Having both a high lipoprotein(a) and high coronary artery calcium score (CAC) results in a 22% risk of heart attack or stroke over the following 10 years, nearly double the risk of having either condition alone. These are the findings are from a study published in the Journal of the American College of Cardiology (JACC).
Two decades ago, it was recognised that lipoprotein(a) (Lp(a)) concentrations were elevated in patients with cardiovascular disease (CVD). However Lp(a) was not yet proven to be important due to a lack of both Lp(a)-lowering therapy and evidence that reducing Lp(a) levels improves CVD risk. Recent research has added to the evidence
“We are hopeful that by making the connection between Lp(a) and CAC as dual risk drivers, we can raise awareness in the medical community and improve earlier heart attack prevention for these patients,” said cardiologist Parag Joshi, MD, Associate Professor of Internal Medicine at UT Southwestern. “Our data may also expedite the development of treatments designed specifically for this high-risk population.”
About one sixth of people in the U.S. have high Lp(a), driven largely by genetics. Coronary artery calcium (CAC) is a marker of plaque deposits around the heart.
Cardiology researchers confirmed the Lp(a) and CAC connection by comparing data from two landmark cardiovascular trials, the Dallas Heart Study, an ongoing comprehensive study of 6000 diverse and heart-healthy patients conducted from 2000 to present, and the Multi-Ethnic Study of Atherosclerosis (MESA) 6000-participant study investigating early-stage atherosclerosis.
The researchers found that participants with combined high Lp(a) and high CAC had a 22% 10-year risk of heart attack or stroke, compared with a 10-15% 10-year risk in patients who had either risk factor alone.
The team identified three distinct risk-related trends:
- High Lp(a), high CAC: These individuals face the highest 10-year risk of heart attack or stroke.
- High Lp(a), zero CAC: 10-year heart attack and stroke risk is low when there is no CAC, even if Lp(a) is high.
- Low Lp(a), high CAC: 10-year heart attack or stroke risk is higher than average but lower than with high LP(a) and high CAC combined.
“Establishing the connection between Lp(a) and CAC means we can move to the important next phase of research, which will be defining and personalizing early screening protocols to identify patients at high risk of heart attack,” said Dr Joshi. “With further research, this could mean selectively scanning patients with high Lp(a) for their CAC score, and studying therapies specifically designed to reduce Lp(a) among patients with high CAC.”
Source: UT Southwestern Medical Center
