Lower P1NP serum levels: a predictive marker of bone loss after 1 year follow-up in premenopausal systemic lupus erythematosus patients

• Published in: Osteoporosis international 2015-02, Vol.26 (2), p.459-467
• Main Authors: Seguro, L. P. C., Casella, C. B., Caparbo, V. F., Oliveira, R. M., Bonfa, A., Bonfa, E., Pereira, R. M. R.
• Format: Article
• Language: English
• Subjects: Absorptiometry, Photon; Adult; Biomarkers; Biomarkers - blood; Bone density; Bone Density - physiology; Bone Remodeling - physiology; Collagen Type I - blood; Endocrinology; Female; Follow-Up Studies; Hip - diagnostic imaging; Humans; Lumbar Vertebrae - diagnostic imaging; Lupus; Lupus Erythematosus, Systemic - blood; Medicine; Medicine & Public Health; Middle Aged; Original Article; Orthopedics; Osteoporosis; Osteoprotegerin - blood; Peptide Fragments - blood; Peptides - blood; Procollagen - blood; RANK Ligand - blood; Rheumatology; Risk factors; Womens health; Young Adult
• ISSN: 0937-941X; 1433-2965
• DOI: 10.1007/s00198-014-2860-9

Summary Predictors of bone mineral density (BMD) loss are additional tools in the management of osteoporosis in premenopausal women with systemic lupus erythematosus (SLE). This study provides original evidence that N-terminal propeptide of type 1 collagen (P1NP), the most specific bone formation marker, is a predictor of BMD loss in this group of women. Introduction SLE is associated with a high risk of low bone mass/fractures but this risk is still controversial in premenopausal women. Our aim was to determine the 1 year incidence of BMD loss in premenopausal SLE women and the value of bone turnover markers as predictors of this complication. Methods This study enrolled a convenience sample of 63 premenopausal SLE patients. BMD was evaluated by dual X-ray absorptiometry at lumbar spine and hip at baseline and after 12 months. BMD changes above the least significant change were considered significant. Serum levels of P1NP and CTX (electrochemiluminescence), OPG, and RANKL (ELISA) were determined at baseline. Results Mean age was 31.1 ± 6.8 years, and disease duration was 5.25 ± 3.8 years. 36.5 % of patients presented BMD loss and 17.5 % BMD gain at lumbar spine and/or hip. Patients were divided in three groups: BMD loss (BL), no BMD change (NC), and BMD gain (BG). Patients with BL and NC received similar cumulative/mean/maximum glucocorticoid doses during the study, but patients with BG received lower doses ( p