Bone Mineral Density and Vascular Calcification in Children and Young Adults With CKD 4 to 5 or on Dialysis

Alexander D Lalayiannis; Nicola J Crabtree; Charles J Ferro; David C Wheeler; Neill D Duncan; Colette Smith; Joyce Popoola; Askiti Varvara; Andromachi Mitsioni; Amrit Kaur; Manish D Sinha; Lorenzo Biassoni; Simon P McGuirk; Kristian H Mortensen; David V Milford; Jin Long; Mary D Leonard; Mary Fewtrell; Rukshana Shroff

doi:10.1016/j.ekir.2022.10.023

Bone Mineral Density and Vascular Calcification in Children and Young Adults With CKD 4 to 5 or on Dialysis

Kidney Int Rep. 2022 Nov 2;8(2):265-273. doi: 10.1016/j.ekir.2022.10.023. eCollection 2023 Feb.

Authors

Alexander D Lalayiannis^{1

2}, Nicola J Crabtree³, Charles J Ferro⁴, David C Wheeler⁵, Neill D Duncan⁶, Colette Smith⁷, Joyce Popoola⁸, Askiti Varvara⁹, Andromachi Mitsioni⁹, Amrit Kaur¹⁰, Manish D Sinha¹¹, Lorenzo Biassoni¹², Simon P McGuirk¹³, Kristian H Mortensen¹⁴, David V Milford², Jin Long¹⁵, Mary D Leonard¹⁶, Mary Fewtrell¹⁷, Rukshana Shroff^{12

18}

Affiliations

¹ Pediatric Nephrology, Birmingham Women's and Children's Hospitals, National Health Service Foundation Trust, Birmingham, UK; University College London Great Ormond Street Hospital Institute of Child Health, London, UK.
² Nephrology, Birmingham Children's Hospital, Birmingham, UK.
³ Densitometry Department, Birmingham Women's and Children's Hospitals National Health Service, Foundation Trust, Birmingham, UK.
⁴ Renal Unit, University Hospitals Birmingham, Birmingham, UK.
⁵ Department of Renal Medicine, University College London, London, UK.
⁶ Imperial College Healthcare National Health Service Trust, Renal and Transplant Center, London, UK.
⁷ Institute of Global Helath, University College London, London, UK.
⁸ St. George's University Hospital National Health Service Foundation Trust, London, UK.
⁹ Department of Pediatric Nephrology, "P & A Kyriakou" Children's Hospital, Athens, Greece.
¹⁰ Pediatric Nephrology, Manchester University National Health Service Foundation Trust, Manchester, UK.
¹¹ Pediatric Nephrology, Evelina Children's Hospital, London, UK.
¹² University College London Great Ormond Street Hospital Institute of Child Health, London, UK.
¹³ Radiology Department, Birmingham Women's and Children's Hospitals National Health Service Foundation Trust, Birmingham, UK.
¹⁴ Department of Cardiac Imaging, University College London Great Ormond Street Hospital Institute of Child Health, London, UK.
¹⁵ Stanford University School of Medicine, Palo Alto, California, USA.
¹⁶ Pediatrics, Stanford University School of Medicine, Palo Alto, California, USA.
¹⁷ University College London Great Ormond Street Institute of Child Health, Population Policy and Practice, Childhood Nutrition Research Center, London, UK.
¹⁸ Great Ormond Street Hospital, London, UK.

Abstract

Introduction: Older adults with chronic kidney disease (CKD) can have low bone mineral density (BMD) with concurrent vascular calcification. Mineral accrual by the growing skeleton may protect young people with CKD from extraosseous calcification. Our hypothesis was that children and young adults with increasing BMD do not develop vascular calcification.

Methods: This was a multicenter longitudinal study in children and young people (5-30 years) with CKD stages 4 to 5 or on dialysis. BMD was assessed by tibial peripheral quantitative computed tomography (pQCT) and lumbar spine dual-energy X-ray absorptiometry (DXA). The following cardiovascular imaging tests were undertaken: cardiac computed tomography for coronary artery calcification (CAC), ultrasound for carotid intima media thickness z-score (cIMTz), pulse wave velocity z-score (PWVz), and carotid distensibility for arterial stiffness. All measures are presented as age-adjusted and sex-adjusted z-scores.

Results: One hundred participants (median age 13.82 years) were assessed at baseline and 57 followed up after a median of 1.45 years. Trabecular BMD z-score (TrabBMDz) decreased (P = 0.01), and there was a nonsignificant decrease in cortical BMD z-score (CortBMDz) (P = 0.09). Median cIMTz and PWVz showed nonsignificant increase (P = 0.23 and P = 0.19, respectively). The annualized increase in TrabBMDz (ΔTrabBMDz) was an independent predictor of cIMTz increase (R ² = 0.48, β = 0.40, P = 0.03). Young people who demonstrated statural growth (n = 33) had lower ΔTrabBMDz and also attenuated vascular changes compared with those with static growth (n = 24).

Conclusion: This hypothesis-generating study suggests that children and young adults with CKD or on dialysis may develop vascular calcification even as their BMD increases. A presumed buffering capacity of the growing skeleton may offer some protection against extraosseous calcification.

Keywords: carotid intima media thickness; chronic kidney disease; coronary artery calcification; dialysis; dual-energy X-ray absorptiometry; peripheral quantitative CT scan.