Vascular function in children after renal transplantation.
BACKGROUND
Atherosclerotic complications are the main cause of death in adult patients with renal failure. Endothelial dysfunction is a hallmark of early atherosclerotic changes. The numerous risk factors for endothelial dysfunction present in adults are present in children with renal failure, as well. In addition to this, increased stiffness of the arterial tree conveys an increased risk for cardiovascular mortality. The aim of this study is to investigate whether pediatric kidney recipients already show endothelial dysfunction and have increased arterial stiffness.


METHODS
We investigated 20 pediatric kidney recipients with stable graft function and 20 healthy children. Endothelial function was studied noninvasively with ultrasound and digital signal analysis equipment as the percentage of post-ischemic flow-mediated dilatation (FMD) of the brachial artery. Parameters of arterial distensibility were calculated from distension of the brachial artery during the cardiac cycle, pulse pressure, and baseline diameter.


RESULTS
FMD was significantly less in patients (7.7% +/- 5.4%) than controls (15.0% +/- 7.1%; P < 0.001), indicating endothelial dysfunction in pediatric kidney recipients. Impairment of FMD was found predominantly in patients being treated for hypertension. Arterial distensibility was diminished in patients (3.4 +/- 2.8 versus 5.7 +/- 3.3 10(-3)/mm Hg; P < 0.02), indicating increased stiffness of the arterial tree. Patients had a greater baseline diameter of the brachial artery adjusted for height than healthy controls at equal blood pressure.


CONCLUSIONS
These findings suggest arterial wall changes in pediatric renal transplant recipients. They are already at risk for premature development of atherosclerotic complications and cardiovascular mortality.
Lilien
Marc R
MR
Department of Paediatric Nephrology, Wilhelmina Children's Hospital, Amsterdam, The Netherlands. m.lilien@wkz.azu.nl
Stroes
Erik S
ES
Op't Roodt
Jos
J
de Jongh
Saskia
S
Schröder
Cornelis H
CH
Koomans
Hein A
HA
D000293:Adolescent; D000328:Adult; D001161:Arteriosclerosis / Q000000981:diagnostic imaging / Q000453:epidemiology; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000401:mortality; D002648:Child; D004108:Dilatation, Pathologic / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000453:epidemiology; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy; D016030:Kidney Transplantation / Q000502:physiology*; D008297:Male; D012039:Regional Blood Flow / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods; D014664:Vasodilation / Q000502:physiology