Biochemical markers of bone turnover

Recent developments in biomarkers in many fields of medicine have expanded the array of tools health care providers can use today for disease management. Essentially, biomarkers assist clinicians today in four main ways: screening, diagnosis, assessment of severity or risk, and monitoring of, or deciding on, treatment (1). Surrogate markers known as biochemical markers of bone turnover have been used for decades in the management of diseases of the skeleton. Historically, bone biomarkers required 24-h urine collections, lacked accuracy and reliability, and were cumbersome to use. More recently, they have been shown to be effective surrogates for assessments of treatment response and efficacy in osteoporosis. Although used extensively in research and development and in metabolic bone disease clinics, they are still infrequently used tools for osteoporosis management in clinical practice. Today they have been incorporated into the assessment and management of a variety of diseases of bone including complex metabolic bone disorders, osteoporosis, Paget's disease of bone, and skeletal metastases. Developments in the last decade have greatly enhanced their performance characteristics. A variety of tests and assays are now widely available and significantly more accurate and reliable measures of bone metabolism have been developed. However, techniques and assays vary substantially. In order to maximize their clinical usefulness, an understanding of their strengths and weaknesses, factors that influence them, and knowledge of their unique intricacies is crucial for the ordering physician during the decision- making process. As the field continues to develop, more specific markers and standardization of measurement techniques will enhance reliability, which facilitate their use in practice. The aim of this review is to increase knowledge of the variety of tests available, their potential and limitations, and current best practice for practitioners and researchers, focusing primarily on their use in the management of osteoporosis. © Copyright 2006 by Humana Press Inc. All rights of any nature whatsoever reserved.