Table 3.
Bone Mineral Density and Fracture Risk With Aromatase Inhibitors and Tamoxifen
| Trial | Endpoint | AI vs Comparator | P Value | |
|---|---|---|---|---|
| Anastrozole vs Tamoxifen | ||||
| ATAC[26-28] | Lumbar spine BMD, 24 mo Fracture, 40 mo Fracture, 60 mo | −4.0% | 1.9% | .003 |
| 7.1% | 4.4% | <.0001 | ||
| 11.0% | 7.7% | <.05 | ||
| Letrozole vs Placebo | ||||
| MA17[29–31] | Total hip BMD, 24 mo Osteoporosis, 30 mo | −3.6% | −0.71% | .044 |
| 8.0% | 6.0% | .003 | ||
| Letrozole vs Tamoxifen | ||||
| BIG1-98[32] | Fracture, 24 mo | 5.7% | 4.0% | .0006 |
| Anastrozole vs Tamoxifen | ||||
| ABCSG-8/ARNO-95[33] | Fracture, 28 mo | 2.4% | 1.2% | .015 |
| Anastrozole vs Tamoxifena | ||||
| ABCSG-12[[33] | Lumbar spine BMD, 36 mo | −17.4% | 11.6% | <.0001 |
| Exemestane vs Tamoxifen | ||||
| IES[34,35] | Lumbar spine BMD, 12 mo Total hip BMD, 12 mo Fracture, 31 mo | −3.17% | −.19% | <.0001 |
| −2.15% | −.58% | .001 | ||
| 3.1% | 2.3% | .05 | ||
| Exemestane vs Placebo | ||||
| Lonning et al [36,37] | Femoral neck BMD, 24 mob | −2.72% | −1.48% | .023 |
a
Both plus the GnRH agonist goserelin.
b
Annual rate calculated after 2 years.
AI = aromatase inhibitor; BMD = bone mineral density.