature death for most people, notably women, children and adolescents.

The first study, conducted by researchers at the Feinberg School of Medicine in Chicago, IL, tested the Framingham risk score, as well as the similar online ATP III risk estimator, to predict heart disease deaths among 10,551 young men 18-39 years of age. After 10, 20, and 30 years of followup, both risk factor tools failed to predict risks among young men, even those who proved to later be at the highest actual risk.

The second study was led by Dr. Michael T. Koller, M.D., at the Basel Institute for Clinical Epidemiology in Basel, Switzerland. These researchers examined the accuracy of the Framingham risk score when used among nearly 6,800 people in the Netherlands, 55 years of age and older. After ten years, they found that the Framingham score overestimated the mature men’s risks, resulting in a substantial number of false-positive scores, with a specificity of 70%. Among the mature women, the Framingham score failed, with a grade of 33%, and only predicted heart disease in one-third of the women.

The Framingham Heart Study was begun back in the 1940s in Framingham, Massachusetts, under the direction of (what is now called) the National Heart, Lung, and Blood Institute (NHLBI). Its goal was to identify the commonalities (correlations) among a large group of healthy people who later developed heart disease and died prematurely. It found that while our parental genes are the biggest determinants of how long we’ll live, age is still the most significant risk factor for dying.

The Framingham Heart Study also actually showed that people whose cholesterol levels were lowered were at a 14% increased risk of death from heart disease for every 1mg/dl, said Dr. Malcolm Kendrick in The Great Cholesterol Con. Even the major pan-European study called EUROASPIRE, which looks at risk factors for heart disease across Europe, has reported that obesity, raised blood pressure, elevated total cholesterol and low HDL cholesterol were not significantly associated with higher mortality rates, despite low usage of drugs to lower blood pressure and blood lipids, he said.

Despite the Framingham Heart Study findings, the popular Framingham risk score emerged, with cholesterol the focus. It is now recommended by the government’s National Cholesterol Education Program launched by the NHLBI under the U.S. Department of Health and Human Services. The American Heart Association also recommends the Framingham risk score in its preventive guidelines for the management of cholesterol levels and the prescribing of statins, as does the National Institute for Health and Clinical Excellence (NICE) in UK. NICE recently made it mandatory in its new practice guidelines for doctors, and all adults with a 20% or greater score are to be prescribed statins. It will put an estimated 14 million people in the UK on statins.

Yet, “high cholesterol levels don’t cause heart disease,” explained Dr. Malcolm Kendrick, Medical Director of Adelphi Lifelong Learning, Cheshire, UK, and long-time cholesterol researcher. “Statins seem to lower cholesterol, but then no one has proven that this is what reduces the risk of heart disease,” said Dr Kendrick. The evidence demonstrates that statins increase lifespans minimally among men. But “if you’re a women? No extra months, weeks, days or hours. Statins are absolutely pointless.” Even a major clinical trial of high risk men with heart disease who’d had a heart attack, by taking statins for five years they had a 96.8% chance of being alive, compared to 95.9% among those taking a sugar pill.

But more importantly, regular statin use puts patients at risk for side effects, some potentially fatal. “If you give statins to anyone they will suffer minor muscle damage,” Dr Kendrick told the Telegraph last week. “But it is the elderly and frail who are affected significantly. In my own patients, I have found muscle damage to be a common side effect, which manifests as muscle pains and weakness.” These patients can develop rhabdomyolysis, a muscle wasting that can lead to kidney failure, as well as cognitive problems. According to the FDA, there have been 416 deaths between 1997 and 2004 directly attributable to simvastatin (Zocor) alone, he said.

A poignant editorial was included in this same issue of the American Health Journal by the editors, Dr. Daniel B. Mark, M.D., MPH, Patricia Hodgson, BA, and Robert M. Califf, M.D. They explained what they publish in the Journal and why, saying:

The danger of publication bias is now well-recognized. We continue to feel that publication of these data is an important service that we intend to continue.... [N]egative outcome studies that seem to go against prevailing wisdom often have great difficulty getting published. Failure to get these data into the public domain means that the process of correcting prevailing wisdom may be slowed significantly.To be competitive for publication [in the AHJ], such papers will need to demonstrate access to high-quality empirical data (where applicable) and state-of-the-art methods and analysis.

Imagine if more publications were devoted to reporting only the highest quality evidence, even if it countered popular beliefs and clinical practices. The quality of healthcare could only improve and more lives saved.

© 2007 Sandy Szwarc

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