Carotid plaque components and other carotid artery features associated with risk of stroke: A systematic review and meta-analysis

To compare the difference in the risk of stroke for four kinds of carotid artery plaque and carotid artery stenosis.Literature was collected by searching the PubMed, Embase, Cochrane library and Ovid databases up to June 2022, using the free search terms "carotid plaque" and "stroke". Meta-analysis was performed on the selected articles using Stata16 to analyse the relationship of stroke risk factors.A total of 11 studies including 6661 participants were included. Meta-analysis results showed that the incidence of stroke was statistically significantly different between IPH (intraplaque haemorrhage) plaques and LRNC (lipid-rich necrotic core) plaques (RR: 1.27, 95% CI: 1.04-1.55, P < 0.05) and IPH plaques and calcification plaques (RR: 2.99, 95% CI: 1.74-5.14, P < 0.0001). Furthermore, there was a statistically significant difference between TRFC (thinned or ruptured fibrous caps) plaques and carotid artery stenosis (RR: 10.84, 95% CI: 5.60-20.98, P < 0.0001) and calcification plaques and carotid artery stenosis (RR: 0.83, 95% CI: 0.75-0.92, P < 0.0001). However, there was no statistically significant difference between the IPH and carotid artery stenosis (RR: 1.55, 95% CI: 0.68-3.52, P > 0.05), LRNC and TRFC (RR: 0.80, 95% CI: 0.11-5.82, P > 0.05), LRNC and calcification (RR: 1.81, 95% CI: 0.90-3.66, P > 0.05) and LRNC and carotid artery stenosis (RR: 1.40, 95% CI: 0.69-2.81, P > 0.05).IPH was associated with a higher incidence of stroke compared to LRNC and calcification plaques and TRFC has a higher risk of stroke than calcification plaques and carotid stenosis. This evidence suggests that IPH and TRFC may play an important role in predicting stroke.