Serum markers of bone fragility in type-2 diabetes mellitus

Patients with type-2 diabetes mellitus (T2DM) have normal or increased bone mineral density (BMD) but despite that, they are characterized by an increased hip and vertebral fracture risk that involves the alteration of bone quality and not the reduction in bone mass. BMD is utilized for the diagnosis and evaluation of osteoporosis, but BMD itself cannot provide an accurate diagnosis of the individuals at increased risk of fracture and, therefore, studies have focused on identifying other risk factors that are partially or fully independent of BMD. The fracture risk score tool-FRAX® models provide information about a 10-year probability of osteoporotic fractures, but do not include risk factors specific to illness such as diabetes duration, diabetes drug therapy, glycemic control, or the presence of micro-vascular complications. Multiple markers have been investigated to provide information on the risk of fractures in patients with T2DM such as: advanced glycation end products (AGEs), insulin-like growth factor-I (IGF-I), osteocalcin (OC), adiponectin, and sclerostin, but epidemiological studies did not provide homogeneous information regarding the link between these markers and bone fragility in T2DM subjects. Markers that increase the accuracy of fracture risk estimation in patients with T2DM need to be identified and employed in current medical practice