Urinary excretion of type I collagen degradation products in healthy women and osteoporotic patients with vertebral and hip fractures

We have evaluated both the effect of normal aging and menopause on urinary CrossLaps(TM) (u-CTx) excretion and the bone resorption status by u-CTx in patients with vertebral fracture and hip fracture. In 246 healthy women, 76 patients with vertebral fracture, and 63 patients with hip fracture, LI-CTX excretion was measured by ELISA. The age-related changes of u-CTx in healthy females reflected the marked increase of bone resorption associated with modeling at childhood. The values in the subgroups of postmenopausal women 1-3 years since menopause and less than or equal to 10 years since menopause were significantly higher than those in the subgroups of premenopausal adult women. The values In the vertebral fracture group were significantly higher than those in the premenopause group, but not those in the postmenopause groups. The values in the hip fracture group were significantly higher than those in the other groups, Of the 70 postmenopausal subjects aged 45-64 years, 43% had u-CTx values more than 2 SD above premenopausal mean. The corresponding values in the patients with vertebral fracture and those with hip fracture were 58% and 64%, respectively. This marker reflects well the increase of bone resorption associated with bone modeling al childhood and with high bone turnover after menopause. The excretions in the patients with hip fracture were much higher than those in the age-matched subjects and also higher than those in the patients with vertebral fracture. These findings indicate that the abnormality of bone resorption in the patients with hip fracture is more severe than in the patients with vertebral fracture.