Cardiovascular risk assessment can rely heavily on coronary artery calcium (CAC) scoring. However, its added value in ruling out obstructive coronary artery disease (CAD) might well depend on age, based on a large observational study published in late October 2021 in JAMA Cardiology.
This cohort study obtained data from the Western Denmark Heart Registry and had a median follow-up time of 4.3 years. Included patients were aged 18 years or older who underwent computed tomography angiography (CTA) between January 1, 2008, and December 31, 2017, because of symptoms that were suggestive of CAD.
A total of 23 759 symptomatic patients, of whom 12 771 (54%) had a CAC score of 0, were included. This cohort had a median (IQR) age of 58 (49-65) years and was primarily composed of women (13 160 [55%]). Overall, the prevalence of obstructive CAD was relatively low across all age groups, ranging from 3% (39 of 1278 patients) in those who were younger than 40 years to 8% (52 of 619) among those who were 70 years or older. In patients with obstructive CAD, 14% (725 of 5043) had a CAC score of 0, and the prevalence varied across age groups from 58% (39 of 68) among those who were younger than 40 years, 34% (192 of 562) among those aged 40 to 49 years, 18% (268 of 1486) among those aged 50 to 59 years, 9% (174 of 1963) among those aged 60 to 69 years, to 5% (52 of 964) among those who were 70 years or older. The added diagnostic value of a CAC score of 0 decreased at a younger age. Of note, the presence of obstructive vs nonobstructive CAD among those with a CAC score of 0 was associated with a multivariable adjusted hazard ratio of 1.80 (95% CI, 1.02-3.19) for myocardial infarction and all-cause death in those who were younger than 60 years.
Reference: https://jamanetwork.com/journals/jamacardiology/article-abstract/2785586