Comparison of markers for bone formation and resorption in premenopausal and postmenopausal subjects, and osteoporosis patients.

Abstract

Recently, the biochemical markers for bone metabolism have been developed and are expected to reflect the minor change of bone turnover. We compared bone formation markers: alkaline phosphatase-(Alp), bone gla-protein(BGP), carboxy-terminal propeptide of type I collagen(PICP); and bone resorption markers: carboxy-terminal telopeptide of type I collagen(ICTP), pyridinoline(Pyr), deoxypyridinoline(Dpyr) to see if they reflected the effects of aging and menopause in 95 premenopausal and 66 postmenopausal healthy subjects. We also compared the bone turnover in 29 vertebral osteoporosis patients. All markers except ICTP significantly increased with age in the healthy subjects. Alp, BGP, PICP, Pyr, and Dpyr were significantly higher in the postmenopausal group than in the premenopausal group. BGP, Pyr, and Dpyr in premenopausal subjects in their 50s were already significantly increased compared with BGP, Pyr, and Dpyr in premenopausal subjects in their 30s and 40s. To evaluate the discrimination power of the six markers in the postmenopausal subjects and in patients with osteoporosis, the z scores of six markers were calculated against the premenopausal group. z-scores of bone resorption markers(ICTP, Pyr, and Dpyr) were much higher than those of bone formation markers (Alp, BGP, and PICP) in patients with osteoporosis, even though z-scores of bone resorption markers were similar to those of bone formation markers in postmenopausal subjects. In conclusion, Alp, BGP, PICP, Pyr, and Dpyr had good performance in postmenopausal status. Resorption markers increased more than formation markers in osteoporosis subjects, and the bone turnover in osteoporosis subjects was more uncoupled than in postmenopausal subjects.