Protein Level Predicts Elderly Heart Disease

A blood test can help identify an elderly person’s risk of having a heart attack within the next 10 years, scientists reported recently in an American Heart Association journal called Circulation.

Researchers found that an elevated level of “C-reactive” protein (CRP)-a blood-marker for inflammation – is an independent risk factor for the development of heart disease in the elderly.

“The CRP test can provide useful information beyond standard risk assessment in the elderly,” says the study’s lead author, Dr. Mary Cushman, an associate professor of medicine at the University of Vermont, in Burlington.

Cushman says this is the first long-term prospective study assessing CRP and heart attack risk in the elderly. Short-term studies among the elderly have produced conflicting results.

The latest study followed nearly 4,000 men and women 65 years old or older who participated in the Cardiovascular Health Study, an observational study investigating risk factors for heart disease in the elderly.

Participants underwent baseline tests to determine blood CRP levels. Twenty-six percent had elevated levels, defined as values of greater than 3 milligrams per liter (mg/L).

During 10 years of follow-up, 547 of those participants had a heart attack or died from coronary heart disease.

“Elderly men and women who had elevated blood CRP had a 45 percent increase in their risk of developing coronary heart disease,” Cushman says.

Researchers also compared the CRP measurements to information gleaned from a conventional gauge called the Framingham risk score.

The Framingham risk score assigns point values to risk factors such as high blood pressure, total cholesterol, HDL or “good” cholesterol, age, and smoking history to predict the risk of a heart attack or coronary death during the next 10 years.

In men predicted to have a 10 percent to 20 percent chance, or moderate risk, of having a coronary “event” over the next 10 years based on the Framingham score alone, those with high CRP levels had in an actual observed rate of 32 percent.

The rate was 17 percent for those with low CRP levels (less than 1 mg/L).

And for men in whom the Framingham score predicted a greater than 20 percent chance, or high risk, of having a coronary event, the actual rate in those with elevated CRP was 41 percent.

The rate was 23 percent for those with low CRP levels.

Among women with a predicted rate of greater than 20 percent in 10 years based on the Framingham score, those with high CRP levels actually had about a 31 percent chance of having a heart attack or dying of heart disease.

If their CRP level was low, their actual risk of a coronary event was only 16 percent.

“The findings add information to the growing body of evidence on the usefulness of CRP measurements in assessing cardiovascular disease risk,” Cushman says.

Copyright Northwest Business Press Inc. Jul 14, 2005