Bone Microarchitecture in Hemodialysis Patients Assessed by HR-pQCT

Abstract

SummaryBackground and objectives Dialysis patients are at high risk for low-trauma bone fracture. Bone density measurements using dual-energy x-ray absorptiometry (DXA) do not reliably differentiate between patients with and without fractures. The aim of this study was to identify differences in bone microarchitecture between patients with and without a history of fracture using high-resolution peripheral quantitative computed tomography (HR-pQCT).Design, setting, participants, & measurements Seventy-four prevalent hemodialysis patients were recruited for measurements of areal bone mineral density (aBMD) by DXA and bone microarchitecture by HR-pQCT. Patients with a history of trauma-related fracture were excluded. Forty healthy volunteers served as controls. Blood levels of parathyroid hormone, vitamin D, and markers of bone turnover were determined.Results Dialysis patients, particularly women, had markedly impaired bone microarchitecture. Patients with fractures had significantly reduced cortical and trabecular microarchitecture compared with patients without fractures. aBMD tended to be lower in patients with fractures, but differences were statistically not significant. The strongest determinant of fracture was the HR-pQCT-measured trabecular density of the tibia, which also had the highest discriminatory power to differentiate patients according to fracture status. Radial DXA had a lower discriminatory power than trabecular density. ConclusionsBone microarchitecture is severely impaired in dialysis patients and even more so in patients with a history of fracture. HR-pQCT can identify dialysis patients with a history of low-trauma fracture.

Alterations of bone microstructure and strength in end-stage renal failure

“…By integrating all microstructural variables, FEA-determined bone strength might be a more valid outcome to study the consequences of ESRD on bone than isolated variables. These results are similar to two recent publications [14,15] and do not support the hypothesis of a selective cortical bone deficit in dialysis patients.…”

“…These findings are in .05 as compared with gender-matched young healthy controls; ** p<0.01 as compared with gender-matched young healthy controls; *** p<0.05 as compared with age-, weight-, height-, and gender-matched controls; **** p<0.01 as compared with age-, weight-, and gender-matched controls NA not assessed a For the "% Difference" variable, given the skewness and large range of the percent difference of cortical porosity, the median was computed agreement with our results insofar as we observed also alterations in both cortical and trabecular compartments. The capacity of HR-pQCT to discriminate between patients with and without fractures in comparison to DXA in ESRD patients was also recently reported [15]. Whilst all these studies were cross-sectional, they often do not specify whether the fractures occurred during the dialysis period or previously.…”

“…CT datasets from individual scans can be used for microstructural finite-element analysis (FEA) to assess bone mechanical competence (failure load and stiffness). Few studies have evaluated hemodialysis patients with these techniques [14,15], but they indicate an alteration of both cortical and trabecular bone compartments in relation to the severity of secondary hyperparathyroidism. The aim of this study was to analyze bone 3D microstructure, CtPo, and biomechanical properties in both compression (FEA) and torsion (polar moment of inertia) by HR-pQCT in ESRD patients compared to age-, gender-, and weightmatched healthy controls.…”

A Trimodality Comparison of Volumetric Bone Imaging Technologies. Part III: SD, SEE, LSC Association With Fragility Fractures

“…A number of studies have examined the association between volumetric bone apparent microstructural outcomes and fractures using HR-pQCT at the radius (2,9-16) and tibia (10,(13)(14)(15)(16). However, only few have investigated the same using either pQCT (3,(17)(18)(19) or MRI (1,(20)(21)(22)(23).…”

Osteoporosis in mineral and bone disorders of chronic kidney disease

“…17,19 FRAX, World Health Organization Fracture Risk Assessment tool, which incorporates anthropometric and demographic data, previous fractures, exposure to steroids, history of rheumatoid disease, and other causes of secondary osteoporosis as well as BMD of the femoral neck, has not been validated as a predictor of fractures in patients with moderate-to-advanced CKD. 20 The more mineral disappears from the bone, the more mineral goes to the vessels The relationship between increased risk of cardiovascular complications, death, decreased BMD, and fractures has been described in the general population, especially among postmenopausal women.…”