For years, doctors have believed that statin therapy lowers the risk of heart disease solely by lowering levels of cholesterol.
Now, researchers at Brigham and Women’s Hospital (BWH) have found that in addition to statins ability to lower cholesterol, it is also just as important that they lower C-reactive protein (CRP), a major new risk factor for heart disease marked by inflammation, through an easy, inexpensive blood test. This finding has prompted researchers to recommend that in addition to regular cholesterol checks, monitoring and managing CRP needs to be an integral part of the health strategy for patients with heart disease. Details of this research and its implications for “dual target” therapy are published in the January 6, 2005 issue of the New England Journal of Medicine.
In early 2004, results from the multi-national Pravastatin or Atorvastatin Evaluation and Infection Therapy – Thrombolysis in Myocardial Infarction (PROVE IT – TIMI 22) trial demonstrated that lowering a patient’s LDL or “bad” cholesterol to less than 70 mg per deciliter helped prevent recurrent heart attack and death. Now, for the first time, a pre-specified analysis to assess if lowering CRP leads to clinical benefit revealed that it is not enough to lower LDL cholesterol; CRP also needs to be lowered to less than two mg per liter in order to achieve the greatest clinical benefit.
According to the BWH’s Eugene Braunwald, MD, Harvard Medical School professor and chairman of the TIMI Study Group, “We now have evidence that lowering CRP is as important as lowering LDL cholesterol for patients to reduce the risk of recurrent cardiovascular events. Physicians prescribing statin therapy need to monitor CRP levels as well as cholesterol levels if they want to get the best results for their patients.”
Based on data from 3,745 patients in the PROVE IT – TIMI 22 trial who were treated with statin therapy, clinical outcomes after heart attack were linked not only to lowering LDL cholesterol, but also to lowering CRP levels. In fact, patients who had low CRP levels after statin treatment did significantly better than those with high CRP levels, regardless of the level of LDL cholesterol attained.
“These new data confirm the crucial role inflammation plays in heart disease,” said lead author, Paul M Ridker, MD of BWH. “The data also provide the first hard evidence that lowering CRP levels is associated with clinical benefits for our patients.”
In this study, CRP and LDL cholesterol levels were measured 30 days after heart attack patients began statin therapy. Researchers found that patients who had achieved the dual targets of low CRP and low LDL had the lowest rates of recurrent heart attack or death. Specifically, the recurrent event rates during 2.5 years of follow-up were: