Effect of risedronate on speed of sound in postmenopausal women with osteoporosis

Aim: To examine the effects of treatment with risedronate for 1 year on speed of sound (SOS) of the calcaneus and bone turnover markers in postmenopausal women with osteoporosis. Methods: Thirty-eight postmenopausal women with osteoporosis who had been treated with risedronate for > 1 year were enrolled in the study. The SOS and bone turnover markers were monitored during treatment with risedronate for 1 year. Results: The urinary levels of cross-linked N-terminal telopeptides of type I collagen and serum levels of alkaline phosphatase were significantly decreased at 3 mo (-34.7%) and 12 mo (-21.2%), respectively, compared with the baseline values. The SOS increased modestly, but significantly by 0.65% at 12 mo compared with the baseline value. Treatment with risedronate elicited an increase in the SOS of the calcaneus exceeding the coefficient of variation in vivo (0.27%). Conclusion: The present study confirmed that risedronate suppressed bone turnover and elicited a clinically significant increase in the SOS of the calcaneus in postmenopausal women with osteoporosis.