European Biological Variation Study (EuBIVAS): within- and between-subject biological variation estimates of ß-isomerized C-terminal telopeptide of type I collagen (ß-CTX), N-terminal propeptide of type I collagen (PINP), osteocalcin, intact fibroblast growth factor 23 and uncarboxylated-unphosphorylated matrix-Gla protein-a cooperation between the EFLM Working Group on Biological Variation and the International Osteoporosis Foundation-International Federation of Clinical Chemistry Committee on Bone Metabolism.

We have calculated the biological variation (BV) of different bone metabolism biomarkers on a large, well-described cohort of subjects. BV is important to calculate reference change value (or least significant change) which allows evaluating if the difference observed between two consecutive measurements in a patient is biologically significant or not. INTRODUCTION: Within-subject (CVI) and between-subject (CVG) biological variation (BV) estimates are essential in determining both analytical performance specifications (APS) and reference change values (RCV). Previously published estimates of BV for bone metabolism biomarkers are generally not compliant with the most up-to-date quality criteria for BV studies. We calculated the BV and RCV for different bone metabolism markers, namely ß-isomerized C-terminal telopeptide of type I collagen (ß-CTX), N-terminal propeptide of type I collagen (PINP), osteocalcin (OC), intact fibroblast growth factor 23 (iFGF-23), and uncarboxylated-unphosphorylated Matrix-Gla Protein (uCuP-MGP) using samples from the European Biological Variation Study (EuBIVAS). METHODS: In the EuBIVAS, 91 subjects were recruited from six European laboratories. Fasting blood samples were obtained weekly for ten consecutive weeks. The samples were run in duplicate on IDS iSYS or DiaSorin Liaison instruments. The results were subjected to outlier and variance homogeneity analysis before CV-ANOVA was used to obtain the BV estimates. RESULTS: We found no effect of gender upon the CVI estimates. The following CVI estimates with 95% confidence intervals (95% CI) were obtained: ß-CTX 15.1% (14.4-16.0%), PINP 8.8% (8.4-9.3%), OC 8.9% (8.5-9.4%), iFGF23 13.9% (13.2-14.7%), and uCuP-MGP 6.9% (6.1-7.3%). CONCLUSIONS: The EuBIVAS has provided updated BV estimates for bone markers, including iFGF23, which have not been previously published, facilitating the improved follow-up of patients being treated for metabolic bone disease.

Effects of alpidem in anxious elderly outpatients: a double-blind, placebo-controlled trial.

The efficacy and safety of alpidem, a new anxiolytic imidazopyridine, were compared with those of placebo in anxious elderly patients (65-80 years) by means of a randomized, double-blind, parallel group study. Following a 7-day "placebo run-in," 40 anxious patients were randomized to receive either alpidem or placebo. Daily doses ranging from 75 to 150 mg (25-50 mg t.i.d.) were administered for 3 weeks. Hamilton Rating Scale for Anxiety (HRSA), State Trait Anxiety Inventory (STAI-X1), Visual Analogue Scale (VAS), and Clinical Global Impression (CGI) were used on days 0, 3, 7, 14, and 21 for assessing efficacy. Psychomotor and mnesic performances were evaluated at the same time by means of the Digit Symbol Substitution Test (DSST), the Grünberger's test for fine motor coordination, and the Hawie's test for immediate memory. Possible adverse events were also recorded during the five visits. The anxiolytic efficacy of alpidem was significantly (p < 0.01) superior to that of placebo in all the rating scales adopted. The anxiolytic action was clearly evident from day 7. For most of the patients the active dose was 25 mg t.i.d. No relevant adverse effects were observed in both groups. No impairment of psychomotor and mnesic performances could be observed in the alpidem group. Alpidem is a new interesting anxiolytic drug for anxious elderly patients because it appears remarkably safe and, at effective doses, it does not impair psychomotor performances and cognitive functions.