Association between Apolipoproteins AI and B and Ultrasound Indicators of Carotid Atherosclerosis

Abstract

Background: Apolipoproteins A-I and B (apoA-I and apoB) may be better indicators of the risk of cardiovascular and cerebrovascular diseases than conventional risk factors (RFs). The onset of ischemic stroke (IS) may be preceded by the development of atherosclerotic changes in carotid arteries, which can be detected by ultrasound. Only a certain % of patients with IS have an (underlying) carotid etiology.

Objective: The aim of our study was to determine the association between ultrasound indicators of carotid atherosclerosis and the presence of apolipoproteins and other biomarkers in patients with IS.

Methods: The study included 120 patients with clinically first, non-cardioembolic ischemic stroke in the carotid circulation. For all patients the following data were recorded: risk factors (hypertension, diabetes, hyperlipoproteinemia, smoking, obesity, metabolic syndrome, (MetS) hyperhomocysteinemia and inflammation), and levels of blood pressure, glucose, glycosylated hemoglobin, lipids, apoA-I and apoB apolipoproteins, body mass index, homocysteine, and C-reactive protein (CRP). Carotid duplex ultrasound was used to measure carotid intima media thickness (cIMT) and determine the presence of an unstable (hypoechogenic) plaque.

Results: The most significant associations were found between cIMT and older age (β=0.230; p=0.006), lower concentrations of apoA-I (β=-0.244; p=0.008) and a higher apoB/apoA-I ratio (β=0.247; p=0.007). The presence of a hypoechogenic plaque was most significantly associated with increased concentrations of apoB (OR=2.29; 95% CI=4.9-173.5; p<0.0001), the presence of MetS (OR=9.2; 95% CI=2.9-29.2; p<0.0001) and elevated CRP (OR=2.7; 95% CI=1.1-6.9; p = 0.046).

Conclusion: Among RFs and their biomarkers, apoA-I, apoB and the apoB/apoA-I ratio showed strong association with ultrasound indicators of carotid atherosclerosis in IS patients.

Keywords: Apolipoproteins; apoA-I; apoB; carotid duplex ultrasound; carotid intima media thickness; hypoechogenic plaque; risk factors..