Table 3.
Change in DXA and QCT measures over 36 months in response to zoledronic acid (5 mg) or placebo
| Variable | Zoledronic acid (95% CI) | Placebo (95% CI) | Between-treatment difference (95% CI) | p value |
|---|---|---|---|---|
| Spine | (n=67) | (n=68) | ||
| Lumbar spine BMD (DXA) | 8.81 (7.31, 10.31) | 1.83 (0.34, 3.32) | 6.98 (4.86, 9.10) | <0.0001 |
| Spine BMD (QCT) | (n=92) | (n=88) | ||
| AP view DXA-like | 5.98 (4.51, 7.45) | 0.31 (−1.20, 1.81) | 5.67 (3.56, 7.77) | <0.0001. |
| Lateral view DXA-like | 9.80 (7.40, 12.20) | 1.44 (−1.01, 3.90) | 8.36 (4.93, 11.78) | <0.0001 |
| Total bone trabeculara | 0.006381 (0.003515, 0.009247) | 0.000627 (−0.002304, 0.003558) | 0.005754 (0.001654, 0.009853) | 0.0062. |
| Hip | (n=97) | (n=86) | ||
| Femoral neck BMD (DXA) | 4.03 (2.85, 5.22) | −1.06 (−2.32, 0.20) | 5.10 (3.36, 6.83) | <0.0001 |
| Trochanter BMD (DXA) | 5.84 (4.67, 7.02) | −1.62 (−2.86, −0.37) | 7.46 (5.74, 9.17) | <0.0001 |
| Total hip BMD (DXA) | 3.53 (2.62, 4.44) | −1.54 (−2.50, −0.57) | 5.07 (3.74, 6.39) | <0.0001 |
| Femoral neck BMD (QCT) | (n=93) | (n=86) | ||
| Integral | 0.92 (−0.39, 2.22) | −3.10 (−4.46, −1.74) | 4.02 (2.13, 5.90) | <0.0001. |
| Trabeculara | −0.00576 (−0.00946, −0.00206) | −0.00559 (−0.00944, −0.00174) | −0.000168 (−0.0055, 0.00517) | 0.951 |
| Cortical | −0.86 (−1.94, 0.21) | −1.81 (−2.92, −0.69) | 0.94 (−0.61, 2.50) | 0.2323 |
| Trochanter BMD (QCT) | (n=93) | (n=86) | ||
| Integral | 3.27 (2.00, 4.54) | −3.26 (−4.58, −1.94) | 6.53 (4.70, 8.36) | <0.0001. |
| Trabecular | 2.98 (−0.08, 6.04) | −7.76 (−10.94, −4.57) | 10.74 (6.32, 15.20) | <0.0001. |
| Cortical | −0.54 (−1.26, 0.18) | −1.46 (−2.21, −0.71) | 0.92 (−1.22, 1.96) | 0.0834. |
| Total hip BMD (QCT) | (n=93) | (n=86) | ||
| Integral | 2.86 (1.65, 4.07) | −3.15 (−4.41, −1.90) | 6.02 (4.27, 7.76) | <0.0001 |
| Trabecular | 2.04 (−1.30, 5.38) | −8.73 (−12.20, −5.26) | 10.77 (5.95, 15.59) | <0.0001. |
| Cortical | −0.43 (−1.14, 0.27) | −1.43 (−2.16, −0.70) | 1.00 (−0.02, 2.02) | 0.0541 |
| Cortical volume measurements(QCT) | (n=93) | (n=86) | ||
| Femoral neck cortical bone volume | 3.31 (0.62, 6.00) | 1.11 (−1.69, 3.91) | 2.20 (−1.68, 6.09) | 0.2640. |
| Trochanter cortical bone volume | 8.83 (5.70, 11.95) | 0.13 (−3.12, 3.37) | 8.70 (4.20, 13.20) | 0.0002 |
| Total hip cortical bone volume | 7.20 (4.53, 9.86) | −0.02 (−2.79, 2.79) | 7.22 (3.38, 11.06) | 0.0003 |
| Strength indices(QCT) | (n=93) | (n=86) | ||
| MNCS | 2.44 (0.68, 4.19) | 2.75 (0.92, 4.57) | −3.10 (−2.84, 2.22) | 0.8097 |
| MXCS | 2.65 (1.53, 3.78) | 1.83 (0.66, 3.00) | 0.82 (−0.80, 2.44) | 0.3188 |
| Femoral neck BSI | −2.25 (−3.42, −1.08) | −2.21 (−3.43, −1.00) | −0.03 (−1.72, 1.65) | 0.9674 |
| Femoral neck CSI | 4.91 (2.06, 7.76) | −3.70 (−6.67, −0.74) | 8.61 (4.50, 12.72) | 0.0001 |
| Trochanter CSI | 9.83 (7.12, 12.55) | −4.25 (−7.08, −1.43) | 14.08 (10.16, 18.00) | <0.0001 |
Data are presented as mean (95% CI) percentage change, with p values showing the differences between the two groups
a
Since baseline values are very low, data are shown as absolute rather than relative changes
n number of patients with baseline and follow up DXA or QCT data for a specific measurement and timepoint
BSI bending/torsion strength index
CSI compression strength index