Doubts Emerge on the Value of Very Low Cholesterol Levels

From Scientific American:

Since 2002, when ATP III called on doctors to push LDL levels below set targets, the concept of low cholesterol has become synonymous with heart health. Patients brag about their cholesterol scores, physicians joke about adding statins to drinking water, and some hospitals reward doctors when patients hit cholesterol targets. In 2011, US doctors wrote nearly 250 million prescriptions for cholesterol-lowering drugs, creating a US$18.5-billion market, according to IMS Health, a health-care technology and information company based in Danbury, Connecticut. “The drug industry in particular is very much in favour of target-based measures,” says Joseph Drozda, a cardiologist and director of outcomes research at Mercy Health in Chesterfield, Missouri. “It drives the use of products.”

ATP III reflected a growing consensus among physicians that sharply lowering cholesterol would lessen the likelihood of heart attacks and strokes, says Richard Cooper, an epidemiologist at the Loyola University of Chicago Stritch School of Medicine in Illinois, who served on the committee that compiled the guidelines. The committee drew heavily on clinical data, but also took extrapolations from basic research and post hoc analyses of clinical trials. LDL targets were set to be “less than” specific values to send a message, Cooper says. “We didn’t want to explicitly say ‘the lower the better’ because there wasn’t evidence for that,” he says. “But everybody had the strong feeling that was the correct answer.” By contrast, the ATP IV committee has pledged to hew strictly to the science and to focus on data from randomized clinical trials, says committee chairman Neil Stone, a cardiologist at Northwestern University School of Medicine in Chicago. If so, Krumholz argues, LDL targets will be cast aside because they have never been explicitly tested. Clinical trials have shown repeatedly that statins reduce the risk of heart attack and stroke, but lowering LDL with other medications does not work as well. The benefits of statins may reflect their other effects on the body, including fighting inflammation, another risk factor for heart disease.

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