Women typically considered at “low risk” for heart disease and cardiovascular disease events (heart attacks, heart pain, stroke) may actually be at high risk if they exhibit coronary artery calcium (CAC).
Testing for CAC is not part of the standard Framingham risk score (FRS), which is given to estimate the 10-year risk for coronary heart disease (CHD) and Cardiovascular Disease (CVD). “Low risk” is considered to be a risk of less than 10% risk of developing CHD or CVD within the next 10 years.
A study of 2,684 “low risk” women, below the age of 79 and without diabetes (which leads to other complications), was conducted to test the correlation of CAC with CHD and CVD. The age range was 45 to 78 years old, with a mean age of 60 years of age.
Of the 2,684 women, 32% had a detectable presence of CAC, and 4% had a statistically “high” score (a CAC score of 300 or higher).
Over a 3.75 year span, 34 “low risk” women had CVD events, such as stroke. Over the 3.75 year span, 24 “low risk” women had CHD events, such as heart attacks and heart pain.
According to the study, headed by Dr. Susan G. Lakoski of the Wake Forest School of Medicine, “There was a 6-fold greater risk for a CHD event in women with prevalent CAC compared with women with no detectable coronary calcium,” and “there was a 5-fold greater risk of a CVD event in women with prevalent CAC compared with those with no detectable CAC.”
The study showed that a large percentage (32%) of women labeled as “low risk” by the FRS had a detectable level of CAC, and CAC was shown to greatly increase the risk of CHD and CVD events. The suggestion of the study, based on these conclusions, is that CAC screening may be warranted in addition to the FRS for women being tested for present and future CHD and CVD.
Source: Defeat Diabetes Foundation: Lakoski, Susan. Greenland, Philip. Wong, Nathan, et al. Archives of Internal Medicine. “Coronary Artery Calcium Scores and Risk for Cardiovascular Events in Women Classified as “Low Risk” Based on Framingham Risk Score.” December 2007.