Oxidised low-density lipoprotein and arterial function in beta-thalassemia major.
OBJECTIVE
Vascular abnormalities such as endothelial dysfunction and arterial stiffness have been described in patients with beta-thalassemia major (beta-TM). Increased concentrations of oxidised low-density lipoprotein cholesterol (oxLDL) have been observed in those patients, but possible associations between oxLDL and arterial function in beta-TM have not been defined.


METHODS
Twenty-six patients (11 males) with beta-TM (age 23 +/- 4 yr) and 30 age and gender-matched healthy subjects were studied. Aortic stiffness was assessed by carotid-femoral pulse wave velocity (PWVc-f) using applanation tonometry; brachio-radial artery stiffness was assessed by carotid-radial PWV (PWVc-r). Flow-mediated dilatation (FMD) of the brachial artery and oxLDL (ELISA) were also measured.


RESULTS
Patients with beta-TM had higher oxLDL levels (68.6 +/- 13.7 mU/mg vs. 50.0 +/- 12.6 mU/mg, P = 0.005), decreased FMD (3.6 +/- 2.5% vs. 7.3 +/- 3.5%, P = 0.001) and higher PWVc-f compared with controls (8.4 +/- 1.7 vs. 7.2 +/- 1.1. P < 0.002). FMD of the brachial artery was negatively associated with OxLDL concentrations in simple linear (r(2) = -0.25, P = 0.001) and multiple linear regression analysis (beta = -0.242, P = 0.03, R(2) = 0.43, P = 0.0002). PWVc-r was positively associated with OxLDL (r(2) = 0.23, P = 0.003) and showed a tendency in multiple regression analysis (beta = 0.18, P = 0.05). PWVc-r and FMD were also significantly correlated (beta = -0.213, P = 0.04) in beta-TM patients. There was no association between oxLDL and PWVc-f.


CONCLUSIONS
An association between oxLDL, arterial elastic properties and endothelial dysfunction of muscular arteries was found. OxLDL may represent a contributing factor for the vascular manifestations described in beta-TM patients.
Stakos
Dimitrios A
DA
Cardiology Division, Democritus University of Thrace, Alexandroupolis, Greece. dstakos@med.duth.gr
Tavridou
Anna
A
Margaritis
Dimitrios
D
Tziakas
Dimitrios N
DN
Kotsianidis
Ioannis
I
Chalikias
George K
GK
Tsatalas
Kostantinos
K
Bourikas
George
G
Manolopoulos
Vangelis G
VG
Boudoulas
Harisios
H
D000328:Adult; D001158:Arteries / Q000503:physiopathology*; D001916:Brachial Artery / Q000503:physiopathology; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000503:physiopathology; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D011673:Pulsatile Flow; D014655:Vascular Resistance; D014664:Vasodilation; D055815:Young Adult; D017086:beta-Thalassemia / Q000503:physiopathology*
D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein