NEW YORK (Reuters Health) – Individuals with minimal or no coronary calcification face a low risk of cardiovascular events, according to results from the Multi-Ethnic Study of Atherosclerosis (MESA).
“Calcium scoring outperforms C reactive protein, lipid measures and other risk stratification techniques,” lead author Dr. Matthew J. Budoff from Harbor UCLA Medical Center, Torrance, California told Reuters Health in an email.
The 6-center study, reported in the October American Heart Journal, was designed to determine how heart disease event rates in individuals with low coronary artery calcium (CAC) Agatston scores (1 to 10) compare to those in individuals with CAC scores of zero.
Among 3923 participants, all symptom-free and without known cardiovascular disease, there were 3415 with no detectable calcification on computed tomography and 508 with CAC scores of 1 to 10.
According to the article, the event rates for nonfatal myocardial infarctions or coronary heart disease-related deaths per 1000 participants were 0.74 in the zero calcification group and 3.01 in the minimal CAC group.
Rates of coronary heart disease events per 1000 person-years at risk were 1.25 in the zero CAC group and 5.54 in the minimal CAC group.
After adjustment for age and gender, minimal CAC was associated with a 3.23-fold higher risk of nonfatal myocardial infarctions or coronary heart disease-related death and a 3.66-fold higher risk of any coronary heart disease event.
“Given their low risk status (<1/1000 chance of myocardial infarction), the best therapy” for patients with minimal CAC scores “is probably lifestyle modifications,” Dr. Budoff told Reuters Health.
“I rarely use statins in this low risk cohort,” he added.
Former or current smoking and diabetes were significant predictors of any coronary heart disease event, the researchers note, whereas cigarette smoking and internal carotid intima-media thickness tended to be associated with an increased risk of nonfatal myocardial infarctions or coronary heart disease-related death.
“The ability to directly visualize atherosclerosis gives clinicians an easy target for therapy, and perhaps more importantly, can determine the 50%-plus patients who do not need aggressive interventions due to the presence of clean coronaries,” Dr. Budoff said.
“We are going to continue follow up the MESA participants over 15 years,” he added. “We are also working on following a cohort of 4000 participants with follow up scans to see if new onset of calcification or significant progression is a marker of outcomes.”
Am Heart J 2009;158:554-561.