Use of bone turnover markers in clinical practice

Abstract

To describe the modalities and interest of the use of bone turnover markers (BTMs) in clinical practice for osteoporosis management. Serum procollagen type I N-terminal propeptide and serum collagen type I crosslinked C-telopeptide are respectively the formation and resorption markers recommended to use as references for bone remodelling assessment in clinical studies. Biochemical BTMs reflect changes in bone metabolism. In clinical practice, many factors influencing BTMs, variability needs to be integrated during all of the dosage process. They include sample collection and storage conditions, patient's characteristics and lifestyle habits, recent fracture. The reference intervals are also affected by the type of automated assays used to assess BTMs. Appropriate references measured with the same assay method must be used for the optimum interpretation of results. BTMs have been extensively used as indicators in the diagnosis and monitoring of osteoporosis. However, their interest was mainly demonstrated to reflect changes in bone metabolism under antiosteoporotic treatments in clinical studies. Significant reductions in BTMs associated with fracture risk reduction needs to be determined in the management of osteoporosis. The standardization of BTMs, assays with international reference standards should provide conditions to state on the applications of BTMs in routine clinical practice.