Cholesterol-lowering drugs may reduce the risk of heart attack and stroke in millions of people with ordinary cholesterol levels but signs of inflammation in the bloodstream, a study found.
The findings suggest that an old test for one sign of inflammation could give doctors a new way to tell which people might benefit from taking cholesterol-lowering drugs known as statins.
Half of all heart attack patients have normal cholesterol levels. A blood test can detect high levels of C-reactive protein _ a sign of inflammation.
If the findings are confirmed, statins could help 20 million to 25 million Americans who do not fit current treatment guidelines, said Dr. Paul M. Ridker, who led the study.
Ridker, a cardiologist at Brigham and Women's Hospital and an associate professor at Harvard Medical School, gets some research money from the hospital's patents on use of inflammation markers in heart disease.
Statins block an enzyme needed to make cholesterol in the liver. They also reduce levels of C-reactive protein, or CRP.
To see whether that second effect might also help avert heart attacks, researchers looked at CRP and cholesterol levels in blood samples taken from 5,742 patients during a five-year study completed in 1998.
The samples were taken at the start of the study and after a year on either a statin or a placebo.
Patients who started with CRP levels above the group's midpoint and who got the drug were at least 40 percent less likely to have heart attacks or strokes than those who got placebos _ no matter what their cholesterol levels were.
``The drugs are turning out to be a real two-for-one,'' said Ridker, whose study was published in Thursday's New England Journal of Medicine.
However, he said the study must be confirmed by research designed specifically to see whether statins do indeed prevent heart attacks in people with normal cholesterol but high CRP.
I. ``Kenny'' Jialal, co-director of the lipid clinic at the University of Texas Southwestern Medical Center in Dallas, said he believes this is the first study to show that CRP levels predict heart attacks and strokes, and that lowering those levels helps avoid them.
He said it is important to make sure patients know that infections, sprains and other problems can cause inflammation and raise the level of CRP, and that statins are not the only way to reduce it. High doses of aspirin or Vitamin E have been shown to lower CRP, he said.