of C-telopeptide cross-links (sCTX), a marker of bone resorption, was measured using an enzyme- linked immunosorbent assay (Serum CrossLaps®ELISA–Nordic Bioscience Diagnostic, formerly Osteometer BioTech, Herlev, Denmark). All the assays were performed in duplicate per batch of maximum 140 and 86 unknown serum samples for b-ALP and sCTX, respectively. If the CV on the duplicate measurement was higher than 15%, the sample was re-assayed in a run control. In each assay run, two quality RG7112 price control samples (QCs) were assayed before and after the unknown samples. The assay run was validated if the CV on the duplicate measurement of a QC was lower or equal to 15%, if the QCs results were in their respective 2SD ranges determined previously and if the difference between the results obtained before and after the unknown samples Y-27632 nmr did not exceed 15%. Both
clinical studies were conducted in accordance with the ethical principles stated in the Declaration of Helsinki, 1964, as revised in Hong Kong, 1989. The study protocol was approved by independent ethics committees in each country and/or centre. All patients gave written informed consent. Statistical analysis All analyses were performed in accordance with the intention-to-treat principle: The population included all patients having a baseline and post-baseline lumbar X-ray and having a baseline value for b-ALP or sCTX. Groups were compared at baseline on the lumbar and femoral BMD Epigenetics inhibitor and corresponding T-scores using an ANOVA analysis, adjusted or not on age. Vertebral fracture risk was assessed as the number of patients with at least one new osteoporotic vertebral fracture, analysed by the Kaplan–Meier method. Patients were stratified into tertiles of baseline (pre-treatment) levels of b-ALP and sCTX.
PtdIns(3,4)P2 The boundaries of the tertiles and the normal ranges for b-ALP and sCTX are given in Table 1. Between-treatment differences in vertebral fracture risk over 3 years for each tertile were assessed using an unadjusted Cox model. Sensitivity analysis was performed using a Cox model adjusted for baseline lumbar BMD. Table 1 Tertile boundaries and normal ranges for markers of bone turnover (b-ALP and sCTX) Tertile 1 Tertile 2 Tertile 3 b-ALP (µg/L)a ≤10.0 >10.0–≤13.3 >13.3 sCTX (ng/mL)b ≤0.423 >0.423–≤0.626 >0.626 ab-ALP, bone-specific alkaline phosphatase: normal range, 2.9–14.5 µg/L (premenopausal women); 3.8–22.6 µg/L (post-menopausal women) bsCTX, serum C-telopeptide cross-links: normal range, 0.112–0.323 ng/mL (pre-menopausal women); 0.153–0.625 ng/mL (post-menopausal women) Further between-treatment comparisons, using the same model, were performed for those patients who were in the lowest tertile for both b-ALP and sCTX (representing patients with the lowest bone turnover) and for patients in the highest tertile for both b-ALP and sCTX (representing those with the highest bone turnover).