摘要
Objective To evaluate the type I collagen cross linked N telopeptide (NTx) levels in human urine as an indicator of bone resorption rate in different ages, sex and in bone metabolic diseases.Methods Urinary NTx was determined by immunoassay in 591 Beijing healthy subjects aged from 0 to 86 years and 379 patients with bone metabolic diseases.Results The levels of urinary NTx were significantly higher in children than in adults (P<0.001) and higher in boys than in girls (P<0.01) and increased 1.4-2.2 times in postmenopausal females than in men and premenopausal women. Urine NTx had a positive linear correlation with urine HOP/Cr (r= 0.778, P< 0.01) and Ca/Cr ratio (r=0.320, P< 0.01 ), and a negative linear correlation with age (r= -0.523, P<0.01) and lumbar spine BMD (r= -0.426, P<0.01). The levels of urine NTx increased for 3.6 times in pregnancy, 1.5 times in osteoporosis, 1.9 times in fragility fracture, 3.6 times in chronic renal failure, 2.1 times in rickets and 7.2 times in multiple myeloma compared to age matched controls.Conclusions NTx in urine is a specific and sensitive indicator of bone resorption and is able to distingish normal premenopause from late osteoporotic patients. NTx could be used as diagnostic information about metabolic bone diseases, and to monitor antiresorptive therapy.
Objective To evaluate the type I collagen cross linked N telopeptide (NTx) levels in human urine as an indicator of bone resorption rate in different ages, sex and in bone metabolic diseases.Methods Urinary NTx was determined by immunoassay in 591 Beijing healthy subjects aged from 0 to 86 years and 379 patients with bone metabolic diseases.Results The levels of urinary NTx were significantly higher in children than in adults (P<0.001) and higher in boys than in girls (P<0.01) and increased 1.4-2.2 times in postmenopausal females than in men and premenopausal women. Urine NTx had a positive linear correlation with urine HOP/Cr (r= 0.778, P< 0.01) and Ca/Cr ratio (r=0.320, P< 0.01 ), and a negative linear correlation with age (r= -0.523, P<0.01) and lumbar spine BMD (r= -0.426, P<0.01). The levels of urine NTx increased for 3.6 times in pregnancy, 1.5 times in osteoporosis, 1.9 times in fragility fracture, 3.6 times in chronic renal failure, 2.1 times in rickets and 7.2 times in multiple myeloma compared to age matched controls.Conclusions NTx in urine is a specific and sensitive indicator of bone resorption and is able to distingish normal premenopause from late osteoporotic patients. NTx could be used as diagnostic information about metabolic bone diseases, and to monitor antiresorptive therapy.
