Bone Fragility Fractures in CKD Patients

Abstract

Chronic kidney diseases (CKD) are associated with mineral and bone diseases (MBD), including pain, bone loss, and fractures. Bone fragility related to CKD includes the risk factors observed in osteoporosis in addition to those related to CKD, resulting in a higher risk of mortality related to fractures. Unawareness of such complications led to a poor management of fractures and a lack of preventive approaches. The current guidelines of the Kidney Disease Improving Global Outcomes (KDIGO) recommend the assessment of bone mineral density if results will impact treatment decision. In addition to bone density, circulating biomarkers of mineral, serum bone turnover markers, and imaging techniques are currently available to evaluate the fracture risk. The purpose of this review is to provide an overview of the epidemiology and pathogenesis of CKD-associated bone loss. The contribution of the current tools and other techniques in development are discussed. We here propose a current view of how to better predict bone fragility and the therapeutic options in CKD.

Keywords: Bone; Bone mineral density; CKD-MBD; Calcium; Fracture; Imaging; Parathyroid hormone; Phosphate.

Fig. 1

Pathophysiology of fractures in CKD. Schematic representation of the changes induced by CKD: 25OHD 25hydroxy-vitamin D; 1,25(OH)2 D: 1–25 dihydroxy-vitamin D. PTH parathyroid hormone; Wnt wintless

Fig. 2

Guidelines for the management of fractures. A fragility fracture requires the measurement of bone mineral density and a deep analysis of mineral metabolism markers. The first step aims to rule out an osteomalacia with the use of bone biomarkers and if possible a bone biopsy. Guidelines are proposed as a function of PTH levels. Reduction of PTH should be achieved before the introduction of any anti-resorbing agents. BSAP bone-specific alkaline phosphatase