CD4⁺CD28⁻ lymphocytes and ischaemic stroke. Part I: CD4⁺CD28⁻ lymphocytes and common carotid artery intima-media thickness

Using ultrasound radio frequency technology to assess regression of the structure and function of the carotid artery by radioiodine therapy in hyperthyroidism patients

INTRODUCTION

The aim of the study was to investigate the structure and function of the carotid artery in patients with hyperthyroidism by ultrasound radio frequency data technology (RF data) and the effect of (131)I on them.

MATERIAL AND METHODS

Seventy patients with primary hyperthyroidism and 74 healthy volunteers were enrolled in this study. Structural and functional parameters of the common carotid artery were measured in every patient before and after (131)I treatment through the RF data, such as intima media thickness (IMT), functional compliance coefficient (CC), stiffness index (β), and pulse wave velocity (PWV). We also analyzed the correlation between these parameters and patients' age, body mass index, hemodynamic parameters (blood pressure, heart rate), thyroid hormone levels and other risk factors.

RESULTS

There was a significant difference in IMT between hyperthyroid patients and the control group at baseline (483.6 vs. 443.3 µm, p < 0.01); after treatment, the IMT decreased significantly (428.7 vs. 483.6 µm, p < 0.001). Furthermore, the IMT was correlated with patients' age and systolic blood pressure (r = 0.525, p < 0.01 and r = 0.289, p < 0.05, respectively). The β and PWV were also higher than the control group (7.26 vs.5.87, 6.27 vs. 5.57 m/s, respectively; all p < 0.001); CC was lower than the control group (0.98 vs. 1.19 mm(2)/KPa, p < 0.01); after treatment, PWV and β were lower than baseline (5.66 vs. 6.27, 5.81 vs. 7.26 m/s, respectively; all p < 0.01), and CC was higher than baseline. In addition, they were significantly correlated with age (r = 0.525, p < 0.01 and r = 0.289, p < 0.05, respectively). However, these parameters were not correlated with the level of thyroid hormones.

CONCLUSIONS

Six-month (131)I treatment for patients with hyperthyroidism reverses the structural and functional damage in the carotid artery, which is sensitively evaluated by the RF data technique.

CD4⁺CD28⁻ lymphocytes and cerebral ischaemic stroke. Part II: CD4⁺CD28⁻ lymphocytes and carotid artery atherosclerotic plaque characteristics

BACKGROUND AND PURPOSE

CD4⁺CD28⁻ lymphocytes can directly contribute to the instability of atherosclerotic plaque. This paper attempts to answer the question of the potential influence of the CD4⁺CD28⁻ lymphocyte population on the ultrasound image of atherosclerotic plaque in the common carotid artery (CCA) wall.

MATERIAL AND METHODS

The study involved a group of 109 patients, aged 45 to 65 years, including 42 patients with first ever ischaemic stroke, experiencing symptoms resulting from disturbances of the anterior area of cerebral circulation, arterial hypertension and/or type 2 diabetes mellitus (group 1). Group 2 consisted of 34 patients with mentioned risk factors, without ischaemic stroke. The control group comprised 33 heal-thy individuals. The percentage of CD4⁺CD28⁻ lymphocytes was assessed with flow cytometry.

RESULTS

A significant difference in the incidence of heterogeneous plaques was noted between groups 1 and 3 (p = 0.0023) as well as between group 2 and 3 (p = 0.0005), whereas groups 1 and 2 did not differ from each other. The proportion of CD4⁺CD28⁻ lymphocytes was similar in groups 1 and 2 (p = 0.97), but it differed between groups 1 and 3 (p < 0.0001) and between groups 2 and 3 (p < 0.001). A correlation was found between the proportion of CD4⁺CD28⁻ lymphocytes in the blood and the number of CCA atherosclerotic plaques (Rs = 0.191, p = 0.046). The proportion of CD4⁺CD28⁻ lymphocytes in peripheral blood did not correlate with the ultrasound types of atherosclerotic plaques. No correlation between the proportion of CD4⁺CD28 ⁻lymphocytes and the area of atherosclerotic plaques was found.

CONCLUSIONS

The correlation between the proportion of CD4⁺CD28⁻ lymphocytes and the number of atherosclerotic plaques within the CCA suggests that the cells are involved in the mechanism of carotid plaque formation. There is no proof of the involvement of the above-mentioned cells in the mechanism of plaque destabilization in those arteries.