A new longitudinal study of adults with subclinical carotid atherosclerosis found that plaques with calcification were significantly more likely to evolve into lesions with intraplaque hemorrhage—a marker associated with increased stroke risk.

Using serial magnetic resonance imaging (MRI) over 6 years, researchers tracked 802 participants who were aged 45 years and older and observed patterns of plaque progression based on preexisting composition, age, and sex.

Participants were enrolled from a population-based study in the Netherlands. All had carotid intima-media thickness greater than 2.5 mm but were asymptomatic. Baseline MRI scans were conducted between 2007 and 2012, with follow-up scans between 2014 and 2017.

At baseline, 66.6% of plaques showed calcification, 31.6% had lipid-rich necrotic cores (LRNC), and 18.1% had intraplaque hemorrhage (IPH). Only 2.9% of plaques showed more than 50% stenosis, which indicated early-stage disease in most participants.

At follow-up, 19% of plaques had developed new IPH. After adjusting for plaque thickness, luminal stenosis, cardiovascular risk factors, and medication use, the analysis showed that baseline calcification was associated with a twofold increased risk of developing IPH (adjusted odds ratio [OR] = 2.00, 95% confidence interval [CI] = 1.26–3.16, P = .003). When both calcification and LRNC were present, the risk was even higher (adjusted OR = 3.07, 95% CI = 1.78–5.30, P < .001).

Simulations of 30-year plaque progression indicated that most plaques with no or only one component eventually developed into multicomponent plaques. The proportion of multicomponent plaques increased from 10% at age 55 to more than 50% after age 70.

The study also identified sex-based differences in plaque evolution. Men were more likely than women to have plaques progress to multicomponent lesions with IPH (21% vs 13%, P < .001). At baseline, multicomponent plaques were more common in men (35%) than in women (22%).

Additional image analyses confirmed that calcification frequently preceded IPH. Among participants with three serial MRI scans, 93% of plaques that developed IPH had calcification detected earlier.

Baseline IPH was also associated with incident calcification (adjusted OR = 3.10, 95% CI = 1.06–9.09, P = .04), though this relationship was not significant when more data were included. No significant associations were found between baseline components and new LRNC.

The study suggests that plaque composition, particularly the presence of calcification, may influence future vulnerability, even in the absence of significant stenosis.  

The authors note that additional research is needed to investigate the morphology of calcification and its potential role in the development of intraplaque hemorrhage.

Full disclosures can be found in the study.

Source: RSNA