Association of statin therapy with progression of coronary artery calcium composition and density on noncontrast computed tomography

The long-term effect of statins on progression of coronary artery calcium (CAC) density as measured by noncontrast computed tomography (CT) remains unknown.

We sought to examine the association of statin therapy with temporal changes in compositional calcium density using quantitative assessment of serial CAC scoring CT.

This was a retrospective, single-center study of asymptomatic individuals with serial CAC scoring CT ≥12 months apart. Scans were analyzed using a fully automated deep learning model, with quantification of per-patient total CAC volume and volumes of calcium compositional subtypes stratified by Hounsfield unit (HU) density: 130-199; 200-299; 300-399; ≥400 HU.

Of 316 patients (58.4±10.1 years of age; 49.1% men) with CAC present at baseline and rescanned at a mean interval of 3.8±1.7 years, 175 (55.4%) patients were statin-treated and 141 (44.6%) patients were statin-naive. In patients exhibiting only low-density calcium (130-199 HU) at baseline, statin therapy was associated with a temporal decrease in CAC volume (β –0.05 [–0.09 to –0.02]; p<0.05). Among patients with ≥2 calcium compositional subtypes at baseline, statin therapy was associated with a greater temporal increase in the volumes of each density stratum (130-199 HU: β 0.05 [0.00-0.11]; 200-299 HU: β 0.11 [0.07-0.14]; 300-399 HU: β 0.11 [0.07-0.16]; ≥400 HU: β 0.11 [0.06-0.16]; all p<0.05) compared with no statin therapy. Similar results were observed for changes in the relative proportions of each density stratum (all p<0.001). Statin therapy was associated with an increase in mean and peak calcium HU density (β 5.93 [4.33-7.54] and β 19.22 [12.04-26.40], respectively; both p<0.01). The effect of statins on compositional CAC volume progression did not differ between patients with baseline CAC score 1-99 or ≥100.

In asymptomatic individuals undergoing serial CAC scoring CT, statin therapy was associated with a shift toward denser calcium; considered a more stable phenotype. Assessment of CAC density may capture more unique aspects of plaque progression beyond traditional scoring.

Change in compositional CAC proportions