Coronary artery calcium guides statin use eligibility

A recent study suggests the clinical value of coronary artery calcium (CAC) when statin treatment decisions are uncertain, especially among individuals with borderline predicted risk.

The analysis included 5,698 participants (mean age 61.5 years, 52.8 percent female) from the Multi-Ethnic Study of Atherosclerosis, who were grouped based on statin eligibility: statin recommended, considered, and not recommended.

The investigators also classified participants with a low-density lipoprotein cholesterol 70‒189 mg/dL without diabetes by 10-year PREVENT atherosclerotic cardiovascular disease (ASCVD) risk categories: <3 percent (low risk), 3 percent to <5 percent (borderline risk), 5 percent to <10 percent (intermediate risk), and ≥10 percent (high risk).

Finally, incidence rates per 1,000 person-years were calculated across CAC strata within statin eligibility groups and PREVENT-ASCVD risk categories.

Of the participants, 1,924 (33.8 percent) were not recommended to use statins, 897 (15.7 percent) were considered to use statins, and 2,877 (50.5 percent) were recommended to use statins.

The event rates per 1,000 person-years in those without CAC were 1.2 in the not recommended group, 2.7 in the considered group, and 5.8 in the recommended group. In participants with CAC >0, the corresponding event rates were 4.5, 5.2, and 16.6.

In participants with CAC 0 vs CAC >0, the event rates per 1,000 person-years were 1.1 and 3.0 for 10-year PREVENT-ASCVD risk <3 percent, 2.7 and 5.2 for 10-year PREVENT-ASCVD risk 3 percent to <5 percent, and 5.9 and 11.3 for 10-year PREVENT-ASCVD risk 5 percent to <10 percent, and 6.2 and 20.9 for 10-year PREVENT-ASCVD risk ≥10 percent.

“Among participants who already met guideline-based treatment thresholds, observed ASCVD event rates remained elevated even when CAC was absent, suggesting that CAC 0 should not generally be used to withhold statin therapy in these individuals,” the investigators said.

“These findings support a guideline-centred role for CAC in the PREVENT era: refining risk near treatment thresholds, contextualizing absolute risk, and informing the intensity of preventive efforts,” they added.