A Behre1, J Janott, M Pfohl, H Schatz, A Pfeiffer. 1. Abteilung für Endokrinologie und Stoffwechselerkrankungen, Medizinische Universitätsklinik Bergmannsheil Bochum. Ariane.Behre@t-online.de
Abstract
BACKGROUND: The diagnostic value of biochemical parameters of bone turnover for the diagnosis of osteoporosis is open to discussion. We investigated whether the determination of crosslinks, bone type I collagen degradation products, correctly identifies osteoporotic subjects. PATIENTS AND METHOD: In a sample of 370 individuals recruited at random within a population survey of vertebral osteoporosis, urinary concentration of total pyridinoline and desoxypyridinoline were determined by HPLC. Standardized lateral X-rays of the thoracic and lumbar spine were taken and evaluated morphometrically using the method described by Eastell-Melton. RESULTS: Crosslink excretion was significantly higher in female but not in male individuals with vertebral deformities as defined by Eastell. The specificity of these biochemical parameters with regard to radiological osteoporotic alterations was 76-81%, but the sensitivity was 32.4-42.9% only. CONCLUSION: Pyridinoline and desoxypyridinoline reflect the process of bone degradation which leads to vertebral deformity. Crosslinks are specific markers of bone resorption and provide a valid parameter in the diagnosis of osteoporosis. The low sensitivity indicates that the measurement of pyridinoline and desoxypyridinoline is less suitable for screening purposes, but may be useful in confirming presence or extent of osteoporosis.
BACKGROUND: The diagnostic value of biochemical parameters of bone turnover for the diagnosis of osteoporosis is open to discussion. We investigated whether the determination of crosslinks, bone type I collagen degradation products, correctly identifies osteoporotic subjects. PATIENTS AND METHOD: In a sample of 370 individuals recruited at random within a population survey of vertebral osteoporosis, urinary concentration of total pyridinoline and desoxypyridinoline were determined by HPLC. Standardized lateral X-rays of the thoracic and lumbar spine were taken and evaluated morphometrically using the method described by Eastell-Melton. RESULTS: Crosslink excretion was significantly higher in female but not in male individuals with vertebral deformities as defined by Eastell. The specificity of these biochemical parameters with regard to radiological osteoporotic alterations was 76-81%, but the sensitivity was 32.4-42.9% only. CONCLUSION:Pyridinoline and desoxypyridinoline reflect the process of bone degradation which leads to vertebral deformity. Crosslinks are specific markers of bone resorption and provide a valid parameter in the diagnosis of osteoporosis. The low sensitivity indicates that the measurement of pyridinoline and desoxypyridinoline is less suitable for screening purposes, but may be useful in confirming presence or extent of osteoporosis.