Abstract
BACKGROUND: Recent guidelines suggest that coronary computed tomography angiography (CTA) may be the preferred testing modality in patients <65 years of age who are suspected of having coronary artery disease (CAD). Because of a higher prevalence of CAD, the role of coronary CTA in older cohorts is less well established. OBJECTIVES: The authors aimed to characterize the yield and prognostic utility of coronary CTA by age in a large registry with long-term follow-up. METHODS: Retrospective cohort of patients clinically referred to coronary CTA at 2 medical centers from 2006 to 2021, excluding patients with prior CAD, severe renal disease, and malignancy. Adjusted Cox regression was used to assess the association of CAD severity (absent, nonobstructive, obstructive) and extent (number of vessels with plaque) with adverse cardiovascular events (major adverse cardiovascular events [MACE]: cardiovascular death, nonfatal myocardial infarction, or ischemic stroke) across different age groups. RESULTS: Among 22,412 patients followed over a median of 6.2 years (Q1-Q3: 3.9-9.6 years), 16,726 were <65 years of age and 5,686 were ≥65 years of age. Older patients had a higher prevalence of obstructive CAD (38% vs 15%) and extensive plaque (52% vs 20% with 3- to 4-vessel involvement) compared with their younger counterparts. Nonobstructive plaque was common in both groups (<65 years of age: 37%; ≥65 years of age: 48%). Obstructive CAD was associated with MACE in both younger (HR: 2.45; P < 0.001) and older individuals (HR: 1.97; P < 0.001). Nonobstructive plaque was associated with MACE in younger individuals (HR: 1.39; P = 0.005), whereas only extensive nonobstructive CAD was associated with MACE in older individuals (HR: 1.56; P = 0.02). Among those with obstructive CAD on coronary CTA who underwent early invasive coronary angiography, revascularization was less common among older adults (48% vs 56%; P = 0.002). CONCLUSIONS: In a large coronary CTA registry, patients ≥65 years of age were more likely to have extensive plaque and stenosis. Although the prognostic value of coronary CTA may be lower among older adults with nonobstructive plaque (a group that has a similar event rate as those with no CAD), the presence of extensive nonobstructive plaque or obstructive stenosis was independently associated with a significantly higher rate of MACE. Newer techniques to better risk stratify patients with nonobstructive plaque may improve the value of coronary CTA, especially in older adults.