Traditional risk identification with the Framingham Risk Estimate fails to identify roughly one third of women who are likely to develop coronary heart disease, according to an article published online December 16th by the American Heart Journal.

“Our best means of preventing coronary heart disease is to identify those most likely to develop the condition, and intervene with lifestyle changes and drug treatment before symptoms start to appear,” said senior author Roger Blumenthal, MD. “The goal is to strongly consider therapies, such as aspirin, cholesterol-lowering medications and, possibly, blood pressure medications for individuals at higher risk, so that heart attacks will be less likely to occur in the future.”

The Framingham Risk Estimate is a total risk stratification of how likely a person is to suffer a fatal or nonfatal myocardial infarction within 10 years, and it is based on a summary estimate of major risk factors for coronary heart disease, such as age, blood pressure, blood cholesterol levels, and smoking.

However, Blumenthal said, many women with cardiovascular problems go undetected despite use of the Framingham score. While the death rate for men from cardiovascular disease has steadily declined over the last 20 years, the rate has remained relatively the same for women.

In the current study, the American researchers examined the risk of premature
coronary heart disease in women whose average age was 50 years and who were participating in the Sibling and Family Heart Study, a long-term study of how heart disease develops among family members. Study subjects had no symptoms of heart disease, but had a sibling who had been hospitalized for a coronary event such as a myocardial infarction before age 60 years.

The researchers calculated each woman’s Framingham score and found that 98 percent were gauged to be at very low risk for future coronary heart disease, with an estimate score of less than 6 percent, while only 2 percent were judged to be at intermediate risk, with an estimate score between 10 percent and 20 percent.

When the results were contrasted with evidence gleaned from computed tomography measurements of calcium build-up in the arteries, the researchers found that one third of women originally classified as very low risk actually had coronary atherosclerosis. Indeed, 12 percent of women in the study had advanced stages of atherosclerosis, while another 6 percent had severe calcification.

“We wanted to verify if the Framingham score truly captured who was most at risk, but it turns out to have underestimated a large number of those who should be considered for preventive therapies,” noted Blumenthal.

To better determine who should get scanned, even if they have a low risk assessment, the team began to search for additional predictors of who was most at risk. They found that people with two or more risk factors, such as obesity, smoking, or metabolic syndrome, plus a family history for heart disease, were those most likely to have a high calcium score.

It is this group, the researchers said, who should be considered for a fast cardiac computed tomography scan regardless of low Framingham scores and if the physician or patient is unsure about the need to initiate long-term preventive therapies.

“For some women, especially those with a family history of heart disease and
multiple risk factors for it, additional screening using CT scan and calcium scoring may be warranted,” Erin Michos, MD, lead author, said.