Carotid plaque characteristics and their association with cardiovascular risk factors and coronary atherosclerosis in a middle-aged population.

BACKGROUND

Carotid and coronary atherosclerosis are critical determinants of cardiovascular risk, yet their interrelationship in middle-aged populations is incompletely understood. This study assessed carotid plaque composition, risk-factor associations, coronary disease, and sex differences in a subclinical cohort.

METHODS

Within the Swedish CArdioPulmonary bioImage Study, 533 asymptomatic individuals aged 50-64 years with carotid plaque ≥2.7 mm on ultrasound underwent 3T multi-contrast carotid cardiovascular magnetic resonance (CMR) and coronary computed tomography angiography. Carotid plaque characteristics were determined manually using established criteria on multi-contrast weighted carotid CMR. Bayesian regression models evaluated associations between cardiovascular risk factors and coronary atherosclerosis.

RESULTS

Lipid-rich necrotic core (LRNC) was present in 60% (320/533) and intraplaque hemorrhage (IPH) in 5.4% (29/533); calcification occurred in 48.6% (259/533). Maximum carotid wall thickness was 1.8 (1.6-2.0) mm, and mean lumen area 31.3 (26.7-36.1) mm². Coronary atherosclerosis was present in 63.6% (339/533) of participants, with ≥50% stenosis in 12.9% (69/533), and coronary artery calcium score >400 in 12.8% (68/533). Men (N = 367) had larger carotid lumen area, mean wall area, and maximum wall thickness (all p < 0.001) than women (N = 166), differences that persisted after body-surface-area adjustment (all p < 0.01). LRNC was present in 66% (242/367) of men compared to 47% (78/166) of women (p < 0.001). LRNC presence was not associated with coronary atherosclerosis, whereas IPH was associated with coronary involvement.

CONCLUSION

In middle-aged individuals, distinct cardiovascular risk factors were positively linked to the presence and volume of LRNC and calcified plaques. The substantial prevalence of high-risk plaque features, particularly LRNC and especially in men, highlights a significant subclinical carotid disease burden.