Ibandronate increases sclerostin levels and bone strength in male patients with idiopathic osteoporosis.
The pathomechanism of male idiopathic osteoporosis (MIO) differs from postmenopausal osteoporosis with regard to alterations in osteoblast activity. We evaluated intravenous ibandronate (IBN) in 25 MIO patients with fragility fractures in a prospective, monocentric, single-arm, and open-label study for 24 months. The impact and changes of sclerostin (Scl), Dickkopf-1 (DKK-1), CTX, and PINP were examined. Additionally, volumetric cortical, trabecular and areal bone mineral density (BMD), trabecular bone score (TBS), and finite element analyses (FEA) were evaluated. Compared to baseline, median Scl levels were increased after 1 month (Δ 121%, p < 0.0001) and remained elevated for 12 months. DKK-1 decreased (p < 0.001) to a lesser extent until month 9 with values comparable to baseline at study endpoint. Early changes (baseline-month 1) of Scl negatively correlated with early changes of DKK-1 (-0.72), CTX (-0.82), and PINP (-0.55; p < 0.005 for all). The overall changes over the 24 months study period of Scl negatively correlated with decreased CTX (-0.32) and DKK-1 levels (-0.57, p < 0.0001 for both); CTX and PINP changes positively correlated at each time point (p < 0.001). Volumetric hip BMD increased by 12 and 18%, respectively (p < 0.0001 for both). Cross-sectional moment of inertia and section modulus for total hip significantly improved (p < 0.05 for all). Areal BMD at total hip, spine, and TBS increased. FEA displayed an increase in bone strength both in the hip (17%) and vertebrae (13%, all p < 0.0001) at anatomical sites susceptible for fragility fracture. IBN increases Scl and improves cortical and trabecular bone strength with early and ongoing vigorous suppression of bone resorption.
Medical Department II, St. Vincent Hospital, Academic Teaching Hospital of the Medical University of Vienna, Stumpergasse 13, 1060, Vienna, Austria, christian.muschitz@bhs.at.
Christian
C
Muschitz
Roland
R
Kocijan
Dieter
D
Pahr
Janina M
JM
Patsch
Karin
K
Amrein
Barbara M
BM
Misof
Alexandra
A
Kaider
Heinrich
H
Resch
Peter
P
Pietschmann
D048868:Adaptor Proteins, Signal Transducing; D000328:Adult; D015519:Bone Density / Q000187:drug effects*; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D019485:Bone Morphogenetic Proteins / Q000097:blood*; D016723:Bone Remodeling / Q000187:drug effects; D004164:Diphosphonates / Q000627:therapeutic use*; D004797:Enzyme-Linked Immunosorbent Assay; D020342:Finite Element Analysis; D005819:Genetic Markers; D006801:Humans; D000077557:Ibandronic Acid; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000097:blood / Q000188:drug therapy*
D048868:Adaptor Proteins, Signal Transducing; D050071:Bone Density Conservation Agents; D019485:Bone Morphogenetic Proteins; D004164:Diphosphonates; D005819:Genetic Markers; C422903:SOST protein, human; D000077557:Ibandronic Acid