Determinants of bone turnover markers in healthy premenopausal women.
Bone turnover markers (BTMs) are widely used for the management of osteoporosis, and the premenopausal reference range is the target value for the treatment of postmenopausal osteoporosis with antiresorbing agents. Three serum BTMs (serum C-telopeptide of type I collagen [CTX], osteocalcin [OC], and N-terminal propeptide of type I procollagen [P1NP]), serum calcium, creatinine, phosphate, magnesium, and follicle-stimulating hormone (FSH) were measured in 638 healthy premenopausal women aged 20-50 years. In 83 women on the contraceptive pill (CP), the levels of the three BTMs adjusted for all confounding factors were 14-26% lower (P < 0.005) than in non-CP users. In 18 women considered perimenopausal for serum FSH levels >30 IU/mL despite having regular menses, BTM levels were significantly higher than in age-matched women. This group of subjects and the women on the CP were excluded from further analysis. The three BTMs significantly decreased with advancing age and were negatively and independently correlated with body mass index (P < 0.001) and serum phosphate. In conclusion, we confirm that CP use is associated with significantly lower BTM values. An increase in BTM concentrations can be observed in perimenopausal women, i.e., women with normal menses but FSH levels >30 IU/mL. BTMs decrease substantially with advancing age, and this appears to be associated with changes in body weight and serum phosphate. New normative ranges for serum OC, CTX, and P1NP were identified; and our findings in general impose a redefinition of the criteria for establishing the normal ranges for BTMs.
Adami
Silvano
S
Rheumatology Unit, University of Verona, Ospedale di Valeggio, Valeggio, Verona, Italy. silvano.adami@univr.it
Bianchi
Gerolamo
G
Brandi
Maria Luisa
ML
Giannini
Sandro
S
Ortolani
Sergio
S
DiMunno
Ombretta
O
Frediani
Bruno
B
Rossini
Maurizio
M
D000328:Adult; D015415:Biomarkers / Q000097:blood*; D016723:Bone Remodeling / Q000502:physiology*; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D024042:Collagen Type I / Q000097:blood; D003404:Creatinine / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D008274:Magnesium / Q000097:blood; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides / Q000097:blood; D010710:Phosphates / Q000097:blood; D017697:Premenopause / Q000097:blood*; D011347:Procollagen / Q000097:blood; D012016:Reference Values
D015415:Biomarkers; D024042:Collagen Type I; D010446:Peptide Fragments; D010455:Peptides; D010710:Phosphates; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; C047202:procollagen Type I N-terminal peptide; D015675:Osteocalcin; D005640:Follicle Stimulating Hormone; D003404:Creatinine; D008274:Magnesium; D002118:Calcium