@article{3159487,
    title = "Early changes in biochemical markers of bone formation during
teriparatide therapy correlate with improvements in vertebral strength
in men with glucocorticoid-induced osteoporosis",
    author = "Farahmand, P. and Marin, F. and Hawkins, F. and Moericke, R. and Ringe, and J. D. and Glueer, C. -C. and Papaioannou, N. and Minisola, S. and and Martinez, G. and Nolla, J. M. and Niedhart, C. and Guanabens, N. and and Nuti, R. and Martin-Mola, E. and Thomasius, F. and Pena, J. and Graeff, and C. and Kapetanos, G. and Petto, H. and Gentzel, A. and Reisinger, A. and and Zysset, P. K.",
    journal = "Osteoporosis International",
    year = "2013",
    volume = "24",
    number = "12",
    pages = "2971-2981",
    publisher = "Springer-Verlag London Ltd",
    issn = "0937-941X, 1433-2965",
    doi = "10.1007/s00198-013-2379-5",
    keywords = "Biochemical markers of bone turnover; bone strength; finite element
analysis; glucocorticoid-induced osteoporosis; male osteoporosis;
teriparatide",
    abstract = "Changes of the bone formation marker PINP correlated positively with
improvements in vertebral strength in men with glucocorticoid-induced
osteoporosis (GIO) who received 18-month treatment with teriparatide,
but not with risedronate. These results support the use of PINP as a
surrogate marker of bone strength in GIO patients treated with
teriparatide.
Introduction To investigate the correlations between biochemical markers
of bone turnover and vertebral strength estimated by finite element
analysis (FEA) in men with GIO.
Methods A total of 92 men with GIO were included in an 18-month,
randomized, open-label trial of teriparatide (20 mu g/day, n=45) and
risedronate (35 mg/week, n=47). High-resolution quantitative computed
tomography images of the 12th thoracic vertebra obtained at baseline, 6
and 18 months were converted into digital nonlinear FE models and
subjected to anterior bending, axial compression and torsion. Stiffness
and strength were computed for each model and loading mode. Serum
biochemical markers of bone formation (amino-terminal-propeptide of type
I collagen [PINP]) and bone resorption (type I collagen cross-linked
C-telopeptide degradation fragments [CTx]) were measured at baseline,
3 months, 6 months and 18 months. A mixed-model of repeated measures
analysed changes from baseline and between-group differences. Spearman
correlations assessed the relationship between changes from baseline of
bone markers with FEA variables.
Results PINP and CTx levels increased in the teriparatide group and
decreased in the risedronate group. FEA-derived parameters increased in
both groups, but were significantly higher at 18 months in the
teriparatide group. Significant positive correlations were found between
changes from baseline of PINP at 3, 6 and 18 months with changes in FE
strength in the teriparatide-treated group, but not in the risedronate
group.
Conclusions Positive correlations between changes in a biochemical
marker of bone formation and improvement of biomechanical properties
support the use of PINP as a surrogate marker of bone strength in
teriparatide-treated GIO patients."
}