Effect of monthly ibandronate on hip structural geometry in men with low bone density

Summary Hip structural analysis (HSA) performed in a subset of participants from the STudy Researching Osteoporosis iN Guys (STRONG) demonstrated that 1 year of ibandronate treatment was associated with a significant improvement in some but not all parameters of hip geometry relative to placebo in men with low bone density. Introduction HSA was performed on dual-energy X-ray absorptiometry (DXA) images in a subset of participants from the STRONG to examine the impact of monthly ibandronate on geometric properties of the hip in men with low bone density. Methods This prespecified subgroup analysis evaluated men in the intent-to-treat population of STRONG with baseline and 12-month DXA data. Cross-sectional geometric parameters of the femoral shaft (FS), intertrochanter region (IT), and narrow neck (NN) were calculated from femoral DXA scans. All analyses were exploratory. Treatment differences were evaluated using analysis of covariance, which adjusted for baseline parameter value, testosterone level, and treatment. Results HSA was performed on DXA scans from 89 men (34 placebo; 55 monthly ibandronate). Significant increases in average cortical thickness and cross-sectional area and decreases (i.e., improvements) in the buckling ratio were observed at the FS and IT at 12 months for ibandronatetreated men compared with placebo-treated men. No significant differences were observed between ibandronate and placebo for any NN HSA parameters. Conclusions One year of ibandronate treatment was associated with a significant improvement in some but not all parameters of hip geometry relative to placebo in men with low bone density, suggesting that ibandronate may improve resistance to axial compressive forces and bending forces at the hip.