Laboratory-based Biomarkers for Risk Prediction, Auxiliary Diagnosis and Post-operative Follow-up of Osteoporotic Fractures

Osteoporosis (OP) is characterized by degraded bone microstructure, loss of bone mass and increased risk of fragility fractures. Currently, T-score determined by dual-energy X-ray absorptiometry (DEXA) measurements has been regarded as the gold standard for the diagnosis of osteoporosis. However, multiple factors have indicated that the T-score is insufficient to identify individuals with osteoporosis at a potentially high risk of fracture, or accurately detect those who require treatment, or continuously monitor the risk of re-fracture and clinical outcomes after treatment. This review covers publications in a range of ten years and comprehensively summarizes the studies in laboratory-based biomarkers for osteoporotic fractures (OF), aiming to provide physicians and surgeons with an update of clinical research in identification, verification and application of these tools, and to provide useful information for the design of future clinical studies.

It was found that bone formation markers (such as PINP, BGP, ECM1 and SOST), bone resorption markers (such as β-CTX, TRAcP5b, osteocalcin, RANKL, RANKL/OPG ratio, and t-PINP/β-CTX), hormonal biomarkers (such as IGF- 1, PTH, leptin, adiponectin and AMH), indicators of inflammation and oxidative stress (SII, IL- 6, LTL, FlOP_360, FlOP_400, and GGT), microRNAs (such as miR- 21, miR- 320a- 3p, miR- 491 - 5p, miR- 485 - 3p, miR- 19b- 1- 5p, miR- 203a, miR- 31 - 5p, miR- 502 - 3p, miR- 4739, miR- 497, miR- 19b, and miR- 107), other biomarkers (SAF-AGEs and glycine), adipocytokines (irisin and Omentin- 1), senescence biomarkers (RDW), and lncRNAs (MIAT) may be useful biomarkers for clinical practice.

Further validation of these biomarkers and a better understanding of the underlying molecular mechanisms may help in the development and application of these biomarkers for risk prediction of OF, differential diagnosis among OP, OF and healthy individuals, as well as post-operative monitoring of re-fracture risk and treatment outcomes.