Assessment of different markers of bone resorption in postmenopausal osteoporotic women treated with pamidronate

The aim of this study was to evaluate the different bone resorption markers, total pyridinoline (Pyr) and total deoxypyridinoline (Dpyr), assessed by a HPLC method, free Dpyr, assessed by a new immunoassay, and urinary excretion of hydroxyproline (OH-proline), in postmenopausal osteoporotic women during long-term treatment with pamidronate.A total of 60 postmenopausal women with previous distal forearm fracture were included in this 12-month placebo-controlled and double-blind study, where intermittent oral pamidronate, 75 or 150 mg, or placebo were given daily for 4 weeks, every 16 weeks. After 1 week a significant reduction in urinary excretion of total Dpyr was observed in the group treated with 150 mg pamidronate compared to the placebo (p<0.01) and to the 75-mg group (p<0.001). A maximal 50.4% decrease in total Dpyr, (p<0.0001 compared to the placebo group, p<<0.01 compared to the 75-mg group), was observed after 3 weeks of treatment with 150 mg pamidronate, and this decrease persisted to week 52. Af...