Carotid Plaques Show More Unstable Characteristics Between 2010 and 2021 After a Prior Decade of Stabilization

Previously we reported a time-dependent change in atherosclerotic carotid plaque characteristics, with decreasing destabilizing characteristics between 2002 and 2011. This observation was considered confirmative with a parallel improved adherence to medication and decrease in overall cardiovascular death in Western Europe. In the present study, we investigated whether these time-dependent changes in plaque characteristics still occurred over the past decade.

Using the Athero-Express biobank, atherosclerotic plaques of 1277 consecutive patients undergoing carotid endarterectomy included between 2010 and 2021 were analyzed to examine time-dependent changes in histological plaque characteristics in intervals of 2 years. These results were compared with our previous time-dependent plaque composition data between 2002 and 2011 consisting of 1660 patients.

In contrast with the period 2002 through 2011, the period 2010 through 2021 showed a significant increase in vulnerable plaque characteristics: large lipid cores, intraplaque hemorrhage, macrophages, and calcification. When adjusted for confounders related to these plaque characteristics, such as time to operation and preoperative type of symptoms, the adjusted odds ratios per 2-year increase in time were 1.204 (95% CI, 1.090-1.331; P<0.001) for calcification, 1.358 (95% CI, 1.230-1.502; P<0.001) for intraplaque hemorrhage, 1.271 (95% CI, 1.150-1.407; P<0.001) for plaques consisting of >40% fat, and 1.366 (95% CI, 1.238-1.511; P<0.001) macrophages. Use of statins increased in both the 2002 through 2011 and 2010 through 2021 periods.

Our study did not support a further increase in plaque-stabilizing features in carotid atherosclerotic plaques between 2010 and 2021. In contrast, plaques even showed features of destabilization in the present cohort.