Arterial distensibility in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease that is atherogenic. Decreased arterial distensibility (AD) is a risk factor for cardiovascular disease, and this precursor may be associated with SLE. Accordingly, we tested the hypothesis that patients with SLE will have significantly (p < 0.05) decreased AD when compared to normal, healthy age, and gender matched controls. Noninvasive, high resolution ultrasound was performed on 30 patients with chronic SLE and 16 age and gender matched controls. All were female. Maximum systolic and minimum diastolic diameters (mm) and intima-media thickness (IMT, mm) in the right common carotid artery were measured from M-mode images. In vitro arterial models were used for quality control. With a single, blinded observer, the 95% confidence levels for accuracy and precision for noninvasive systolic and diastolic tonometric arm blood pressures (SBP, DBP) and carotid sonographic diameters were approximately 5 mmHg and approximately 0.10 mm, respectively. Derived measurements for strain (%), stiffness (units), and AD (units) were determined by published arterial mechanical models and algorithms. Results (mean/standard deviation) were as follows: (patients/controls; # =p<0.05) Age 39/11, 35/11 years; SBP 130/20, 117/8# mmHg; DBP 82/11, 74/9# mmHg; strain 11/4, 11/4 %); stiffness 19/10, 17/11 units; IMT 0.44/0.08, 0.41/0.06 mm; AD 3.10/1.49, 3.30/1.63 units. There were no statistically significant differences (p<0.05) in measurements of AD and IMT in the common carotid artery between relatively young SLE patients and well matched controls.