Vertebral fractures in dialysis : Endocrinological disruption of the bone-kidney axis

The occurrence of metabolic bone disease in patients with renal dysfunction is due to the key role played by the kidney in regulating calcium-phosphate metabolism. The incidence of hip fractures in end-stage renal disease is 3- to 4-fold higher than the general population, while poor data about vertebral fractures show similar prevalence. Bone health has been mainly evaluated in the general population through bone mass density (BMD) measurements, while in Chronic Kidney Disease (CKD) patients, bone turnover (low or high turnover) has been considered the most relevant parameter. Indeed, in CKD patients, the association between BMD and fractures is unclear, and even studies on established risk factors (body mass index, PTH, and vitamin D) for fractures have contrasting outcomes. Recently, an important association has been found between bone disorders and vascular calcifications in CKD patients that has changed the denomination of renal osteodystrophy in CKD mineral and bone disorder. In this article, a poorly investigated subject, vertebral fractures in CKD patients, is addressed, as it is underestimated despite its remarkable clinical relevance.