Mineral Metabolism and Vascular Damage in Children on... : Journal of the American Society of Nephrology (original) (raw)

CLINICAL RESEARCH

Shroff, Rukshana C.*, †; Donald, Ann E.†; Hiorns, Melanie P.‡; Watson, Alan§; Feather, Sally‖; Milford, David¶; Ellins, Elizabeth A.†; Storry, Clare†; Ridout, Deborah**; Deanfield, John†; Rees, Lesley*

Departments of *Nephrourology, †Vascular Physiology, ‡Radiology, **Biostatistics, Great Ormond Street Hospital and Institute of Child Health, London, §Nottingham City Hospital, Nottingham, ‖St. James's University Hospital, Leeds, and ¶Birmingham Children's Hospital, Birmingham, United Kingdom

Correspondence: Dr. Rukshana Shroff, Research Registrar, Vascular Physiology Unit, Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK. Phone: 0207-4059200, ext. 0065; Fax: 0207-8138532; E-mail: [email protected]

Accepted July 2, 2007

Received December 23, 2006

Abstract

Cardiovascular disease is increasingly recognized as a life-limiting problem in young patients with chronic kidney disease, but there are few studies in children that describe its determinants. We studied the association of intact parathyroid hormone (iPTH) levels and their management on vascular structure and function in 85 children, ages 5–18 years, who had received dialysis for ≥6 months. Compared to controls, dialysis patients had increased carotid intima-media thickness and pulse-wave velocity. All vascular measures positively correlated with serum phosphorus levels, while carotid intima-media thickness and cardiac calcification score also correlated with iPTH levels. Patients with mean time-integrated iPTH levels less than twice the upper limit of normal (n = 41) had vascular measures that were comparable to age-matched controls, but those with iPTH levels greater than twice the upper limit of normal (n = 44) had greater carotid intima-media thickness, stiffer vessels, and increased cardiac calcification than controls. Patients with increased carotid intima-media thickness had stiffer vessels and a greater prevalence of cardiac calcification. There was a strong dose-dependent correlation between vitamin D and all vascular measures, and calcium intake from phosphate binders weakly correlated with carotid intima-media thickness. In conclusion, both iPTH level and dosage of vitamin D are associated with vascular damage and calcification in children on dialysis.